Recently, the nanostructured nickel–cobalt bimetallic oxide (NiCo2O4) material with high electroc... more Recently, the nanostructured nickel–cobalt bimetallic oxide (NiCo2O4) material with high electrochemical activity has received intensive attention.
The preparation of Co3O4 nanostructures by a green method has been rapidly increasing owing to it... more The preparation of Co3O4 nanostructures by a green method has been rapidly increasing owing to its promising aspects, such as facileness, atom economy, low cost, scale-up synthesis, environmental friendliness, and minimal use of hazardous chemicals.
In this study, a simple approach was used to produce nonprecious, earth abundant, stable and envi... more In this study, a simple approach was used to produce nonprecious, earth abundant, stable and environmentally friendly NiCo2O4/CuO composites for the oxygen evolution reaction (OER) in alkaline media.
We have fabricated ZnO nano rods by hydrothermal method and successively doped them with tin (Sn)... more We have fabricated ZnO nano rods by hydrothermal method and successively doped them with tin (Sn) using different concentrations of 25, 50, 75 and 100 mg of tin chloride. XRD of the fabricated structures showed that ZnO possess hexagonal wurtzite phase. Scanning electron microscopy (SEM) was used to explore the morphology and it shows nanorod like morphology for all samples and no considerable change in the structural features were found. The dimension of nanorod is 200 to 300 nm. The doped materials were then investigated for their photo catalytic degradation of environmental pollutant Rhodamine B. The performance of doped ZnO is compared with the pristine ZnO. Scanning electron microscopy (SEM) was used to explore the morphology and it shows nanorod like morphology for all samples and no considerable change in the structural features were found. The dimension of nanorod is 200 to 300 nm. XRD of the fabricated structures showed that ZnO possess hexagonal wurtzite phase. Photo catal...
An efficient, simple, environment-friendly and inexpensive cupric oxide (CuO) electrocatalyst for... more An efficient, simple, environment-friendly and inexpensive cupric oxide (CuO) electrocatalyst for oxygen evolution reaction (OER) is demonstrated. CuO is chemically deposited on the porous carbon material obtained from the dehydration of common sugar. The morphology of CuO on the porous carbon material is plate-like and monoclinic crystalline phase is confirmed by powder X-ray diffraction. The OER activity of CuO nanostructures is investigated in 1 M KOH aqueous solution. To date, the proposed electrocatalyst has the lowest possible potential of 1.49 V versus RHE (reversible hydrogen electrode) to achieve a current density of 20 mA/cm₂ among the CuO based electrocatalysts and has Tafel slope of 115 mV dec-1. The electrocatalyst exhibits an excellent long-term stability for 6 hours along with significant durability. The enhanced catalytic active centers of CuO on the carbon material are due to the porous structure of carbon as well as strong coupling between CuO-C. The functionalizat...
Efficient hydrogen evolution reaction (HER) catalysts based on the earth-abundant materials are h... more Efficient hydrogen evolution reaction (HER) catalysts based on the earth-abundant materials are highly vital to design practical and environmentally friendly water splitting devices. In this study, we present an optimized strategy for the development of active catalysts for hydrogen evolution reaction HER. The composite catalysts are prepared with the nanosurface of NiO for the deposition of NiS by hydrothermal method. In alkaline electrolyte, the NiS/NiO nanocomposite has shown excellent catalytic HER properties at the low onset potential and small Tafel slope of 72 mVdec-1. A current density of 10 mA/cm² is achieved by the nanocomposite obtained with 0.4 gram of NiO as nanosurface for the deposition of NiS (sample 4) at the cost of 429 mV versus RHE. The sample 4 carries more active sites that allow it to act as excellent HER catalyst. Based on this study, we conclude that increasing the nickel oxide content into composite sample facilitates the HER process. Additionally, a long t...
In this research work, we have produced a composite material consisting titanium dioxide (TiO₂) a... more In this research work, we have produced a composite material consisting titanium dioxide (TiO₂) and zinc oxide (ZnO) nanostructures via precipitation method. Scanning electron microscopy (SEM) study has shown the mixture of nanostructures consisting nanorods and nano flower. Energy dispersive spectroscopy (EDS) study has confirmed the presence of Ti, Zn and O as main elements in the composite. X-ray diffraction (XRD) study has revealed that the successful presence of TiO₂ and ZnO in the composite. The composite material exhibits small optical energy band gap which led to reduction of the charge recombination rate of electron-hole pairs. The band gap for the composite TiO₂/ZnO samples namely 1, 2, 3 and 4 is 3.18, 3.00, 2.97 and 2.83 eV respectively. Small optical bandgap gives less relaxation time for the recombination of electron and hole pairs, thus favorable photodegradation is found. The degradation efficiency for the TiO₂/ZnO samples for methylene blue in order of 55.03%, 75.7%...
