Yi-June Huang - Academia.edu (original) (raw)

Papers by Yi-June Huang

Research paper thumbnail of Polypyrrole-coated copper@graphene core-shell nanoparticles for supercapacitor application

Nanotechnology

The performance of supercapacitors strongly depends on the electrochemical characterizations of e... more The performance of supercapacitors strongly depends on the electrochemical characterizations of electrode materials. Herein, a composite material consisted of polypyrrole (PPy) and multilayer graphene-wrapped copper nanoparticles (PPy/MLG-Cu NPs) is fabricated on a flexible carbon cloth (CC) substrate via two-step synthesis process for supercapacitor application. Where, MLG-Cu NPs are prepared on CC by one-step chemical vapor deposition synthesis approach; thereafter, the PPy is further deposited on the MLG-Cu NPs/CC via electropolymerization. The related material characterizations of PPy/MLG-Cu NPs are well investigated by scanning electron microscopic, high resolution transmission electron microscopy, Raman spectrometer and x-ray photoelectron spectroscopy; the electrochemical behaviors of the pertinent electrodes are studied by cyclic voltammogram, galvanostatic charge/discharge and electrochemical impedance spectroscopy measurements. The flexible electrode with PPy/MLG-Cu NPs co...

Research paper thumbnail of Nanoflower-like P-doped Nickel Oxide as a Catalytic Counter Electrode for Dye-Sensitized Solar Cells

Nanomaterials

Flower-like phosphorus-doped nickel oxide (P-NiO) is proposed as a counter electrode (CE) for dye... more Flower-like phosphorus-doped nickel oxide (P-NiO) is proposed as a counter electrode (CE) for dye-sensitized solar cells (DSSCs). The flower-like nickel oxide essentially serves as the matrix for the CE, which is expected to promote a two-dimensional electron transport pathway. The phosphorus is intended to improve the catalytic ability by creating more active sites in the NiO for the catalysis of triiodide ions (I3−) to iodide ions (I−) on the surface of the CE. The P-NiO is controlled by a sequencing of precursor concentration, which allows the P-NiO to possess different features. The debris aggregation occurs in the P-NiO-1, while the P-NiO-0.75 leads to the incomplete flower-like nanosheets. The complete flower-like morphology can be observed in the P-NiO-0.5, P-NiO-0.25 and P-NiO-0.1 catalytic electrodes. The DSSC with the P-NiO-0.5 CE achieves a power conversion efficiency (η) of 9.05%, which is better than that of the DSSC using a Pt CE (η = 8.51%); it also performs better th...

Research paper thumbnail of Hierarchical pompon-like cobalt phosphide as a platinum-free electrocatalyst for dye-sensitized solar cells

Journal of Materials Chemistry C

Hierarchical 3D CoP micro-pompon assembled by 1D-nano-needle-array decorated 2D-micro-sheets prov... more Hierarchical 3D CoP micro-pompon assembled by 1D-nano-needle-array decorated 2D-micro-sheets provided facile charge transfer and lots of electrocatalytic active sites to deliver decent DSSC performance (8.80% at 1 sun; 17.27% at 7 klux).

Research paper thumbnail of Free-standing vertically aligned tin disulfide nanosheets for ultrasensitive aptasensor design toward Alzheimer’s diagnosis applications

Chemical Engineering Journal

Research paper thumbnail of Hierarchical Nanoneedle –decorated Shell Structure Of Cobalt Phosphide As Counter Electrode For Dye-sensitized Solar Cell

Research paper thumbnail of Carbon-Based Nanocomposite Materials for High-Performance Supercapacitors

Novel Nanomaterials, 2021

Lightweight, flexible, wearable, and portable electronic gadgets have drawn significant attention... more Lightweight, flexible, wearable, and portable electronic gadgets have drawn significant attention in modern electronics industry. To power these gadgets, great efforts have been made to develop highly efficient energy-storage equipment. Among various power sources, a supercapacitor, acting as a bridge between the conventional battery and electrolytic capacitor, has been considered a promising portable energy storage device because of its high power density, fast charge/discharge rate, adequate operational safety, and excellent working lifetime. Hybrid supercapacitors, which combine redox materials with carbon-based materials, exhibit tremendous potential to fulfill the requirement of practical applications. In this chapter, we will review recent reports focusing on composite materials (i.e. metal oxide, metal hydroxide, and metal dichalcogenide composited with carbon materials) for the application in supercapacitors. The conclusion and futuristic prospects and challenges of highly e...

