Zhiping Lai - Academia.edu (original) (raw)

Papers by Zhiping Lai

Research paper thumbnail of Peierls-type metal-insulator transition in carbon nanostructures

Carbon, 2021

We report the observation of Peierls-type metal-insulator transition in carbon nanostructures for... more We report the observation of Peierls-type metal-insulator transition in carbon nanostructures formed by chemical vapor deposition inside the pore network of the ZSM-5 zeolite. The Raman spectrum of this nanocarbon@ZSM-5 indicates a clear signature of the radial breathing mode (RBM) for (3,0) carbon nanotubes that can constitute the carbon network segments. Electrical transport measurements on multiple few-micron-sized nanocarbon@ZSM-5 crystals showed metallic temperature of resistance dependence down to 30 K, at which point the resistance exhibited a sharp upturn that is accompanied by the opening of a quasigap at the Fermi level as indicated by the differential resistance measurements. Further Hall measurements have yielded both the sign of the charge carrier and its density. The latter demonstrated excellent consistency with the quasigap data. We employed first-principles calculations to verify that there can indeed be softening of the phonon modes in the (3,0) carbon nanotubes.

Research paper thumbnail of Metal–organic-framework derived Co–Pd bond is preferred over Fe–Pd for reductive upgrading of furfural to tetrahydrofurfuryl alcohol

Dalton Transactions, 2019

The metal–organic-framework-derived Co–Pd bond can more efficiently catalyze the reductive upgrad... more The metal–organic-framework-derived Co–Pd bond can more efficiently catalyze the reductive upgrading of furfural to tetrahydrofurfuryl alcohol production as compared to the Fe–Pd bond.

Research paper thumbnail of Dual-Function Conductive Copper Hollow Fibers for Microfiltration and Anti-biofouling in Electrochemical Membrane Bioreactors

Frontiers in Chemistry, 2018

Membrane bioreactors (MBRs) with polymeric/ceramic microfiltration (MF) membranes have been commo... more Membrane bioreactors (MBRs) with polymeric/ceramic microfiltration (MF) membranes have been commonly used for wastewater treatment today. However, membrane biofouling often results in a dramatically-reduced service life of MF membranes, which limits the application of this technology. In this study, Cu hollow fiber membranes (Cu-HFMs) with low resistivity (104.8-309.8 n •m) and anti-biofouling properties were successfully synthesized. Further analysis demonstrated that Cu-HFMs reduced at 625 • C achieved the bimodal pore size distribution of ∼1 µm and a porosity of 46%, which enable high N 2 permeance (1.56 × 10 −5 mol/m 2 s pa) and pure water flux (5812 LMH/bar). The Cu-HFMs were further applied as the conductive cathodes, as well as MF membranes, in the electrochemical membrane bioreactor (EMBR) system that was enriched with domestic wastewater at an applied voltage of 0.9 V. Excellent permeate quality (Total suspended solids (TSS) = 11 mg/L) was achieved at a flux of 9.47 LMH after Cu-HFM filtration, with relatively stable transmembrane pressure (TMP) and low Cu 2+ dissolvability (<25 µg/L). The anti-biofouling over time was demonstrated by SEM characterization of the rare biofilm formation on the Cu-HFM cathode surface. By using Cu-HFMs in EMBR systems, an effective strategy to control the membrane biofouling is developed in this study.

Research paper thumbnail of Synthesis of zeolite/carbon nanotube composite for gas separation

Canadian Journal of Chemistry, 2017

A hybrid composite of NaY zeolite and amine modified multi-walled carbon nanotube (MWCNT) has bee... more A hybrid composite of NaY zeolite and amine modified multi-walled carbon nanotube (MWCNT) has been synthesized by hydrothermal method. The obtained NaY/CNT composite (NC composite) was characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), and BET analysis. CO2, CH4 and N2 adsorption at two different temperatures and P < 5 bar on the composite was investigated by the volumetric method. The selectivity of the NC composite for CO2/CH4 and CO2/N2 has been studied and compared with pure NaY zeolite. Crystal structures of NC composite were similar to those of pure NaY zeolite, but the surface area and pore volume of the NC composite are enhanced. Incorporation of MWCNTs into NaY zeolite increases nucleation sites for the formation of NaY zeolite crystals, resulting in the smaller size of NaY zeolite crystals. Gas adsorption capacity and selectivity of NC composite increased because of enhancement of micropore volume. The result...