In this research work, we have produced tungsten (W) doped ZnO nanostructures via low-temperature... more In this research work, we have produced tungsten (W) doped ZnO nanostructures via low-temperature aqueous chemical growth method. The morphology, crystal arrays and composition was investigated by scanning electron microscopy (SEM), powder X-ray diffraction (XRD) and energy dispersive X-rays (EDX) respectively. The SEM results indicate the nanowire morphology before and after the doping of W into ZnO and XRD study has shown the hexagonal crystallography of W doped ZnO samples. The EDX study has confirmed the successful doping of W into ZnO crystal lattices. The photodegradation performance of methylene blue was evaluated with W doped ZnO samples and pristine ZnO in aqueous solution. The measured degradation efficiencies for the different W doped ZnO samples were 5 wt%, 10 wt%, 15 wt% and 20 wt% at pH 5 are 87.8%, 92.3%, 92.8% and 96.9%), at pH 9 (72.1%, 90.7%, 92.1%, and 96.4%) and at pH 11 (80%, 85%, 87% and 89%) for the time interval of 90 min respectively. The pH of dye solution ...
Cobalt oxide has been widely investigated among potential transition metal oxides for the electro... more Cobalt oxide has been widely investigated among potential transition metal oxides for the electrochemical energy conversion, storage, and water splitting. However, they have inherently low electronic conductivity and high corrosive nature in alkaline media. Herein, we propose a promising and facile approach to improve the conductivity and charge transport of cobalt oxide Co3O4 through chemical coupling with well-dispersed multiwall carbon nanotubes (MWCNTs) during hydrothermal treatment. The morphology of prepared composite material consisting of nanosheets which are anchored on the MWCNTs as confirmed by scanning electron microscopy (SEM). A cubic crystalline system is exhibited by the cobalt oxide as confirmed by the X-ray diffraction study. The Co, O, and C are the only elements present in the composite material. FTIR study has indicated the successful coupling of cobalt oxide with MWCNTs. The chemically coupled cobalt oxide onto the surface of MWCNTs composite is found highly ac...
Designing an efficient electrocatalyst for the oxygen evolution reaction (OER) in alkaline media ... more Designing an efficient electrocatalyst for the oxygen evolution reaction (OER) in alkaline media is highly needed but very challenging task. Herein, we used organic polyelectrolytes such as (carboxymethyl cellulose) CMC and polyacrylamide polymers for the growth of Co3O4 nanostructures by aqueous chemical growth method. The morphology and composition studies were performed on scanning electron microscopy (SEM), energy dispersive X-ray (EDX), powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and high-resolution transmission electron microscopy (HRTEM) techniques. The structural properties and the surface chemistry of the Co3O4 electrocatalysts were correlated to the OER performance, and the enhancement mechanism with respect to pristine Co3O4 was observed to be specifically related to the polyelectrolyte templating role.
Co3O4@CMC composites displayed reduced crystallite size, producing OER overpotential as low as 290 mV at 10 mAcm−2 in 1.0 KOH and Tafel slope of 71 mVdec−1, suggesting fast transfer of intermediates and electrons during water electrolysis. On the other hand, the use of polyacrylamide and its different templating mechanism resulted in similar crystallite size, but preferential exposed faces and larger surface vacancies content, as demonstrated by HR-TEM and XPS, respectively. Consistently, this material displays cutting-edge OER performance, such as overpotential of 260 mV at 10 mAcm−2 and a low Tafel slope of 63 mVdec−1. The proposed strategy for the preparation of Co3O4 nanostructures in the presence of CMC and polyacrylamide is facile, mass production, thus it could equally contributed towards the realization of hydrogen energy. Therefore, these nanostructures of Co3O4 can be regarded as an alternative and promising materials for the different electrochemical applications including fuel cells, metal air batteries, overall water electrolysis and other energy storage devices.