Research paper thumbnail of Clinically oriented Alzheimer's biosensors: expanding the horizons towards point-of-care diagnostics and beyond

RSC Advances, 2021

Advancements of clinically driven biosensors in current Alzheimer's diagnosis are highlighted... more Advancements of clinically driven biosensors in current Alzheimer's diagnosis are highlighted in both in vitro and in vivo applications.

Research paper thumbnail of Recent Advances on Pt-Free Electro-Catalysts for Dye-Sensitized Solar Cells

Molecules, 2021

Since Prof. Grätzel and co-workers achieved breakthrough progress on dye-sensitized solar cells (... more Since Prof. Grätzel and co-workers achieved breakthrough progress on dye-sensitized solar cells (DSSCs) in 1991, DSSCs have been extensively investigated and wildly developed as a potential renewable power source in the last two decades due to their low cost, low energy-intensive processing, and high roll-to-roll compatibility. During this period, the highest efficiency recorded for DSSC under ideal solar light (AM 1.5G, 100 mW cm−2) has increased from ~7% to ~14.3%. For the practical use of solar cells, the performance of photovoltaic devices in several conditions with weak light irradiation (e.g., indoor) or various light incident angles are also an important item. Accordingly, DSSCs exhibit high competitiveness in solar cell markets because their performances are less affected by the light intensity and are less sensitive to the light incident angle. However, the most used catalyst in the counter electrode (CE) of a typical DSSC is platinum (Pt), which is an expensive noble metal...

Research paper thumbnail of Nanostructured Transition Metal Compounds as Highly Efficient Electrocatalysts for Dye-Sensitized Solar Cells

Solar Cells [Working Title], 2020

Nowadays, the requirement of energy increases every year, however, the major energy resource is f... more Nowadays, the requirement of energy increases every year, however, the major energy resource is fossil fuel, a limiting source. Dye-sensitized solar cells (DSSCs) are a promising renewable energy source, which could be the major power supply for the future. Recently, the transition metal component has been demonstrated as potential material for counter electrode of platinum (Pt)-free DSSCs owing to their excellent electrocatalytic ability and their abundance on earth. Furthermore, the transition metal components exist different special nanostructures, which provide high surface area and various electron transport routs during electrocatalytic reaction. In this chapter, transition metal components with different nanostructures used for the application of electrocatalyst in DSSCs will be introduced; the performance of electrocatalyst between intrinsic heterogeneous rate constant and effective electrocatalytic surface area are also be clarified. Final, the advantages of the electrocata...

Research paper thumbnail of N- and S-codoped graphene hollow nanoballs as an efficient Pt-free electrocatalyst for dye-sensitized solar cells

Journal of Power Sources, 2019

� N,S-codoped graphene hollow nanoballs (N,S-GHBs) are investigated for DSSCs. � Highly curved GH... more � N,S-codoped graphene hollow nanoballs (N,S-GHBs) are investigated for DSSCs. � Highly curved GHBs provide high surface areas and sufficient active sites. � N,S-GHBs enhance electrocatalytic activity toward the triiodide reduction reaction.

Research paper thumbnail of Hierarchical urchin-like CoSe2/CoSeO3 electro-catalysts for dye-sensitized solar cells: up to 19% PCE under dim light illumination

Journal of Materials Chemistry A, 2019

A hierarchical urchin-like structure of CoSe2/CoSeO3 (denoted as CoSe2/CoSeO3-UL) is synthesized ... more A hierarchical urchin-like structure of CoSe2/CoSeO3 (denoted as CoSe2/CoSeO3-UL) is synthesized by a one-step hydrothermal method and investigated as the electro-catalyst for the counter electrode (CE) of dye-sensitized solar cells (DSSCs).

Research paper thumbnail of A Pt-free pristine monolithic carbon aerogel counter electrode for dye-sensitized solar cells: up to 20% under dim light illumination

Nanoscale, 2019

The best carbon aerogel CE gives an η of 9.08% at 100 mW cm−2 and 20.1% at 2.18 mW cm−2.

