Farid Harraz - Academia.edu (original) (raw)

Papers by Farid Harraz

Biosensors

In this study, a selective 4-nitrophenol (4-NP) sensor was developed onto a glassy carbon electro... more In this study, a selective 4-nitrophenol (4-NP) sensor was developed onto a glassy carbon electrode (GCE) as an electron-sensing substrate, which decorated with sol–gel, prepared Pt nanoparticles- (NPs) embedded polypyrole-carbon black (PPy-CB)/ZnO nanocomposites (NCs) using differential pulse voltammetry. Characterizations of the NCs were performed using Field Emission Scanning Electron Microscopy (FESEM), Energy-Dispersive Spectroscopy (EDS), X-ray Photoelectron Spectroscopy (XPS), Ultraviolet–visible Spectroscopy (UV–vis), Fourier Transform Infrared Spectroscopy (FTIR), High Resolution Transmission Electron Microscopy (HRTEM), and X-ray Diffraction Analysis (XRD). The GCE modified by conducting coating binders [poly(3,4-ethylenedioxythiophene) polystyrene sulfonate; PEDOT:PSS] based on Pt NPs/PPy-CB/ZnO NCs functioned as the working electrode and showed selectivity toward 4-NP in a phosphate buffer medium at pH 7.0. Our analysis of 4-NP showed the linearity from 1.5 to 40.5 µM, w...

Nanomaterials

Copper-silver and cobalt-silver alloy nanoparticles deposited on reduced graphene oxide (CuAg/rGO... more Copper-silver and cobalt-silver alloy nanoparticles deposited on reduced graphene oxide (CuAg/rGO and CoAg/rGO) were synthesized and examined as electrocatalysts for oxygen reduction reaction (ORR) and hydrogen peroxide reduction reaction (HPRR) in alkaline media. Characterization of the prepared samples was done by transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction analysis (XRD), and scanning electron microscopy with integrated energy-dispersive X-ray spectroscopy (SEM-EDS). CuAg/rGO and CoAg/rGO nanoparticles diameter ranged from 0.4 to 9.2 nm. The Ag loading was ca. 40 wt.% for both electrocatalysts, with that for Cu and Co being 35 and 17 wt.%, respectively. CoAg/rGO electrocatalyst showed a Tafel slope of 109 mV dec−1, significantly lower than that for CuAg/rGO (184 mV dec−1), suggesting faster ORR kinetics. Additionally, a higher diffusion current density was obtained for CoAg/rGO (−2.63 mA cm−2) than ...

Nanomaterials

Platinum–dysprosium (Pt–Dy) alloys prepared by the arc melting technique are assessed as potentia... more Platinum–dysprosium (Pt–Dy) alloys prepared by the arc melting technique are assessed as potential electrodes for the oxygen reduction reaction (ORR) using voltammetry and chronoamperometry in alkaline media. A relatively small change (10 at.%) in the alloy composition brought a notable difference in the alloys’ performance for the ORR. Pt40Dy60 electrode, i.e., the electrode with a lower amount of Pt, was identified to have a higher activity towards ORR as evidenced by lower overpotential and higher current densities under identical experimental conditions. Furthermore, DFT calculations point out the unique single-atom-like coordination and electronic structure of Pt atoms in the Pt40Dy60 surface as responsible for enhanced ORR activity compared to the alloy with a higher Pt content. Additionally, Pt–Dy alloys showed activity in the oxygen evolution reaction (OER), with the OER current density lower than that of pure Pt.