The design of efficient, stable, durable and noble metal free electro catalysts for oxygen evolut... more The design of efficient, stable, durable and noble metal free electro catalysts for oxygen evolution reaction (OER) are of immediate need, but very challenging task. In this study, iron induction into cobalt oxide (Co3O4) has resulted composite structure by wet chemical method. The iron impurity has brought an electronic disorder into Fe3O4/cobalt oxide composite thereby efficient oxygen evolution reaction is demonstrated. An addition of iron content into composite resulted the alternation of morphology from Nano rods to clusters of nanoparticles. The successive addition of iron into composite system reduced the onset potential of OER as compared to the pristine cobalt oxide. A Tafel slope of 80 mVdec-1 indicates the favorable oxygen evolution reaction kinetics on the sample 4. An over-potential of 370 mV is required to reach a 10 mAcm-2 current density which is acceptable for a nonprecious catalyst. The catalyst is highly durable and stable for 30 hours. Electrochemical impedance s...
Designing a facile and low-cost methodology to fabricate earth-abundant catalysts is very much ne... more Designing a facile and low-cost methodology to fabricate earth-abundant catalysts is very much needed for a wide range of applications.
Recently, the nanostructured nickel–cobalt bimetallic oxide (NiCo2O4) material with high electroc... more Recently, the nanostructured nickel–cobalt bimetallic oxide (NiCo2O4) material with high electrochemical activity has received intensive attention.
The preparation of Co3O4 nanostructures by a green method has been rapidly increasing owing to it... more The preparation of Co3O4 nanostructures by a green method has been rapidly increasing owing to its promising aspects, such as facileness, atom economy, low cost, scale-up synthesis, environmental friendliness, and minimal use of hazardous chemicals.
In this study, a simple approach was used to produce nonprecious, earth abundant, stable and envi... more In this study, a simple approach was used to produce nonprecious, earth abundant, stable and environmentally friendly NiCo2O4/CuO composites for the oxygen evolution reaction (OER) in alkaline media.
We have fabricated ZnO nano rods by hydrothermal method and successively doped them with tin (Sn)... more We have fabricated ZnO nano rods by hydrothermal method and successively doped them with tin (Sn) using different concentrations of 25, 50, 75 and 100 mg of tin chloride. XRD of the fabricated structures showed that ZnO possess hexagonal wurtzite phase. Scanning electron microscopy (SEM) was used to explore the morphology and it shows nanorod like morphology for all samples and no considerable change in the structural features were found. The dimension of nanorod is 200 to 300 nm. The doped materials were then investigated for their photo catalytic degradation of environmental pollutant Rhodamine B. The performance of doped ZnO is compared with the pristine ZnO. Scanning electron microscopy (SEM) was used to explore the morphology and it shows nanorod like morphology for all samples and no considerable change in the structural features were found. The dimension of nanorod is 200 to 300 nm. XRD of the fabricated structures showed that ZnO possess hexagonal wurtzite phase. Photo catal...
An efficient, simple, environment-friendly and inexpensive cupric oxide (CuO) electrocatalyst for... more An efficient, simple, environment-friendly and inexpensive cupric oxide (CuO) electrocatalyst for oxygen evolution reaction (OER) is demonstrated. CuO is chemically deposited on the porous carbon material obtained from the dehydration of common sugar. The morphology of CuO on the porous carbon material is plate-like and monoclinic crystalline phase is confirmed by powder X-ray diffraction. The OER activity of CuO nanostructures is investigated in 1 M KOH aqueous solution. To date, the proposed electrocatalyst has the lowest possible potential of 1.49 V versus RHE (reversible hydrogen electrode) to achieve a current density of 20 mA/cm₂ among the CuO based electrocatalysts and has Tafel slope of 115 mV dec-1. The electrocatalyst exhibits an excellent long-term stability for 6 hours along with significant durability. The enhanced catalytic active centers of CuO on the carbon material are due to the porous structure of carbon as well as strong coupling between CuO-C. The functionalizat...