Research paper thumbnail of Microemulsion-controlled synthesis of CoSe 2 /CoSeO 3 composite crystals for electrocatalysis in dye-sensitized solar cells

Materials Today Energy, 2017

Cobalt diselenide/cobalt selenite (CoSe 2 /CoSeO 3) composite crystals with nanocube (NC), nanoro... more Cobalt diselenide/cobalt selenite (CoSe 2 /CoSeO 3) composite crystals with nanocube (NC), nanorod (NR), and nanoparticle (NP) structures were obtained through a microemulsion-assisted hydrothermal synthesis by incorporating the anionic surfactant docusate sodium salt (AOT), the cationic surfactant cetyltrimethyl ammonium bromide (CTAB), and the non-ionic surfactant Triton ® X-100, respectively. The as-prepared CoSe 2 /CoSeO 3 crystals were utilized as the electrocatalysts in dye-sensitized solar cells (DSSCs). Among all the crystals, the one obtained through Triton ® X-100 enables its DSSC to achieve the best power conversion efficiency (h) of 9.27%, which is even better than that of the DSSC with platinum (Pt) (7.91%). The catalytic abilities of the counter electrodes were analyzed by cyclic voltammetry (CV), Tafel polarization plots, and electrochemical impedance spectra (EIS). The photovoltaic behaviors are substantiated by incident photon-to-electron conversion efficiency (IPCE) spectra. The DSSC with CoSe 2 / CoSeO 3-NP exhibited an h of 9.27% at 100 mW cm À2 , a better h of 9.31% at 50 mW cm À2 , and the best h of 9.41% at 10 mW cm À2 , thereby extending the scope of application of this DSSC from outdoor to indoor regions. The earth abundant, low-cost material of CoSe 2 /CoSeO 3-NP can be a promising electrocatalytic material to replace the expensive Pt in a DSSC.

Research paper thumbnail of One-step synthesis of graphene hollow nanoballs with various nitrogen-doped states for electrocatalysis in dye-sensitized solar cells

Materials Today Energy, 2018

Nitrogen-doped graphene hollow nanoballs (N-GHBs) were synthesized in chemical vapor deposition (... more Nitrogen-doped graphene hollow nanoballs (N-GHBs) were synthesized in chemical vapor deposition (CVD) reaction using melamine as a chemical precursor via an in situ nitrogen-doping approach. In the CVD reaction, N-GHBs were deposited directly on carbon cloth (CC) to be used as an efficient metal-free electrocatalyst for dye-sensitized solar cell (DSSC) applications. The highly curved N-GHBs could avoid the self-assembly restacking of planar graphene sheets, which usually occurred during the film preparation. Keeping oxygen contaminations from N-GHBs, the characteristic electrical conductivity of graphene was preserved in the as-synthesized N-GHBs. By controlling the evaporation temperature of melamine, the nitrogen-doping content of 8.7e14.0% and different nitrogen-doped configurations in N-GHBs could be adjusted. The catalytic activities of different nitrogen-doped states in N-GHBs toward the triiodide (I 3 À) reduction in DSSCs were investigated, revealing that the pyridinic and quaternary nitrogens, rather than the total nitrogen doping level, in N-GHBs are mainly responsible for their catalytic activities in DSSCs. For solar cell applications, the high surface area and heteroatomic nitrogens of GHBs can remarkably improve the catalytic activity toward the triiodide reduction, lower the charge-transfer resistance, and enhance the corresponding photovoltaic performance (7.53%), which is comparable to that (7.70%) of a standard sputtered Pt counter electrode-based cell. These exceptional properties allow N-GHBs/CC to act as a promising electrocatalytic electrode for DSSC and other electrochemical energy applications.

Research paper thumbnail of Electrospun membranes of imidazole-grafted PVDF-HFP polymeric ionic liquids for highly efficient quasi-solid-state dye-sensitized solar cells

Journal of Materials Chemistry A, 2018

The PFII membranes have three functions that render the DSSC with η of 9.26% and long-term stabil... more The PFII membranes have three functions that render the DSSC with η of 9.26% and long-term stability over 1500 h (up to 97% of its initial η).

Research paper thumbnail of Phase-Engineered Weyl Semi-Metallic Mox W1-x Te2 Nanosheets as a Highly Efficient Electrocatalyst for Dye-Sensitized Solar Cells