Research paper thumbnail of Attainability and minimum energy of multiple-stage cascade membrane systems

Journal of Membrane Science, 2015

Process design and simulation of multi-stage membrane systems have been widely studied in many ga... more Process design and simulation of multi-stage membrane systems have been widely studied in many gas separation systems. However, general guidelines have not been developed yet for the attainability and the minimum energy consumption of a multi-stage membrane system. Such information is important for conceptual process design and thus it is the topic of this work. Using a well-mixed membrane model, it was determined that the attainability curve of multi-stage systems is defined by the pressure ratio and membrane selectivity. Using the constant recycle ratio scheme, the recycle ratio can shift the attainability behavior between single-stage and multistage membrane systems. When the recycle ratio is zero, all of the multi-stage membrane processes will decay to a single-stage membrane process. When the recycle ratio approaches infinity, the required selectivity and pressure ratio reach their absolute minimum values, which have a simple relationship with that of a single-stage membrane process, as follows: ܵ = ඥܵ ଵ , ߛ = √ ߛ ଵ , where n is the number of stages. The minimum energy consumption of a multi-stage membrane process is primarily determined by the membrane selectivity and recycle ratio. A low recycle ratio can significantly reduce the required membrane selectivity without substantial energy penalty. The energy envelope curve can provide a guideline from an energy perspective to determine the minimum required membrane selectivity in membrane process designs to compete with conventional separation processes, such as distillation.

Research paper thumbnail of Fixed-Bed Adsorption Separation Of Xylene Isomers over SiO2/Silicallite-1 Core-Shell Adsorbents

Chemical Engineering Research Bulletin, 2013

SiO 2 /Silicalite-1 core-shell material has been demonstrated as potential shape selective adsorb... more SiO 2 /Silicalite-1 core-shell material has been demonstrated as potential shape selective adsorbent in gas phase separation of p-xylene from a mixture of p/o-xylene isomers. The core-shell composite comprised of large silica core and thin polycrystalline silicalite-1 shell which was synthesized via a self-assembly of silicalite-1 nanocrystals on core silica surface followed by a secondary seeded growth method. The core materials, SiO 2 used in this study has mesoporosity with an average pore diameter of 60Å and hence offers no shape selectivity for xylene isomers. However, the shell, silicalite-1 contains rigid pore structures and preferentially adsorbs p-xylene from their isomers mixtures. A series of adsorption fixed bed breakthrough adsorption/desorption experiment was performed to obtain the equilibrium isotherms and adsorption isotherm parameters of xylene isomers. The equilibrium isotherms of xylene isomers follow the Langmuir's model. A chromatographic adsorption model has been used to describe the fixed-bed breakthrough profiles of xylene isomers. The model has successfully predicted the responses of the binary mixtures of p/o-xylene isomers. The SiO 2 /silicalite-1 core-shell adsorbents have shown para-selectivity as high as 15.

Research paper thumbnail of Correction: Fluorido-bridged robust metal–organic frameworks for efficient C2H2/CO2 separation under moist conditions

Chemical Science

Correction for ‘Fluorido-bridged robust metal–organic frameworks for efficient C2H2/CO2 separatio... more Correction for ‘Fluorido-bridged robust metal–organic frameworks for efficient C2H2/CO2 separation under moist conditions’ by Yi-Ming Gu et al., Chem. Sci., 2023, https://doi.org/10.1039/d2sc06699h.

Research paper thumbnail of Fluorido-bridged robust metal–organic frameworks for efficient C2H2/CO2 separation under moist conditions

Chemical Science

A new nano MOF with high-coordinated bridged and terminal fluorine species exhibits efficient C2H... more A new nano MOF with high-coordinated bridged and terminal fluorine species exhibits efficient C2H2/CO2 separation under moist conditions.