Environmental Science and Pollution Research, 2022

ACS Omega, 2022

Nitrogenated graphene oxide-decorated copper sulfide nanocomposites (Cu x S-NrGO, where x = 1 and... more Nitrogenated graphene oxide-decorated copper sulfide nanocomposites (Cu x S-NrGO, where x = 1 and 2) are designed to be incorporated in polysulfone (PSF) membranes for effective fouling resistance of PSF membranes and their dye removal capacity. The developed membranes possess more hydrophilicity and an enhancement in pure water flux (PWF). Also, the highest bovine serum albumin (BSA) rejection of 89% was observed when compared to membranes with pristine PSF (5 L/m 2 h PWF and 88% BSA rejection) and CuS-incorporated PSF membranes (14 L/m 2 h PWF and 83% BSA rejection) because of N doping and enhanced permeability. It is also found that the Cu x S-NrGO-incorporated PSF membranes exhibited a significantly higher fouling resistance, a larger permeate flux recovery ratio (FRR) of nearly 82%, and a congo red dye rejection of 93%. Cu x S-NrGO nanoparticles thus demonstrate the potential efficacy of enhancing the hydrophilicity, leading to a better flux, dye removal capacity, and antifouling capacity with a very high FRR value of 82% because of a strong interaction between the N-active sites of the NrGO, Cu x S, and polysulfone matrix, and negligible leaching of nanoparticles is observed.

Advanced Composites and Hybrid Materials, 2022

Crystals, 2022

For specialized applications, it is incumbent to develop new materials that enable manufacturers ... more For specialized applications, it is incumbent to develop new materials that enable manufacturers to develop new processes and designs. For better fuel economy, structural integrity, and lightweight applications, the development of bimetallic steel/aluminum (Al) alloys having a strong interfacial bond is required. Therefore, a mild steel/Al-bearing alloy bimetallic composite was investigated in this study. Firstly, a tin (Sn) interlayer was developed between the steel substrate and the Al-bearing alloy by the tinning process. For further improvement in the interfacial integrity, alumina (Al2O3) nanoparticles were added to the Sn powder during the tinning process. Four different wt.% of Al2O3 nanoparticles of 0.25, 0.5, 1, and 1.5 were added and mixed thoroughly with Sn powder before mixing them with flux prior to the tinning process. Finally, molten Al-bearing alloy (Al–Sn-Si–Cu) was poured over the Al2O3 nanoparticles reinforced tinned steel substrate. A cross-section of the steel/A...

International Journal of Materials Technology and Innovation, 2021

Chemical Communications, 2019

In this work, a hydrazone chemistry assisted DNAzyme has been designed and constructed. With supe... more In this work, a hydrazone chemistry assisted DNAzyme has been designed and constructed. With superior catalyzed capability, hydrazone chemistry assisted DNAzyme has been successfully applied for analysis of double targets.

Journal of Materials Research and Technology, 2020

Herein, a simple hydrothermal rout was developed to produce highly efficient yttrium vanadate (YV... more Herein, a simple hydrothermal rout was developed to produce highly efficient yttrium vanadate (YVO 4) nanoparticles photocatalyst for catalytic degradation of methylene blue (MB) dye and phenol as color and colorless organics under UV illumination. The XRD results confirmed a crystalline, single phase of YVO 4 with a tetragonal structure at either 12 h (sample Y-12) or 24 h (sample Y-24) hydrothermal treatment. The mesoporous character was evaluated using N 2 sorption measurement. The TEM investigation revealed self-assembled <5 nm spherical nanoparticles with a silkworm cocoons-like structure with dimensions ∼40 × ∼90 nm for Y-12 photocatalyst, while Y-24 showed high density spherical nanoparticles with sizes between 4 and 15 nm. A maximum efficiency 98.5% MB degradation was achieved after 60 min. The reaction rate constant (k) of Y-24 photocatalyst was found to be 0.0615 min −1 which is almost 3.4 times larger than the k value for Degussa P-25 and 1.4 times higher than Y-12 photocatalyst. Furthermore, the photcatalytic degradation of phenol gives 93.2% after 120 min illumination. The chemical oxygen demand (COD) was measured to ensure the mineralization of both organic molecules. The effective photodegradation performance is likely related to the crystalline nature and textural properties with a high specific surface area of 140.8 m 2 /g. A suppression of charge recombination with improved charge separation was observed for the Y-24 sample during the photoluminescence spectra and transient photocurrent measurements. The optimal photocatalyst exhibited proper stability during the re-use and recyclability for five experimental runs.