Solar RRL, 2019

The emerging Weyl semi-metals with robust topological surface states are very promising candidate... more The emerging Weyl semi-metals with robust topological surface states are very promising candidates to rationally develop new-generation electrocatalysts for dye-sensitized solar cells (DSSCs). In this study, a chemical vapor deposition (CVD) method to synthesize highly crystalline Weyl semi-metallic Mo x W 1-x Te 2 nanocrystals, which are applied for the counter electrode (CE) of DSSCs for the first time, are employed. By controlling the temperaturedependent phase-engineered synthesis, the nanocrystal grown at 760-C exhibits the mixed phases of semiconducting T d-& 2H-Mo 0.32 W 0.67 Te 2.01 with charge carrier density of (1.20 AE 0.02) Â 10 19 cm À3 ; whereas, the nanocrystal synthesized at 820 C shows a single phase of semi-metallic T d-Mo 0.29 W 0.72 Te 1.99 with much higher carrier density of (1.59 AE 0.04) Â 10 20 cm À3. In the cyclic voltammetry (CV) analysis over 200 cycles, the Mo x W 1x Te 2-based electrodes show better stability in the I À /I 3 À electrolyte than a Pt electrode. In DSSC tests, a T d-Mo 0.29 W 0.72 Te 1.99-decorated CE achieves the efficiency (η) of 8.85%, better than those CEs fabricated with T d-& 2H-Mo 0.32 W 0.67 Te 2.01 (7.81%) and sputtered Pt (8.01%). The electrochemical impedance spectra reveal that the T d-Mo 0.29 W 0.72 Te 1.99 electrode possesses low charge-transfer resistance in electrocatalytic reactions. These exceptional properties make Weyl semi-metallic T d-Mo x W 1-x Te 2 a potential electrode material for a wide variety of electrocatalytic applications.

Research paper thumbnail of A zeolitic imidazolate framework-derived ZnSe/N-doped carbon cube hybrid electrocatalyst as the counter electrode for dye-sensitized solar cells

Journal of Materials Chemistry A, 2018

A ZIF-ZnSe-NC composite derived from ZIF-7 was synthesized and used as the electrocatalyst for th... more A ZIF-ZnSe-NC composite derived from ZIF-7 was synthesized and used as the electrocatalyst for the counter electrode (CE) in dye-sensitized solar cells, which performed better than that using a Pt CE.

Research paper thumbnail of ZnO double layer film with a novel organic sensitizer as an efficient photoelectrode for dye–sensitized solar cells

Journal of Power Sources, 2016

The CR147 dyeesensitized ZnO film is almost free from Zn 2þ /dye eagglomerations. The DSSC with C... more The CR147 dyeesensitized ZnO film is almost free from Zn 2þ /dye eagglomerations. The DSSC with CR147 dyeesensitized ZnO double layer film shows a high h of 6.89%. A ZnO DSSC with CR147 dye has 40% higher h than that of the cell with N719 dye. EIS is used to study the charge transfer kinetics of DSSCs with CR147 dye. The aterest stability of DSSCs with CR147esensitized ZnO double layer is studied.

Research paper thumbnail of Hierarchical TiO1.1Se0.9-wrapped carbon cloth as the TCO-free and Pt-free counter electrode for iodide-based and cobalt-based dye-sensitized solar cells

Journal of Materials Chemistry A, 2017

Hierarchical, flexible, and platinum-free TiO1.1Se0.9/carbon cloth counter electrode efficiently ... more Hierarchical, flexible, and platinum-free TiO1.1Se0.9/carbon cloth counter electrode efficiently rendered its dye-sensitized solar cell 9.47% and 10.32% efficiencies in iodide-based and cobalt-based electrolytes, respectively.

Research paper thumbnail of Metal-organic framework/sulfonated polythiophene on carbon cloth as a flexible counter electrode for dye-sensitized solar cells

Nano Energy, 2017

Metal-organic framework (MOF-525) is firstly introduced as the electro-catalyst for the counter e... more Metal-organic framework (MOF-525) is firstly introduced as the electro-catalyst for the counter electrode (CE) of a dye-sensitized solar cell (DSSC). When MOF-525 was mixed with the conductive binder of sulfonated-poly(thiophene-3-[2-(2-methoxyethoxy)-ethoxy]-2,5-diyl) (s-PT), a composite film of MOF-525/s-PT was successfully deposited on a flexible substrate, carbon cloth (CC). The one-dimensional carbon fibers in CC were intended to provide oriented electron transfer pathways as a conductive core, and the composite film of MOF-525/s-PT covered on each carbon fiber in CC was designed to trigger the reduction of I 3 − as an electro-catalytic shell. Thus, a hierarchical electron transfer network was established. In the MOF-525 nanoparticle, its nodes (zirconium oxide) and linkers (meso-tetra(4carboxyphenyl)porphyrin) were both verified to function as the electro-catalytic active sites for I 3 − reduction. The best MOF-525/s-PT composite counter electrode rendered 8.91±0.02% to its DSSC, showing the promising potential to replace traditional platinum (8.21±0.02%). At dim light condition (10 mW cm-2), the best cell with MOF-525/s-PT composite CE shows a great cell efficiency (η) of 9.75%, which is higher than that of the cell measured at 100 mW cm-2 .