Research paper thumbnail of Radiative cooling for energy sustainability: Materials, systems, and applications

Physical Review Materials

As a sustainable technology, radiative cooling has received considerable attention due to its pot... more As a sustainable technology, radiative cooling has received considerable attention due to its potential in energy sustainability. Unlike conventional cooling techniques, radiative cooling does not consume electricity during its operation and is therefore particularly attractive in reducing the energy demand for cooling and addressing global warming by reducing carbon emissions. The general principle requires a radiative cooler to be thermally emissive to dissipate heat via thermal radiation. During the daytime, the cooler needs to minimize the solar heating effect to ensure subambient temperatures. Guided by these criteria, researchers have developed various materials with engineered optical, thermal, and mechanical features. In this review, we will first explore the fundamentals of heat transfer in radiative cooling processes. Subsequently, we will summarize the state-of-the-art progress on material synthesis and system designs. Building upon those recently developed features, we will review how this technology has been implemented in practical applications, ranging from thermal management of buildings, semiconductor cooling, personal comfort design, and atmospheric water harvesting. Finally, we will conclude this review by identifying and discussing some of the remaining challenges requiring future research and development.

Research paper thumbnail of Electropolymerization growth of an ultrathin, compact, conductive and microporous (UCCM) polycarbazole membrane for high energy Li–S batteries

Nano Energy, 2020

Indium tin oxide (ITO) slide were purchased from Sigma. TBAPF6 was recrystallized twice in ethano... more Indium tin oxide (ITO) slide were purchased from Sigma. TBAPF6 was recrystallized twice in ethanol and vacuum dried for 24 h before use. Dichloromethane was purified by distillation with CaH2 as the water removal agent. The single-wall carbon nanotube (CNT) was purchased from

Research paper thumbnail of Protection of Lithium Anode by a Highly Porous PVDF Membrane for High-Performance Li–S Battery

ACS Applied Energy Materials, 2020

The Li-S battery is considered as the next-generation energy storage solution largely because of ... more The Li-S battery is considered as the next-generation energy storage solution largely because of its high energy density. However, the lithium metal anode has suffered from the "shuttle effect" of soluble polysulfide species and the formation of dendrites that cause quick performance decay and safety issues. Here, a polyvinylidene fluoride (PVDF) membrane that contains a hierarchical porous structure was introduced as a protection layer to insulate the lithium anode from polysulfide shuttling and dendrite formation. The PVDF protected Li-S battery showed a capacity of around 850 mAh g-1 and Coulombic efficiency of 98% over 200 cycles at 0.5 C. Both performances are significantly improved from the normal Li-S batteries. The PVDF membrane is stable, easy to coat, and scalable, which offers a convenient, affordable, yet effective strategy for achieving commercialization of high energy density and safe Li-S batteries.

Research paper thumbnail of Design and Mechanistic Study of Highly Durable Carbon-Coated Cobalt Diphosphide Core–Shell Nanostructure Electrocatalysts for the Efficient and Stable Oxygen Evolution Reaction

ACS Applied Materials & Interfaces, 2019

Facile synthesis of hierarchically functional, catalytically active, and electrochemically stable... more Facile synthesis of hierarchically functional, catalytically active, and electrochemically stable nanostructures holds tremendous promise for catalyzing efficient and durable oxygen evolution reaction (OER), yet remains a formidable challenge. Herein, we report the scalable production of core-shell nanostructures comprised of carbon-coated cobalt diphosphide nanosheets, C@CoP 2, via three simple steps: (i) electrochemical deposition of Co-species; (ii) gas phase phosphidation, and (iii) carbonization of CoP 2 for catalytic durability enhancement. Electrochemical characterizations showed that C@CoP 2 delivers an overpotential of 234 mV, retains its initial activity for over 80 hours of continuous operation, and exhibits a fast OER rate of 63.8 mV dec-1 in base.

Research paper thumbnail of Facile Single-Step Fabrication of Robust Superhydrophobic Carbon Nanotube Films on Different Porous Supports

Industrial & Engineering Chemistry Research, 2019

Research paper thumbnail of Fabrication of Self-Entangled 3D Carbon Nanotube Networks from Metal–Organic Frameworks for Li-Ion Batteries

ACS Applied Nano Materials, 2018

introducing ethyne. In addition, the highly conductive 3D porous CNT network facilitates electron... more introducing ethyne. In addition, the highly conductive 3D porous CNT network facilitates electron transfer and provides an excellent platform for high-performance Li-ion batteries (LIB).