Efficient hydrogen evolution reaction (HER) catalysts based on the earth-abundant materials are h... more Efficient hydrogen evolution reaction (HER) catalysts based on the earth-abundant materials are highly vital to design practical and environmentally friendly water splitting devices. In this study, we present an optimized strategy for the development of active catalysts for hydrogen evolution reaction HER. The composite catalysts are prepared with the nanosurface of NiO for the deposition of NiS by hydrothermal method. In alkaline electrolyte, the NiS/NiO nanocomposite has shown excellent catalytic HER properties at the low onset potential and small Tafel slope of 72 mVdec-1. A current density of 10 mA/cm² is achieved by the nanocomposite obtained with 0.4 gram of NiO as nanosurface for the deposition of NiS (sample 4) at the cost of 429 mV versus RHE. The sample 4 carries more active sites that allow it to act as excellent HER catalyst. Based on this study, we conclude that increasing the nickel oxide content into composite sample facilitates the HER process. Additionally, a long t...
In this research work, we have produced a composite material consisting titanium dioxide (TiO₂) a... more In this research work, we have produced a composite material consisting titanium dioxide (TiO₂) and zinc oxide (ZnO) nanostructures via precipitation method. Scanning electron microscopy (SEM) study has shown the mixture of nanostructures consisting nanorods and nano flower. Energy dispersive spectroscopy (EDS) study has confirmed the presence of Ti, Zn and O as main elements in the composite. X-ray diffraction (XRD) study has revealed that the successful presence of TiO₂ and ZnO in the composite. The composite material exhibits small optical energy band gap which led to reduction of the charge recombination rate of electron-hole pairs. The band gap for the composite TiO₂/ZnO samples namely 1, 2, 3 and 4 is 3.18, 3.00, 2.97 and 2.83 eV respectively. Small optical bandgap gives less relaxation time for the recombination of electron and hole pairs, thus favorable photodegradation is found. The degradation efficiency for the TiO₂/ZnO samples for methylene blue in order of 55.03%, 75.7%...
In this research work, we have produced tungsten (W) doped ZnO nanostructures via low-temperature... more In this research work, we have produced tungsten (W) doped ZnO nanostructures via low-temperature aqueous chemical growth method. The morphology, crystal arrays and composition was investigated by scanning electron microscopy (SEM), powder X-ray diffraction (XRD) and energy dispersive X-rays (EDX) respectively. The SEM results indicate the nanowire morphology before and after the doping of W into ZnO and XRD study has shown the hexagonal crystallography of W doped ZnO samples. The EDX study has confirmed the successful doping of W into ZnO crystal lattices. The photodegradation performance of methylene blue was evaluated with W doped ZnO samples and pristine ZnO in aqueous solution. The measured degradation efficiencies for the different W doped ZnO samples were 5 wt%, 10 wt%, 15 wt% and 20 wt% at pH 5 are 87.8%, 92.3%, 92.8% and 96.9%), at pH 9 (72.1%, 90.7%, 92.1%, and 96.4%) and at pH 11 (80%, 85%, 87% and 89%) for the time interval of 90 min respectively. The pH of dye solution ...
Cobalt oxide has been widely investigated among potential transition metal oxides for the electro... more Cobalt oxide has been widely investigated among potential transition metal oxides for the electrochemical energy conversion, storage, and water splitting. However, they have inherently low electronic conductivity and high corrosive nature in alkaline media. Herein, we propose a promising and facile approach to improve the conductivity and charge transport of cobalt oxide Co3O4 through chemical coupling with well-dispersed multiwall carbon nanotubes (MWCNTs) during hydrothermal treatment. The morphology of prepared composite material consisting of nanosheets which are anchored on the MWCNTs as confirmed by scanning electron microscopy (SEM). A cubic crystalline system is exhibited by the cobalt oxide as confirmed by the X-ray diffraction study. The Co, O, and C are the only elements present in the composite material. FTIR study has indicated the successful coupling of cobalt oxide with MWCNTs. The chemically coupled cobalt oxide onto the surface of MWCNTs composite is found highly ac...
Designing an efficient electrocatalyst for the oxygen evolution reaction (OER) in alkaline media ... more Designing an efficient electrocatalyst for the oxygen evolution reaction (OER) in alkaline media is highly needed but very challenging task. Herein, we used organic polyelectrolytes such as (carboxymethyl cellulose) CMC and polyacrylamide polymers for the growth of Co3O4 nanostructures by aqueous chemical growth method. The morphology and composition studies were performed on scanning electron microscopy (SEM), energy dispersive X-ray (EDX), powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and high-resolution transmission electron microscopy (HRTEM) techniques. The structural properties and the surface chemistry of the Co3O4 electrocatalysts were correlated to the OER performance, and the enhancement mechanism with respect to pristine Co3O4 was observed to be specifically related to the polyelectrolyte templating role.