Research paper thumbnail of Polypyrrole-coated copper@graphene core-shell nanoparticles for supercapacitor application

Nanotechnology

The performance of supercapacitors strongly depends on the electrochemical characterizations of e... more The performance of supercapacitors strongly depends on the electrochemical characterizations of electrode materials. Herein, a composite material consisted of polypyrrole (PPy) and multilayer graphene-wrapped copper nanoparticles (PPy/MLG-Cu NPs) is fabricated on a flexible carbon cloth (CC) substrate via two-step synthesis process for supercapacitor application. Where, MLG-Cu NPs are prepared on CC by one-step chemical vapor deposition synthesis approach; thereafter, the PPy is further deposited on the MLG-Cu NPs/CC via electropolymerization. The related material characterizations of PPy/MLG-Cu NPs are well investigated by scanning electron microscopic, high resolution transmission electron microscopy, Raman spectrometer and x-ray photoelectron spectroscopy; the electrochemical behaviors of the pertinent electrodes are studied by cyclic voltammogram, galvanostatic charge/discharge and electrochemical impedance spectroscopy measurements. The flexible electrode with PPy/MLG-Cu NPs co...

Research paper thumbnail of Nanoflower-like P-doped Nickel Oxide as a Catalytic Counter Electrode for Dye-Sensitized Solar Cells

Nanomaterials

Flower-like phosphorus-doped nickel oxide (P-NiO) is proposed as a counter electrode (CE) for dye... more Flower-like phosphorus-doped nickel oxide (P-NiO) is proposed as a counter electrode (CE) for dye-sensitized solar cells (DSSCs). The flower-like nickel oxide essentially serves as the matrix for the CE, which is expected to promote a two-dimensional electron transport pathway. The phosphorus is intended to improve the catalytic ability by creating more active sites in the NiO for the catalysis of triiodide ions (I3−) to iodide ions (I−) on the surface of the CE. The P-NiO is controlled by a sequencing of precursor concentration, which allows the P-NiO to possess different features. The debris aggregation occurs in the P-NiO-1, while the P-NiO-0.75 leads to the incomplete flower-like nanosheets. The complete flower-like morphology can be observed in the P-NiO-0.5, P-NiO-0.25 and P-NiO-0.1 catalytic electrodes. The DSSC with the P-NiO-0.5 CE achieves a power conversion efficiency (η) of 9.05%, which is better than that of the DSSC using a Pt CE (η = 8.51%); it also performs better th...

Research paper thumbnail of Hierarchical pompon-like cobalt phosphide as a platinum-free electrocatalyst for dye-sensitized solar cells

Journal of Materials Chemistry C

Hierarchical 3D CoP micro-pompon assembled by 1D-nano-needle-array decorated 2D-micro-sheets prov... more Hierarchical 3D CoP micro-pompon assembled by 1D-nano-needle-array decorated 2D-micro-sheets provided facile charge transfer and lots of electrocatalytic active sites to deliver decent DSSC performance (8.80% at 1 sun; 17.27% at 7 klux).

Research paper thumbnail of Free-standing vertically aligned tin disulfide nanosheets for ultrasensitive aptasensor design toward Alzheimer’s diagnosis applications

Chemical Engineering Journal

Research paper thumbnail of Hierarchical Nanoneedle –decorated Shell Structure Of Cobalt Phosphide As Counter Electrode For Dye-sensitized Solar Cell

Research paper thumbnail of Carbon-Based Nanocomposite Materials for High-Performance Supercapacitors

Novel Nanomaterials, 2021

Lightweight, flexible, wearable, and portable electronic gadgets have drawn significant attention... more Lightweight, flexible, wearable, and portable electronic gadgets have drawn significant attention in modern electronics industry. To power these gadgets, great efforts have been made to develop highly efficient energy-storage equipment. Among various power sources, a supercapacitor, acting as a bridge between the conventional battery and electrolytic capacitor, has been considered a promising portable energy storage device because of its high power density, fast charge/discharge rate, adequate operational safety, and excellent working lifetime. Hybrid supercapacitors, which combine redox materials with carbon-based materials, exhibit tremendous potential to fulfill the requirement of practical applications. In this chapter, we will review recent reports focusing on composite materials (i.e. metal oxide, metal hydroxide, and metal dichalcogenide composited with carbon materials) for the application in supercapacitors. The conclusion and futuristic prospects and challenges of highly e...