Research paper thumbnail of Single‐Site Ruthenium Pincer Complex Knitted into Porous Organic Polymers for Dehydrogenation of Formic Acid

ChemSusChem, 2018

Owing to its capacity for reversible hydrogen storage, formic acid (FA) holds great promise as an... more Owing to its capacity for reversible hydrogen storage, formic acid (FA) holds great promise as an energy carrier alternative to conventional fossil fuels systems. While the decomposition of FA to hydrogen (H2) and carbon dioxide (CO2) through homogeneous catalysis has been well-established, the selective and efficient dehydrogenation of FA by a robust heterogeneous catalyst remains a challenge. Herein, a novel heterogeneous ruthenium-pincer framework with single-atomic sites was prepared in one step by the direct knitting of a phosphorous-nitrogen PN 3 P-pincer ruthenium complex in a porous organic polymer. The heterogeneous ruthenium complex efficiently dehydrogenates formic acid in both organic and aqueous media with remarkably enhanced stability. Notably, no detectible CO was generated and a turnover number of 145,300 was attained in a continuous experiment with no significant decline in catalytic reactivity (in sharp contrast, total TON of only 5,600 was obtained with the homogeneous analog under the same conditions). The single-atomic sites in the porous framework allowed the combination of the desirable attributes of high reactivity and selectivity of a homogeneous catalyst with the significantly enhanced catalyst stability and reusability benefits of heterogeneous catalysis.

Research paper thumbnail of Spatially isolated palladium in porous organic polymers by direct knitting for versatile organic transformations

Journal of Catalysis, 2017

et al. (2017) Spatially isolated palladium in porous organic polymers by direct knitting for vers... more et al. (2017) Spatially isolated palladium in porous organic polymers by direct knitting for versatile organic transformations.

Research paper thumbnail of Diverse catalytic reactivity of a dearomatized PN3P*–nickel hydride pincer complex towards CO2 reduction

Chemical Communications, 2018

A dearomatized PN3P*–nickel hydride complex catalyzes hydrosilylation of CO2.

Research paper thumbnail of Synthesis of Sub-10 nm Two-Dimensional Covalent Organic Thin Film with Sharp Molecular Sieving Nanofiltration

ACS applied materials & interfaces, Jan 6, 2018

We demonstrated here a novel and facile synthesis of two-dimensional (2D) covalent organic thin f... more We demonstrated here a novel and facile synthesis of two-dimensional (2D) covalent organic thin film with pore size around 1.5 nm using a planar, amphiphilic and substituted heptacyclic truxene based triamine and a simple dialdehyde as building blocks by dynamic imine bond formation at the air/water interface using Langmuir-Blodgett (LB) method. Optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and atomic force microscopy (AFM), all unanimously showed the formation of large, molecularly thin and free-standing membrane that can be easily transferred on different substrate surfaces. The 2D membrane supported on a porous polysulfone showed a rejection rate of 64 and 71% for NaCl and MgSO, respectively, and a clear molecular sieving at molecular size around 1.3 nm, which demonstrated a great potential in the application of pretreatment of seawater desalination and separation of organic molecules.

Research paper thumbnail of Functional Two-Dimensional Coordination Polymeric Layer as a Charge Barrier in Li-S Batteries

ACS nano, Jan 4, 2018

Ultra-thin two dimensional (2D) polymeric layers are capable of separating gases and molecules ba... more Ultra-thin two dimensional (2D) polymeric layers are capable of separating gases and molecules based on the reported size exclusion mechanism. What is equally important but missing today is to explore the 2D layers with the charge functionality which enable applications using charge exclusion principle. This work demonstrates a simple and scalable method of synthesizing a free-standing 2D coordination polymer Zn2(Benzimidazolate)2(OH)2 at the air/water interfaces. The hydroxyl (-OH) groups are stoichiometrically coordinated and implement electrostatic charges in the 2D structures, providing powerful functionality as a charge barrier. Electrochemical performance of the Li-S battery shows that the Zn2(Benzimidazolate)2(OH)2 coordination polymer layers efficiently mitigate the polysulfide shuttling effects and largely enhance the battery capacity and cycle performance. The synthesis of the proposed coordination polymeric layers is simple, scalable, cost saving and promising for practic...

Research paper thumbnail of Renewable aromatics from the degradation of polystyrene under mild conditions

Journal of Saudi Chemical Society, 2017

The dissertation of Nouf AlJabri is approved by the examination committee.