ACS Omega, 2022

Nanostructured polymeric membranes are of great importance in enhancing the antifouling propertie... more Nanostructured polymeric membranes are of great importance in enhancing the antifouling properties during water filtration. Nanomaterials with tunable size, morphology and composition, surface modification, and increased functionality provide considerable opportunities for effective wastewater treatment. Thus, in this work, an attempt has been made to use spinelstructured MnCo 2 O 4 as a nanofiller in the fabrication of nanostructured polysulfone (PSF) mixed matrix membranes and is investigated in terms of morphology, hydrophilicity, permeability, protein and natural organic matter separation, dye removal, and, finally, antifouling properties. The MnCo 2 O 4 nanomaterials are synthesized and characterized via X-ray diffraction and field emission scanning electron microscopy and are loaded into a membrane matrix with varied concentrations (0 to 1.5 wt %). PSF nanocomposite membranes are prepared via a nonsolventinduced phase-separation process. The results show an enhancement in hydrophilicity, porosity, and permeability with respect to the modified nanocomposite membranes because of oxygen-rich species in the membrane matrix, which increases affinity toward water. It was also found that the modified membranes display remarkably greater pure water flux (PWF) (220 L/m 2 h), higher Congo red rejection coefficient (99.86%), higher humic acid removal (99.81%), higher fouling resistance, and a significant flux recovery ratio (FRR) (88%) when tested with bovine serum albumin protein when compared to a bare PSF membrane (30 L/m 2 h PWF and 35% FRR). This is because the addition of MnCo 2 O 4 nanoparticles into the polymeric casting solution yielded tighter PSF membranes with a denser skin layer and greater selectivity. Thus, the enhanced permeability, greater rejection coefficient, and antifouling properties show the promising potential of the fabricated PSF-spinel nanostructured membrane to be utilized in membrane technology for wastewater treatment.

Sensors (Basel, Switzerland), 2021

The power industry is in the process of grid modernization with the introduction of phasor measur... more The power industry is in the process of grid modernization with the introduction of phasor measurement units (PMUs), advanced metering infrastructure (AMI), and other technologies. Although these technologies enable more reliable and efficient operation, the risk of cyber threats has increased, as evidenced by the recent blackouts in Ukraine and New York. One of these threats is false data injection attacks (FDIAs). Most of the FDIA literature focuses on the vulnerability of DC estimators and AC estimators to such attacks. This paper investigates FDIAs for PMU-based state estimation, where the PMUs are comparable. Several states can be manipulated by compromising one PMU through the channels of that PMU. A Phase Locking Value (PLV) technique was developed to detect FDIAs. The proposed approach is tested on the IEEE 14-bus and the IEEE 30-bus test systems under different scenarios using a Monte Carlo simulation where the PLV demonstrated an efficient performance.

1 Promising Centre for Sensors and Electronic Devices (PCSED), Advanced Materials and NanoResearc... more 1 Promising Centre for Sensors and Electronic Devices (PCSED), Advanced Materials and NanoResearch Centre, Najran University, P.O. Box: 1988, Najran 11001, Saudi Arabia 2 Nanostructured Materials and Nanotechnology Division, Central Metallurgical Research and Development Institute (CMRDI), P.O. Box: 87 Helwan, Cairo 11421, Egypt 3 College of Science and Arts-Sharoura, Najran University, Saudi Arabia 4 Department of Physics, College of Science and Arts, Najran University, P.O. Box 1988, Najran 11001, Saudi Arabia * E-mail: fharraz68@yahoo.com