Co3O4@CMC composites displayed reduced crystallite size, producing OER overpotential as low as 290 mV at 10 mAcm−2 in 1.0 KOH and Tafel slope of 71 mVdec−1, suggesting fast transfer of intermediates and electrons during water electrolysis. On the other hand, the use of polyacrylamide and its different templating mechanism resulted in similar crystallite size, but preferential exposed faces and larger surface vacancies content, as demonstrated by HR-TEM and XPS, respectively. Consistently, this material displays cutting-edge OER performance, such as overpotential of 260 mV at 10 mAcm−2 and a low Tafel slope of 63 mVdec−1. The proposed strategy for the preparation of Co3O4 nanostructures in the presence of CMC and polyacrylamide is facile, mass production, thus it could equally contributed towards the realization of hydrogen energy. Therefore, these nanostructures of Co3O4 can be regarded as an alternative and promising materials for the different electrochemical applications including fuel cells, metal air batteries, overall water electrolysis and other energy storage devices.
The design of efficient, stable, durable and noble metal free electro catalysts for oxygen evolut... more The design of efficient, stable, durable and noble metal free electro catalysts for oxygen evolution reaction (OER) are of immediate need, but very challenging task. In this study, iron induction into cobalt oxide (Co3O4) has resulted composite structure by wet chemical method. The iron impurity has brought an electronic disorder into Fe3O4/cobalt oxide composite thereby efficient oxygen evolution reaction is demonstrated. An addition of iron content into composite resulted the alternation of morphology from Nano rods to clusters of nanoparticles. The successive addition of iron into composite system reduced the onset potential of OER as compared to the pristine cobalt oxide. A Tafel slope of 80 mVdec-1 indicates the favorable oxygen evolution reaction kinetics on the sample 4. An over-potential of 370 mV is required to reach a 10 mAcm-2 current density which is acceptable for a nonprecious catalyst. The catalyst is highly durable and stable for 30 hours. Electrochemical impedance s...
Designing a facile and low-cost methodology to fabricate earth-abundant catalysts is very much ne... more Designing a facile and low-cost methodology to fabricate earth-abundant catalysts is very much needed for a wide range of applications.
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Papers by adeel bhatti
Co3O4@CMC composites displayed reduced crystallite size, producing OER overpotential as low as 290 mV at 10 mAcm−2 in 1.0 KOH and Tafel slope of 71 mVdec−1, suggesting fast transfer of intermediates and electrons during water electrolysis. On the other hand, the use of polyacrylamide and its different templating mechanism resulted in similar crystallite size, but preferential exposed faces and larger surface vacancies content, as demonstrated by HR-TEM and XPS, respectively. Consistently, this material displays cutting-edge OER performance, such as overpotential of 260 mV at 10 mAcm−2 and a low Tafel slope of 63 mVdec−1. The proposed strategy for the preparation of Co3O4 nanostructures in the presence of CMC and polyacrylamide is facile, mass production, thus it could equally contributed towards the realization of hydrogen energy. Therefore, these nanostructures of Co3O4 can be regarded as an alternative and promising materials for the different electrochemical applications including fuel cells, metal air batteries, overall water electrolysis and other energy storage devices.
Co3O4@CMC composites displayed reduced crystallite size, producing OER overpotential as low as 290 mV at 10 mAcm−2 in 1.0 KOH and Tafel slope of 71 mVdec−1, suggesting fast transfer of intermediates and electrons during water electrolysis. On the other hand, the use of polyacrylamide and its different templating mechanism resulted in similar crystallite size, but preferential exposed faces and larger surface vacancies content, as demonstrated by HR-TEM and XPS, respectively. Consistently, this material displays cutting-edge OER performance, such as overpotential of 260 mV at 10 mAcm−2 and a low Tafel slope of 63 mVdec−1. The proposed strategy for the preparation of Co3O4 nanostructures in the presence of CMC and polyacrylamide is facile, mass production, thus it could equally contributed towards the realization of hydrogen energy. Therefore, these nanostructures of Co3O4 can be regarded as an alternative and promising materials for the different electrochemical applications including fuel cells, metal air batteries, overall water electrolysis and other energy storage devices.