Research paper thumbnail of Peierls-type metal-insulator transition in carbon nanostructures

Carbon, 2021

We report the observation of Peierls-type metal-insulator transition in carbon nanostructures for... more We report the observation of Peierls-type metal-insulator transition in carbon nanostructures formed by chemical vapor deposition inside the pore network of the ZSM-5 zeolite. The Raman spectrum of this nanocarbon@ZSM-5 indicates a clear signature of the radial breathing mode (RBM) for (3,0) carbon nanotubes that can constitute the carbon network segments. Electrical transport measurements on multiple few-micron-sized nanocarbon@ZSM-5 crystals showed metallic temperature of resistance dependence down to 30 K, at which point the resistance exhibited a sharp upturn that is accompanied by the opening of a quasigap at the Fermi level as indicated by the differential resistance measurements. Further Hall measurements have yielded both the sign of the charge carrier and its density. The latter demonstrated excellent consistency with the quasigap data. We employed first-principles calculations to verify that there can indeed be softening of the phonon modes in the (3,0) carbon nanotubes.

Research paper thumbnail of Metal–organic-framework derived Co–Pd bond is preferred over Fe–Pd for reductive upgrading of furfural to tetrahydrofurfuryl alcohol

Dalton Transactions, 2019

The metal–organic-framework-derived Co–Pd bond can more efficiently catalyze the reductive upgrad... more The metal–organic-framework-derived Co–Pd bond can more efficiently catalyze the reductive upgrading of furfural to tetrahydrofurfuryl alcohol production as compared to the Fe–Pd bond.

Research paper thumbnail of Dual-Function Conductive Copper Hollow Fibers for Microfiltration and Anti-biofouling in Electrochemical Membrane Bioreactors

Frontiers in Chemistry, 2018

Membrane bioreactors (MBRs) with polymeric/ceramic microfiltration (MF) membranes have been commo... more Membrane bioreactors (MBRs) with polymeric/ceramic microfiltration (MF) membranes have been commonly used for wastewater treatment today. However, membrane biofouling often results in a dramatically-reduced service life of MF membranes, which limits the application of this technology. In this study, Cu hollow fiber membranes (Cu-HFMs) with low resistivity (104.8-309.8 n •m) and anti-biofouling properties were successfully synthesized. Further analysis demonstrated that Cu-HFMs reduced at 625 • C achieved the bimodal pore size distribution of ∼1 µm and a porosity of 46%, which enable high N 2 permeance (1.56 × 10 −5 mol/m 2 s pa) and pure water flux (5812 LMH/bar). The Cu-HFMs were further applied as the conductive cathodes, as well as MF membranes, in the electrochemical membrane bioreactor (EMBR) system that was enriched with domestic wastewater at an applied voltage of 0.9 V. Excellent permeate quality (Total suspended solids (TSS) = 11 mg/L) was achieved at a flux of 9.47 LMH after Cu-HFM filtration, with relatively stable transmembrane pressure (TMP) and low Cu 2+ dissolvability (<25 µg/L). The anti-biofouling over time was demonstrated by SEM characterization of the rare biofilm formation on the Cu-HFM cathode surface. By using Cu-HFMs in EMBR systems, an effective strategy to control the membrane biofouling is developed in this study.

Research paper thumbnail of Synthesis of zeolite/carbon nanotube composite for gas separation

Canadian Journal of Chemistry, 2017

A hybrid composite of NaY zeolite and amine modified multi-walled carbon nanotube (MWCNT) has bee... more A hybrid composite of NaY zeolite and amine modified multi-walled carbon nanotube (MWCNT) has been synthesized by hydrothermal method. The obtained NaY/CNT composite (NC composite) was characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), and BET analysis. CO2, CH4 and N2 adsorption at two different temperatures and P < 5 bar on the composite was investigated by the volumetric method. The selectivity of the NC composite for CO2/CH4 and CO2/N2 has been studied and compared with pure NaY zeolite. Crystal structures of NC composite were similar to those of pure NaY zeolite, but the surface area and pore volume of the NC composite are enhanced. Incorporation of MWCNTs into NaY zeolite increases nucleation sites for the formation of NaY zeolite crystals, resulting in the smaller size of NaY zeolite crystals. Gas adsorption capacity and selectivity of NC composite increased because of enhancement of micropore volume. The result...