Herein, we report a rapid and highly effective methodology for the fabrication of active and stab... more Herein, we report a rapid and highly effective methodology for the fabrication of active and stable surface-enhanced Raman scattering (SERS) substrate by an electrochemical anodization and immersion plating routes. Porous silicon (PSi) layers were fabricated by the electrochemical anodization of a silicon wafer in ethanoic fluoride solution, followed by uniformly deposition of palladium nanoparticles (Pd NPs) via a simple immersion plating technique. The structural features and morphology of fabricated frameworks of PSi-Pd NPs have been investigated by field emission scanning electron microscopy (FE-SEM) with energy dispersive X-ray (EDX), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR) spectra. The PSi substrate demonstrates a meso-porous morphology with good distribution, good pore density and average pore sizes around 20 nm. The SERS performance of Si–Pd NPs and PSi–Pd NPs substrates has been examined taking imidacloprid (an ...

In this work, we demonstrate the use of annealed sol-gel derived ZnO nanoparticles acting as elec... more In this work, we demonstrate the use of annealed sol-gel derived ZnO nanoparticles acting as electron transport layer (ETL) in inverted bulk heterojunction (BHJ) polymer solar cells (PSCs). We have examined the photovoltaic performance of devices based on poly(2-methoxy-5-(2-ethylhexyloxy)p-phenylenevinylene) (MEH-PPV):(6,6)-phenyl-C61-butyric acid methyl ester (PC61BM) blend system employing the ZnO nanoparticles as an ETL with CuI as hole transport layer (HTL) in comparison to the case of using the conventional HTL of poly(3,4-ethylenedioxythiophene)/poly(styrene sulfonate) sulfonic acid (PEDOT:PSS). The effect of the presence of another layer of ZnO macrospheres attached to the ZnO nanoparticles is also investigated. The highest power conversion efficiency (PCE) value of 1.35% was achieved for device: ITO/ZnO nanoparticles/MEH-PPV:PC61BM/CuI/Ag, which is 275% more

Journal of Environmental Chemical Engineering

Journal of The Electrochemical Society

ACS Applied Materials & Interfaces

Radiation Physics and Chemistry

Biosensors

In this study, a selective 4-nitrophenol (4-NP) sensor was developed onto a glassy carbon electro... more In this study, a selective 4-nitrophenol (4-NP) sensor was developed onto a glassy carbon electrode (GCE) as an electron-sensing substrate, which decorated with sol–gel, prepared Pt nanoparticles- (NPs) embedded polypyrole-carbon black (PPy-CB)/ZnO nanocomposites (NCs) using differential pulse voltammetry. Characterizations of the NCs were performed using Field Emission Scanning Electron Microscopy (FESEM), Energy-Dispersive Spectroscopy (EDS), X-ray Photoelectron Spectroscopy (XPS), Ultraviolet–visible Spectroscopy (UV–vis), Fourier Transform Infrared Spectroscopy (FTIR), High Resolution Transmission Electron Microscopy (HRTEM), and X-ray Diffraction Analysis (XRD). The GCE modified by conducting coating binders [poly(3,4-ethylenedioxythiophene) polystyrene sulfonate; PEDOT:PSS] based on Pt NPs/PPy-CB/ZnO NCs functioned as the working electrode and showed selectivity toward 4-NP in a phosphate buffer medium at pH 7.0. Our analysis of 4-NP showed the linearity from 1.5 to 40.5 µM, w...

Nanomaterials

Copper-silver and cobalt-silver alloy nanoparticles deposited on reduced graphene oxide (CuAg/rGO... more Copper-silver and cobalt-silver alloy nanoparticles deposited on reduced graphene oxide (CuAg/rGO and CoAg/rGO) were synthesized and examined as electrocatalysts for oxygen reduction reaction (ORR) and hydrogen peroxide reduction reaction (HPRR) in alkaline media. Characterization of the prepared samples was done by transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction analysis (XRD), and scanning electron microscopy with integrated energy-dispersive X-ray spectroscopy (SEM-EDS). CuAg/rGO and CoAg/rGO nanoparticles diameter ranged from 0.4 to 9.2 nm. The Ag loading was ca. 40 wt.% for both electrocatalysts, with that for Cu and Co being 35 and 17 wt.%, respectively. CoAg/rGO electrocatalyst showed a Tafel slope of 109 mV dec−1, significantly lower than that for CuAg/rGO (184 mV dec−1), suggesting faster ORR kinetics. Additionally, a higher diffusion current density was obtained for CoAg/rGO (−2.63 mA cm−2) than ...