Research paper thumbnail of Clinically oriented Alzheimer's biosensors: expanding the horizons towards point-of-care diagnostics and beyond

RSC Advances, 2021

Advancements of clinically driven biosensors in current Alzheimer's diagnosis are highlighted... more Advancements of clinically driven biosensors in current Alzheimer's diagnosis are highlighted in both in vitro and in vivo applications.

Research paper thumbnail of Recent Advances on Pt-Free Electro-Catalysts for Dye-Sensitized Solar Cells

Molecules, 2021

Since Prof. Grätzel and co-workers achieved breakthrough progress on dye-sensitized solar cells (... more Since Prof. Grätzel and co-workers achieved breakthrough progress on dye-sensitized solar cells (DSSCs) in 1991, DSSCs have been extensively investigated and wildly developed as a potential renewable power source in the last two decades due to their low cost, low energy-intensive processing, and high roll-to-roll compatibility. During this period, the highest efficiency recorded for DSSC under ideal solar light (AM 1.5G, 100 mW cm−2) has increased from ~7% to ~14.3%. For the practical use of solar cells, the performance of photovoltaic devices in several conditions with weak light irradiation (e.g., indoor) or various light incident angles are also an important item. Accordingly, DSSCs exhibit high competitiveness in solar cell markets because their performances are less affected by the light intensity and are less sensitive to the light incident angle. However, the most used catalyst in the counter electrode (CE) of a typical DSSC is platinum (Pt), which is an expensive noble metal...

Research paper thumbnail of Nanostructured Transition Metal Compounds as Highly Efficient Electrocatalysts for Dye-Sensitized Solar Cells

Solar Cells [Working Title], 2020

Nowadays, the requirement of energy increases every year, however, the major energy resource is f... more Nowadays, the requirement of energy increases every year, however, the major energy resource is fossil fuel, a limiting source. Dye-sensitized solar cells (DSSCs) are a promising renewable energy source, which could be the major power supply for the future. Recently, the transition metal component has been demonstrated as potential material for counter electrode of platinum (Pt)-free DSSCs owing to their excellent electrocatalytic ability and their abundance on earth. Furthermore, the transition metal components exist different special nanostructures, which provide high surface area and various electron transport routs during electrocatalytic reaction. In this chapter, transition metal components with different nanostructures used for the application of electrocatalyst in DSSCs will be introduced; the performance of electrocatalyst between intrinsic heterogeneous rate constant and effective electrocatalytic surface area are also be clarified. Final, the advantages of the electrocata...

Research paper thumbnail of N- and S-codoped graphene hollow nanoballs as an efficient Pt-free electrocatalyst for dye-sensitized solar cells

Journal of Power Sources, 2019

� N,S-codoped graphene hollow nanoballs (N,S-GHBs) are investigated for DSSCs. � Highly curved GH... more � N,S-codoped graphene hollow nanoballs (N,S-GHBs) are investigated for DSSCs. � Highly curved GHBs provide high surface areas and sufficient active sites. � N,S-GHBs enhance electrocatalytic activity toward the triiodide reduction reaction.

Research paper thumbnail of Hierarchical urchin-like CoSe2/CoSeO3 electro-catalysts for dye-sensitized solar cells: up to 19% PCE under dim light illumination

Journal of Materials Chemistry A, 2019

A hierarchical urchin-like structure of CoSe2/CoSeO3 (denoted as CoSe2/CoSeO3-UL) is synthesized ... more A hierarchical urchin-like structure of CoSe2/CoSeO3 (denoted as CoSe2/CoSeO3-UL) is synthesized by a one-step hydrothermal method and investigated as the electro-catalyst for the counter electrode (CE) of dye-sensitized solar cells (DSSCs).

Research paper thumbnail of A Pt-free pristine monolithic carbon aerogel counter electrode for dye-sensitized solar cells: up to 20% under dim light illumination

Nanoscale, 2019

The best carbon aerogel CE gives an η of 9.08% at 100 mW cm−2 and 20.1% at 2.18 mW cm−2.