Research paper thumbnail of Attainability and minimum energy of multiple-stage cascade membrane systems

Journal of Membrane Science, 2015

Process design and simulation of multi-stage membrane systems have been widely studied in many ga... more Process design and simulation of multi-stage membrane systems have been widely studied in many gas separation systems. However, general guidelines have not been developed yet for the attainability and the minimum energy consumption of a multi-stage membrane system. Such information is important for conceptual process design and thus it is the topic of this work. Using a well-mixed membrane model, it was determined that the attainability curve of multi-stage systems is defined by the pressure ratio and membrane selectivity. Using the constant recycle ratio scheme, the recycle ratio can shift the attainability behavior between single-stage and multistage membrane systems. When the recycle ratio is zero, all of the multi-stage membrane processes will decay to a single-stage membrane process. When the recycle ratio approaches infinity, the required selectivity and pressure ratio reach their absolute minimum values, which have a simple relationship with that of a single-stage membrane process, as follows: ܵ = ඥܵ ଵ , ߛ = √ ߛ ଵ , where n is the number of stages. The minimum energy consumption of a multi-stage membrane process is primarily determined by the membrane selectivity and recycle ratio. A low recycle ratio can significantly reduce the required membrane selectivity without substantial energy penalty. The energy envelope curve can provide a guideline from an energy perspective to determine the minimum required membrane selectivity in membrane process designs to compete with conventional separation processes, such as distillation.

Research paper thumbnail of Fixed-Bed Adsorption Separation Of Xylene Isomers over SiO2/Silicallite-1 Core-Shell Adsorbents

Chemical Engineering Research Bulletin, 2013

SiO 2 /Silicalite-1 core-shell material has been demonstrated as potential shape selective adsorb... more SiO 2 /Silicalite-1 core-shell material has been demonstrated as potential shape selective adsorbent in gas phase separation of p-xylene from a mixture of p/o-xylene isomers. The core-shell composite comprised of large silica core and thin polycrystalline silicalite-1 shell which was synthesized via a self-assembly of silicalite-1 nanocrystals on core silica surface followed by a secondary seeded growth method. The core materials, SiO 2 used in this study has mesoporosity with an average pore diameter of 60Å and hence offers no shape selectivity for xylene isomers. However, the shell, silicalite-1 contains rigid pore structures and preferentially adsorbs p-xylene from their isomers mixtures. A series of adsorption fixed bed breakthrough adsorption/desorption experiment was performed to obtain the equilibrium isotherms and adsorption isotherm parameters of xylene isomers. The equilibrium isotherms of xylene isomers follow the Langmuir's model. A chromatographic adsorption model has been used to describe the fixed-bed breakthrough profiles of xylene isomers. The model has successfully predicted the responses of the binary mixtures of p/o-xylene isomers. The SiO 2 /silicalite-1 core-shell adsorbents have shown para-selectivity as high as 15.

Research paper thumbnail of Correction: Fluorido-bridged robust metal–organic frameworks for efficient C2H2/CO2 separation under moist conditions

Chemical Science

Correction for ‘Fluorido-bridged robust metal–organic frameworks for efficient C2H2/CO2 separatio... more Correction for ‘Fluorido-bridged robust metal–organic frameworks for efficient C2H2/CO2 separation under moist conditions’ by Yi-Ming Gu et al., Chem. Sci., 2023, https://doi.org/10.1039/d2sc06699h.

Research paper thumbnail of Fluorido-bridged robust metal–organic frameworks for efficient C2H2/CO2 separation under moist conditions

Chemical Science

A new nano MOF with high-coordinated bridged and terminal fluorine species exhibits efficient C2H... more A new nano MOF with high-coordinated bridged and terminal fluorine species exhibits efficient C2H2/CO2 separation under moist conditions.