Nanomaterials

Platinum–dysprosium (Pt–Dy) alloys prepared by the arc melting technique are assessed as potentia... more Platinum–dysprosium (Pt–Dy) alloys prepared by the arc melting technique are assessed as potential electrodes for the oxygen reduction reaction (ORR) using voltammetry and chronoamperometry in alkaline media. A relatively small change (10 at.%) in the alloy composition brought a notable difference in the alloys’ performance for the ORR. Pt40Dy60 electrode, i.e., the electrode with a lower amount of Pt, was identified to have a higher activity towards ORR as evidenced by lower overpotential and higher current densities under identical experimental conditions. Furthermore, DFT calculations point out the unique single-atom-like coordination and electronic structure of Pt atoms in the Pt40Dy60 surface as responsible for enhanced ORR activity compared to the alloy with a higher Pt content. Additionally, Pt–Dy alloys showed activity in the oxygen evolution reaction (OER), with the OER current density lower than that of pure Pt.

Environmental Science and Pollution Research, 2022

ACS Omega, 2022

Nitrogenated graphene oxide-decorated copper sulfide nanocomposites (Cu x S-NrGO, where x = 1 and... more Nitrogenated graphene oxide-decorated copper sulfide nanocomposites (Cu x S-NrGO, where x = 1 and 2) are designed to be incorporated in polysulfone (PSF) membranes for effective fouling resistance of PSF membranes and their dye removal capacity. The developed membranes possess more hydrophilicity and an enhancement in pure water flux (PWF). Also, the highest bovine serum albumin (BSA) rejection of 89% was observed when compared to membranes with pristine PSF (5 L/m 2 h PWF and 88% BSA rejection) and CuS-incorporated PSF membranes (14 L/m 2 h PWF and 83% BSA rejection) because of N doping and enhanced permeability. It is also found that the Cu x S-NrGO-incorporated PSF membranes exhibited a significantly higher fouling resistance, a larger permeate flux recovery ratio (FRR) of nearly 82%, and a congo red dye rejection of 93%. Cu x S-NrGO nanoparticles thus demonstrate the potential efficacy of enhancing the hydrophilicity, leading to a better flux, dye removal capacity, and antifouling capacity with a very high FRR value of 82% because of a strong interaction between the N-active sites of the NrGO, Cu x S, and polysulfone matrix, and negligible leaching of nanoparticles is observed.

Advanced Composites and Hybrid Materials, 2022

Crystals, 2022

For specialized applications, it is incumbent to develop new materials that enable manufacturers ... more For specialized applications, it is incumbent to develop new materials that enable manufacturers to develop new processes and designs. For better fuel economy, structural integrity, and lightweight applications, the development of bimetallic steel/aluminum (Al) alloys having a strong interfacial bond is required. Therefore, a mild steel/Al-bearing alloy bimetallic composite was investigated in this study. Firstly, a tin (Sn) interlayer was developed between the steel substrate and the Al-bearing alloy by the tinning process. For further improvement in the interfacial integrity, alumina (Al2O3) nanoparticles were added to the Sn powder during the tinning process. Four different wt.% of Al2O3 nanoparticles of 0.25, 0.5, 1, and 1.5 were added and mixed thoroughly with Sn powder before mixing them with flux prior to the tinning process. Finally, molten Al-bearing alloy (Al–Sn-Si–Cu) was poured over the Al2O3 nanoparticles reinforced tinned steel substrate. A cross-section of the steel/A...