Research paper thumbnail of Microemulsion-controlled synthesis of CoSe 2 /CoSeO 3 composite crystals for electrocatalysis in dye-sensitized solar cells

Materials Today Energy, 2017

Cobalt diselenide/cobalt selenite (CoSe 2 /CoSeO 3) composite crystals with nanocube (NC), nanoro... more Cobalt diselenide/cobalt selenite (CoSe 2 /CoSeO 3) composite crystals with nanocube (NC), nanorod (NR), and nanoparticle (NP) structures were obtained through a microemulsion-assisted hydrothermal synthesis by incorporating the anionic surfactant docusate sodium salt (AOT), the cationic surfactant cetyltrimethyl ammonium bromide (CTAB), and the non-ionic surfactant Triton ® X-100, respectively. The as-prepared CoSe 2 /CoSeO 3 crystals were utilized as the electrocatalysts in dye-sensitized solar cells (DSSCs). Among all the crystals, the one obtained through Triton ® X-100 enables its DSSC to achieve the best power conversion efficiency (h) of 9.27%, which is even better than that of the DSSC with platinum (Pt) (7.91%). The catalytic abilities of the counter electrodes were analyzed by cyclic voltammetry (CV), Tafel polarization plots, and electrochemical impedance spectra (EIS). The photovoltaic behaviors are substantiated by incident photon-to-electron conversion efficiency (IPCE) spectra. The DSSC with CoSe 2 / CoSeO 3-NP exhibited an h of 9.27% at 100 mW cm À2 , a better h of 9.31% at 50 mW cm À2 , and the best h of 9.41% at 10 mW cm À2 , thereby extending the scope of application of this DSSC from outdoor to indoor regions. The earth abundant, low-cost material of CoSe 2 /CoSeO 3-NP can be a promising electrocatalytic material to replace the expensive Pt in a DSSC.

Research paper thumbnail of One-step synthesis of graphene hollow nanoballs with various nitrogen-doped states for electrocatalysis in dye-sensitized solar cells

Materials Today Energy, 2018

Nitrogen-doped graphene hollow nanoballs (N-GHBs) were synthesized in chemical vapor deposition (... more Nitrogen-doped graphene hollow nanoballs (N-GHBs) were synthesized in chemical vapor deposition (CVD) reaction using melamine as a chemical precursor via an in situ nitrogen-doping approach. In the CVD reaction, N-GHBs were deposited directly on carbon cloth (CC) to be used as an efficient metal-free electrocatalyst for dye-sensitized solar cell (DSSC) applications. The highly curved N-GHBs could avoid the self-assembly restacking of planar graphene sheets, which usually occurred during the film preparation. Keeping oxygen contaminations from N-GHBs, the characteristic electrical conductivity of graphene was preserved in the as-synthesized N-GHBs. By controlling the evaporation temperature of melamine, the nitrogen-doping content of 8.7e14.0% and different nitrogen-doped configurations in N-GHBs could be adjusted. The catalytic activities of different nitrogen-doped states in N-GHBs toward the triiodide (I 3 À) reduction in DSSCs were investigated, revealing that the pyridinic and quaternary nitrogens, rather than the total nitrogen doping level, in N-GHBs are mainly responsible for their catalytic activities in DSSCs. For solar cell applications, the high surface area and heteroatomic nitrogens of GHBs can remarkably improve the catalytic activity toward the triiodide reduction, lower the charge-transfer resistance, and enhance the corresponding photovoltaic performance (7.53%), which is comparable to that (7.70%) of a standard sputtered Pt counter electrode-based cell. These exceptional properties allow N-GHBs/CC to act as a promising electrocatalytic electrode for DSSC and other electrochemical energy applications.

Research paper thumbnail of Electrospun membranes of imidazole-grafted PVDF-HFP polymeric ionic liquids for highly efficient quasi-solid-state dye-sensitized solar cells

Journal of Materials Chemistry A, 2018

The PFII membranes have three functions that render the DSSC with η of 9.26% and long-term stabil... more The PFII membranes have three functions that render the DSSC with η of 9.26% and long-term stability over 1500 h (up to 97% of its initial η).

Research paper thumbnail of Phase-Engineered Weyl Semi-Metallic Mox W1-x Te2 Nanosheets as a Highly Efficient Electrocatalyst for Dye-Sensitized Solar Cells