Research paper thumbnail of Radiative cooling for energy sustainability: Materials, systems, and applications

Physical Review Materials

As a sustainable technology, radiative cooling has received considerable attention due to its pot... more As a sustainable technology, radiative cooling has received considerable attention due to its potential in energy sustainability. Unlike conventional cooling techniques, radiative cooling does not consume electricity during its operation and is therefore particularly attractive in reducing the energy demand for cooling and addressing global warming by reducing carbon emissions. The general principle requires a radiative cooler to be thermally emissive to dissipate heat via thermal radiation. During the daytime, the cooler needs to minimize the solar heating effect to ensure subambient temperatures. Guided by these criteria, researchers have developed various materials with engineered optical, thermal, and mechanical features. In this review, we will first explore the fundamentals of heat transfer in radiative cooling processes. Subsequently, we will summarize the state-of-the-art progress on material synthesis and system designs. Building upon those recently developed features, we will review how this technology has been implemented in practical applications, ranging from thermal management of buildings, semiconductor cooling, personal comfort design, and atmospheric water harvesting. Finally, we will conclude this review by identifying and discussing some of the remaining challenges requiring future research and development.

Research paper thumbnail of Electropolymerization growth of an ultrathin, compact, conductive and microporous (UCCM) polycarbazole membrane for high energy Li–S batteries

Nano Energy, 2020

Indium tin oxide (ITO) slide were purchased from Sigma. TBAPF6 was recrystallized twice in ethano... more Indium tin oxide (ITO) slide were purchased from Sigma. TBAPF6 was recrystallized twice in ethanol and vacuum dried for 24 h before use. Dichloromethane was purified by distillation with CaH2 as the water removal agent. The single-wall carbon nanotube (CNT) was purchased from

Research paper thumbnail of Protection of Lithium Anode by a Highly Porous PVDF Membrane for High-Performance Li–S Battery

ACS Applied Energy Materials, 2020

The Li-S battery is considered as the next-generation energy storage solution largely because of ... more The Li-S battery is considered as the next-generation energy storage solution largely because of its high energy density. However, the lithium metal anode has suffered from the "shuttle effect" of soluble polysulfide species and the formation of dendrites that cause quick performance decay and safety issues. Here, a polyvinylidene fluoride (PVDF) membrane that contains a hierarchical porous structure was introduced as a protection layer to insulate the lithium anode from polysulfide shuttling and dendrite formation. The PVDF protected Li-S battery showed a capacity of around 850 mAh g-1 and Coulombic efficiency of 98% over 200 cycles at 0.5 C. Both performances are significantly improved from the normal Li-S batteries. The PVDF membrane is stable, easy to coat, and scalable, which offers a convenient, affordable, yet effective strategy for achieving commercialization of high energy density and safe Li-S batteries.

Research paper thumbnail of Design and Mechanistic Study of Highly Durable Carbon-Coated Cobalt Diphosphide Core–Shell Nanostructure Electrocatalysts for the Efficient and Stable Oxygen Evolution Reaction

ACS Applied Materials & Interfaces, 2019

Facile synthesis of hierarchically functional, catalytically active, and electrochemically stable... more Facile synthesis of hierarchically functional, catalytically active, and electrochemically stable nanostructures holds tremendous promise for catalyzing efficient and durable oxygen evolution reaction (OER), yet remains a formidable challenge. Herein, we report the scalable production of core-shell nanostructures comprised of carbon-coated cobalt diphosphide nanosheets, C@CoP 2, via three simple steps: (i) electrochemical deposition of Co-species; (ii) gas phase phosphidation, and (iii) carbonization of CoP 2 for catalytic durability enhancement. Electrochemical characterizations showed that C@CoP 2 delivers an overpotential of 234 mV, retains its initial activity for over 80 hours of continuous operation, and exhibits a fast OER rate of 63.8 mV dec-1 in base.

Research paper thumbnail of Facile Single-Step Fabrication of Robust Superhydrophobic Carbon Nanotube Films on Different Porous Supports

Industrial & Engineering Chemistry Research, 2019

Research paper thumbnail of Fabrication of Self-Entangled 3D Carbon Nanotube Networks from Metal–Organic Frameworks for Li-Ion Batteries

ACS Applied Nano Materials, 2018

introducing ethyne. In addition, the highly conductive 3D porous CNT network facilitates electron... more introducing ethyne. In addition, the highly conductive 3D porous CNT network facilitates electron transfer and provides an excellent platform for high-performance Li-ion batteries (LIB).