International Journal of Materials Technology and Innovation, 2021

Chemical Communications, 2019

In this work, a hydrazone chemistry assisted DNAzyme has been designed and constructed. With supe... more In this work, a hydrazone chemistry assisted DNAzyme has been designed and constructed. With superior catalyzed capability, hydrazone chemistry assisted DNAzyme has been successfully applied for analysis of double targets.

Journal of Materials Research and Technology, 2020

Herein, a simple hydrothermal rout was developed to produce highly efficient yttrium vanadate (YV... more Herein, a simple hydrothermal rout was developed to produce highly efficient yttrium vanadate (YVO 4) nanoparticles photocatalyst for catalytic degradation of methylene blue (MB) dye and phenol as color and colorless organics under UV illumination. The XRD results confirmed a crystalline, single phase of YVO 4 with a tetragonal structure at either 12 h (sample Y-12) or 24 h (sample Y-24) hydrothermal treatment. The mesoporous character was evaluated using N 2 sorption measurement. The TEM investigation revealed self-assembled <5 nm spherical nanoparticles with a silkworm cocoons-like structure with dimensions ∼40 × ∼90 nm for Y-12 photocatalyst, while Y-24 showed high density spherical nanoparticles with sizes between 4 and 15 nm. A maximum efficiency 98.5% MB degradation was achieved after 60 min. The reaction rate constant (k) of Y-24 photocatalyst was found to be 0.0615 min −1 which is almost 3.4 times larger than the k value for Degussa P-25 and 1.4 times higher than Y-12 photocatalyst. Furthermore, the photcatalytic degradation of phenol gives 93.2% after 120 min illumination. The chemical oxygen demand (COD) was measured to ensure the mineralization of both organic molecules. The effective photodegradation performance is likely related to the crystalline nature and textural properties with a high specific surface area of 140.8 m 2 /g. A suppression of charge recombination with improved charge separation was observed for the Y-24 sample during the photoluminescence spectra and transient photocurrent measurements. The optimal photocatalyst exhibited proper stability during the re-use and recyclability for five experimental runs.

ACS Omega, 2022

Nanostructured polymeric membranes are of great importance in enhancing the antifouling propertie... more Nanostructured polymeric membranes are of great importance in enhancing the antifouling properties during water filtration. Nanomaterials with tunable size, morphology and composition, surface modification, and increased functionality provide considerable opportunities for effective wastewater treatment. Thus, in this work, an attempt has been made to use spinelstructured MnCo 2 O 4 as a nanofiller in the fabrication of nanostructured polysulfone (PSF) mixed matrix membranes and is investigated in terms of morphology, hydrophilicity, permeability, protein and natural organic matter separation, dye removal, and, finally, antifouling properties. The MnCo 2 O 4 nanomaterials are synthesized and characterized via X-ray diffraction and field emission scanning electron microscopy and are loaded into a membrane matrix with varied concentrations (0 to 1.5 wt %). PSF nanocomposite membranes are prepared via a nonsolventinduced phase-separation process. The results show an enhancement in hydrophilicity, porosity, and permeability with respect to the modified nanocomposite membranes because of oxygen-rich species in the membrane matrix, which increases affinity toward water. It was also found that the modified membranes display remarkably greater pure water flux (PWF) (220 L/m 2 h), higher Congo red rejection coefficient (99.86%), higher humic acid removal (99.81%), higher fouling resistance, and a significant flux recovery ratio (FRR) (88%) when tested with bovine serum albumin protein when compared to a bare PSF membrane (30 L/m 2 h PWF and 35% FRR). This is because the addition of MnCo 2 O 4 nanoparticles into the polymeric casting solution yielded tighter PSF membranes with a denser skin layer and greater selectivity. Thus, the enhanced permeability, greater rejection coefficient, and antifouling properties show the promising potential of the fabricated PSF-spinel nanostructured membrane to be utilized in membrane technology for wastewater treatment.