Solar RRL, 2019

The emerging Weyl semi-metals with robust topological surface states are very promising candidate... more The emerging Weyl semi-metals with robust topological surface states are very promising candidates to rationally develop new-generation electrocatalysts for dye-sensitized solar cells (DSSCs). In this study, a chemical vapor deposition (CVD) method to synthesize highly crystalline Weyl semi-metallic Mo x W 1-x Te 2 nanocrystals, which are applied for the counter electrode (CE) of DSSCs for the first time, are employed. By controlling the temperaturedependent phase-engineered synthesis, the nanocrystal grown at 760-C exhibits the mixed phases of semiconducting T d-& 2H-Mo 0.32 W 0.67 Te 2.01 with charge carrier density of (1.20 AE 0.02) Â 10 19 cm À3 ; whereas, the nanocrystal synthesized at 820 C shows a single phase of semi-metallic T d-Mo 0.29 W 0.72 Te 1.99 with much higher carrier density of (1.59 AE 0.04) Â 10 20 cm À3. In the cyclic voltammetry (CV) analysis over 200 cycles, the Mo x W 1x Te 2-based electrodes show better stability in the I À /I 3 À electrolyte than a Pt electrode. In DSSC tests, a T d-Mo 0.29 W 0.72 Te 1.99-decorated CE achieves the efficiency (η) of 8.85%, better than those CEs fabricated with T d-& 2H-Mo 0.32 W 0.67 Te 2.01 (7.81%) and sputtered Pt (8.01%). The electrochemical impedance spectra reveal that the T d-Mo 0.29 W 0.72 Te 1.99 electrode possesses low charge-transfer resistance in electrocatalytic reactions. These exceptional properties make Weyl semi-metallic T d-Mo x W 1-x Te 2 a potential electrode material for a wide variety of electrocatalytic applications.

Research paper thumbnail of A zeolitic imidazolate framework-derived ZnSe/N-doped carbon cube hybrid electrocatalyst as the counter electrode for dye-sensitized solar cells

Journal of Materials Chemistry A, 2018

A ZIF-ZnSe-NC composite derived from ZIF-7 was synthesized and used as the electrocatalyst for th... more A ZIF-ZnSe-NC composite derived from ZIF-7 was synthesized and used as the electrocatalyst for the counter electrode (CE) in dye-sensitized solar cells, which performed better than that using a Pt CE.

Research paper thumbnail of ZnO double layer film with a novel organic sensitizer as an efficient photoelectrode for dye–sensitized solar cells

Journal of Power Sources, 2016

The CR147 dyeesensitized ZnO film is almost free from Zn 2þ /dye eagglomerations. The DSSC with C... more The CR147 dyeesensitized ZnO film is almost free from Zn 2þ /dye eagglomerations. The DSSC with CR147 dyeesensitized ZnO double layer film shows a high h of 6.89%. A ZnO DSSC with CR147 dye has 40% higher h than that of the cell with N719 dye. EIS is used to study the charge transfer kinetics of DSSCs with CR147 dye. The aterest stability of DSSCs with CR147esensitized ZnO double layer is studied.

Research paper thumbnail of Hierarchical TiO1.1Se0.9-wrapped carbon cloth as the TCO-free and Pt-free counter electrode for iodide-based and cobalt-based dye-sensitized solar cells

Journal of Materials Chemistry A, 2017

Hierarchical, flexible, and platinum-free TiO1.1Se0.9/carbon cloth counter electrode efficiently ... more Hierarchical, flexible, and platinum-free TiO1.1Se0.9/carbon cloth counter electrode efficiently rendered its dye-sensitized solar cell 9.47% and 10.32% efficiencies in iodide-based and cobalt-based electrolytes, respectively.

Research paper thumbnail of Metal-organic framework/sulfonated polythiophene on carbon cloth as a flexible counter electrode for dye-sensitized solar cells

Nano Energy, 2017

Metal-organic framework (MOF-525) is firstly introduced as the electro-catalyst for the counter e... more Metal-organic framework (MOF-525) is firstly introduced as the electro-catalyst for the counter electrode (CE) of a dye-sensitized solar cell (DSSC). When MOF-525 was mixed with the conductive binder of sulfonated-poly(thiophene-3-[2-(2-methoxyethoxy)-ethoxy]-2,5-diyl) (s-PT), a composite film of MOF-525/s-PT was successfully deposited on a flexible substrate, carbon cloth (CC). The one-dimensional carbon fibers in CC were intended to provide oriented electron transfer pathways as a conductive core, and the composite film of MOF-525/s-PT covered on each carbon fiber in CC was designed to trigger the reduction of I 3 − as an electro-catalytic shell. Thus, a hierarchical electron transfer network was established. In the MOF-525 nanoparticle, its nodes (zirconium oxide) and linkers (meso-tetra(4carboxyphenyl)porphyrin) were both verified to function as the electro-catalytic active sites for I 3 − reduction. The best MOF-525/s-PT composite counter electrode rendered 8.91±0.02% to its DSSC, showing the promising potential to replace traditional platinum (8.21±0.02%). At dim light condition (10 mW cm-2), the best cell with MOF-525/s-PT composite CE shows a great cell efficiency (η) of 9.75%, which is higher than that of the cell measured at 100 mW cm-2 .