Research paper thumbnail of Single‐Site Ruthenium Pincer Complex Knitted into Porous Organic Polymers for Dehydrogenation of Formic Acid

ChemSusChem, 2018

Owing to its capacity for reversible hydrogen storage, formic acid (FA) holds great promise as an... more Owing to its capacity for reversible hydrogen storage, formic acid (FA) holds great promise as an energy carrier alternative to conventional fossil fuels systems. While the decomposition of FA to hydrogen (H2) and carbon dioxide (CO2) through homogeneous catalysis has been well-established, the selective and efficient dehydrogenation of FA by a robust heterogeneous catalyst remains a challenge. Herein, a novel heterogeneous ruthenium-pincer framework with single-atomic sites was prepared in one step by the direct knitting of a phosphorous-nitrogen PN 3 P-pincer ruthenium complex in a porous organic polymer. The heterogeneous ruthenium complex efficiently dehydrogenates formic acid in both organic and aqueous media with remarkably enhanced stability. Notably, no detectible CO was generated and a turnover number of 145,300 was attained in a continuous experiment with no significant decline in catalytic reactivity (in sharp contrast, total TON of only 5,600 was obtained with the homogeneous analog under the same conditions). The single-atomic sites in the porous framework allowed the combination of the desirable attributes of high reactivity and selectivity of a homogeneous catalyst with the significantly enhanced catalyst stability and reusability benefits of heterogeneous catalysis.

Research paper thumbnail of Spatially isolated palladium in porous organic polymers by direct knitting for versatile organic transformations

Journal of Catalysis, 2017

et al. (2017) Spatially isolated palladium in porous organic polymers by direct knitting for vers... more et al. (2017) Spatially isolated palladium in porous organic polymers by direct knitting for versatile organic transformations.

Research paper thumbnail of Diverse catalytic reactivity of a dearomatized PN3P*–nickel hydride pincer complex towards CO2 reduction

Chemical Communications, 2018

A dearomatized PN3P*–nickel hydride complex catalyzes hydrosilylation of CO2.

Research paper thumbnail of Synthesis of Sub-10 nm Two-Dimensional Covalent Organic Thin Film with Sharp Molecular Sieving Nanofiltration

ACS applied materials & interfaces, Jan 6, 2018

We demonstrated here a novel and facile synthesis of two-dimensional (2D) covalent organic thin f... more We demonstrated here a novel and facile synthesis of two-dimensional (2D) covalent organic thin film with pore size around 1.5 nm using a planar, amphiphilic and substituted heptacyclic truxene based triamine and a simple dialdehyde as building blocks by dynamic imine bond formation at the air/water interface using Langmuir-Blodgett (LB) method. Optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and atomic force microscopy (AFM), all unanimously showed the formation of large, molecularly thin and free-standing membrane that can be easily transferred on different substrate surfaces. The 2D membrane supported on a porous polysulfone showed a rejection rate of 64 and 71% for NaCl and MgSO, respectively, and a clear molecular sieving at molecular size around 1.3 nm, which demonstrated a great potential in the application of pretreatment of seawater desalination and separation of organic molecules.

Research paper thumbnail of Functional Two-Dimensional Coordination Polymeric Layer as a Charge Barrier in Li-S Batteries

ACS nano, Jan 4, 2018

Ultra-thin two dimensional (2D) polymeric layers are capable of separating gases and molecules ba... more Ultra-thin two dimensional (2D) polymeric layers are capable of separating gases and molecules based on the reported size exclusion mechanism. What is equally important but missing today is to explore the 2D layers with the charge functionality which enable applications using charge exclusion principle. This work demonstrates a simple and scalable method of synthesizing a free-standing 2D coordination polymer Zn2(Benzimidazolate)2(OH)2 at the air/water interfaces. The hydroxyl (-OH) groups are stoichiometrically coordinated and implement electrostatic charges in the 2D structures, providing powerful functionality as a charge barrier. Electrochemical performance of the Li-S battery shows that the Zn2(Benzimidazolate)2(OH)2 coordination polymer layers efficiently mitigate the polysulfide shuttling effects and largely enhance the battery capacity and cycle performance. The synthesis of the proposed coordination polymeric layers is simple, scalable, cost saving and promising for practic...

Research paper thumbnail of Renewable aromatics from the degradation of polystyrene under mild conditions

Journal of Saudi Chemical Society, 2017

The dissertation of Nouf AlJabri is approved by the examination committee.