Sensors (Basel, Switzerland), 2021

The power industry is in the process of grid modernization with the introduction of phasor measur... more The power industry is in the process of grid modernization with the introduction of phasor measurement units (PMUs), advanced metering infrastructure (AMI), and other technologies. Although these technologies enable more reliable and efficient operation, the risk of cyber threats has increased, as evidenced by the recent blackouts in Ukraine and New York. One of these threats is false data injection attacks (FDIAs). Most of the FDIA literature focuses on the vulnerability of DC estimators and AC estimators to such attacks. This paper investigates FDIAs for PMU-based state estimation, where the PMUs are comparable. Several states can be manipulated by compromising one PMU through the channels of that PMU. A Phase Locking Value (PLV) technique was developed to detect FDIAs. The proposed approach is tested on the IEEE 14-bus and the IEEE 30-bus test systems under different scenarios using a Monte Carlo simulation where the PLV demonstrated an efficient performance.

1 Promising Centre for Sensors and Electronic Devices (PCSED), Advanced Materials and NanoResearc... more 1 Promising Centre for Sensors and Electronic Devices (PCSED), Advanced Materials and NanoResearch Centre, Najran University, P.O. Box: 1988, Najran 11001, Saudi Arabia 2 Nanostructured Materials and Nanotechnology Division, Central Metallurgical Research and Development Institute (CMRDI), P.O. Box: 87 Helwan, Cairo 11421, Egypt 3 College of Science and Arts-Sharoura, Najran University, Saudi Arabia 4 Department of Physics, College of Science and Arts, Najran University, P.O. Box 1988, Najran 11001, Saudi Arabia * E-mail: fharraz68@yahoo.com

Herein, we report a rapid and highly effective methodology for the fabrication of active and stab... more Herein, we report a rapid and highly effective methodology for the fabrication of active and stable surface-enhanced Raman scattering (SERS) substrate by an electrochemical anodization and immersion plating routes. Porous silicon (PSi) layers were fabricated by the electrochemical anodization of a silicon wafer in ethanoic fluoride solution, followed by uniformly deposition of palladium nanoparticles (Pd NPs) via a simple immersion plating technique. The structural features and morphology of fabricated frameworks of PSi-Pd NPs have been investigated by field emission scanning electron microscopy (FE-SEM) with energy dispersive X-ray (EDX), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR) spectra. The PSi substrate demonstrates a meso-porous morphology with good distribution, good pore density and average pore sizes around 20 nm. The SERS performance of Si–Pd NPs and PSi–Pd NPs substrates has been examined taking imidacloprid (an ...

In this work, we demonstrate the use of annealed sol-gel derived ZnO nanoparticles acting as elec... more In this work, we demonstrate the use of annealed sol-gel derived ZnO nanoparticles acting as electron transport layer (ETL) in inverted bulk heterojunction (BHJ) polymer solar cells (PSCs). We have examined the photovoltaic performance of devices based on poly(2-methoxy-5-(2-ethylhexyloxy)p-phenylenevinylene) (MEH-PPV):(6,6)-phenyl-C61-butyric acid methyl ester (PC61BM) blend system employing the ZnO nanoparticles as an ETL with CuI as hole transport layer (HTL) in comparison to the case of using the conventional HTL of poly(3,4-ethylenedioxythiophene)/poly(styrene sulfonate) sulfonic acid (PEDOT:PSS). The effect of the presence of another layer of ZnO macrospheres attached to the ZnO nanoparticles is also investigated. The highest power conversion efficiency (PCE) value of 1.35% was achieved for device: ITO/ZnO nanoparticles/MEH-PPV:PC61BM/CuI/Ag, which is 275% more

Journal of Environmental Chemical Engineering

Journal of The Electrochemical Society

ACS Applied Materials & Interfaces

Radiation Physics and Chemistry