Adsorptive removal of Congo red dye from aqueous media has been carried out by using sawdust of C... more Adsorptive removal of Congo red dye from aqueous media has been carried out by using sawdust of Cedrus deodara saw as an efficient adsorbent by evaluating different parameters such as adsorbent dosage, contact time, pH, initial dye concentration, and temperature at constant shaking time of five minutes by using a Benchtop orbital shaker to homogenize adsorption medium that develops more attractive forces between C. deodara saw and dye molecules lead to higher adsorption values. The C. deodara saw surface morphology was monitored by Fourier transform infra-red spectroscopy and scanning electron microscopy analysis. The adsorption experimental data was studied by applying the Langmuir, Freundlich, and Dubinin–Radushkevich isothermal models, and data was well obeyed by D–R isotherm based on R2 and SSE (0.996, 0.004) values. The kinetics of the adsorption process was investigated by pseudo-first-order, pseudo-second-order, liquid film, and intra-particle diffusion models. Kinetics indic...
Abstract Benefiting from the controlled hydrothermal synthesis of tungsten trioxide (WO3) nanoshe... more Abstract Benefiting from the controlled hydrothermal synthesis of tungsten trioxide (WO3) nanosheets (NSs), a unique thin-film back contact was designed for the CdTe solar cells. The hydrothermally prepared WO3 NSs was spin-coated as the thin-film buffer layer on the back contact of CdTe thin-film solar cells to replace traditional Cu contact. The morphology, phase crystallization, chemical compositions, and the intimate junction contact were confirmed by SEM, TEM, XRD, Raman, and XPS characterizations. The interpretation of the quantitative band alignment carried out on an X-ray photoelectron spectroscopy (XPS) showed that the WO3/CdTe energy barrier at the interface was substantially lower. The offset of the valence band (∆EVBO) and conduction band (∆ECBO) at WO3/CdTe heterojunction were found 0.69 and 1.86 eV respectively. Moreover, by combining WO3 as a high work-function buffer layer with various metals contacts such as Au, WO3/Au, Cu/WO3/Au, and the conventional Cu/Au metal layer, low resistive ohmic back contacts for CdTe thin-film solar cells were developed and analyzed. Interestingly, the CdTe thin-film solar cells fabricated with WO3 NSs as a buffer layer between CdTe/Cu (3 nm) and metallic Au electrodes demonstrated the best performance with the conversion efficiency of 13.0%. To the best of our knowledge, so far this is the first report on WO3 NSs that opened a new paradigm to use WO3 nanostructures as a buffer layer in the thin-film CdTe solar cell to get improved thermal stability and device efficiency in the harsh environment.
Abstract Carbon nanofibers (CNFs) based thin films were introduced as a buffer layer in the back ... more Abstract Carbon nanofibers (CNFs) based thin films were introduced as a buffer layer in the back contact of of CdTe thin film solar cells. CNFs buffer layer is used to replace the conventional metal contact layer. Quantitative band alignment measurement by using X-ray photoelectron spectroscopy (XPS) demonstrated that a relatively low energy barrier at the CNF/CdTe interface was formed. The valance band offset of 0.47 eV and conduction band offset of 0.80 eV were examined between CNF and CdTe.. The stability of CdTe solar cells was considerably improved by introducing CNF buffer layer with trace amount of Cu to fabricate low-energy barrier back contact. The CNFs as a buffer layer between CdTe and metal Au electrode based fabricated CdTe thin film solar cells demonstrated a conversion efficiency of 11.4 %. From the device stability stressing tests we conclude that CNFs as a buffer layer in a CdTe thin film solar cell meaningfully improved the cell performance and device stability.
Introduction: Left ventricular diastolic dysfunction (DD) is an entity in which the ventricle fai... more Introduction: Left ventricular diastolic dysfunction (DD) is an entity in which the ventricle fails to fill up properly due to impaired ventricular relaxation and/or decreased compliance. The diagnosis of diastolic dysfunction is based on a variety of parameters in doppler echocardiograpy. However, some parameters like interventricular septal thickness in diastole (IVSd), posterior wall thickness in diastole (PWd), left ventricular internal end diastolic and systolic diameters (LVIDD and LVISD) along with left atrial diameters (LAD) have yet to be evaluated for the diagnostic workup of DD. Methods: A case control study was done in the cardiology department from patient records from 2016 to 2018. Patients were diagnosed as diastolic dysfunction grade II and above by doppler echocardiography. IVSd, PWd, LVIDD, LAD, LVISD were obtained through 2-D echocardiography. Results: Patients with DD had greater LAD, IVSd and PWd and decreased LVIDD and LVISD as compared to control group. Overal...
NFC IEFR Journal of Engineering and Scientific Research, 2019
Wastewater of textile industry having impurities and heavy metal ions cause problems in human soc... more Wastewater of textile industry having impurities and heavy metal ions cause problems in human society that can endanger the human health through food chain. Adsorption of heavy metal ions before draining makes wastewater safe for aquatic life and human health. Now a day’s adsorption of heavy metal through polymeric nano adsorbents is the emerging technology which is more efficient than conventional adsorbents like activated carbon. The pH 9.0 gave maximum 96% sorption of Co at 1.0 g/L adsorbent dosage, due to increased electrostatic force of attraction produced by the negative charge at the surface of sorbent which is favorable for adsorbing cationic species. In the beginning of15 minute retention time, metal ions adsorption was rapid due to availability of more number of adsorptive sites but further increase of retention time decreased the sorption capacity due to partial desorption that may occur due to the charge density and diameter of hydrated ions. Similarly in case of Cu, the...
The magnetic property in a material is induced by the unpaired electrons. This can occur due to d... more The magnetic property in a material is induced by the unpaired electrons. This can occur due to defect states which can enhance the magnetic moment and the spin polarization. In this report, CdS and CdTe thin films are grown on FTO glass substrates by chemical bath deposition and close-spaced sublimation, respectively. The magnetic properties, which are introduced from oxygen states, are found in CdS and CdTe thin films. From the hysteresis loop of magnetic moment it is revealed that CdS and CdTe thin films have different kinds of magnetic moments at different temperatures. The M–H curves indicate that from 100 K to 350 K, CdS and CdTe thin films show paramagnetism and diamagnetism, respectively. A superparamagnetic or a weakly ferromagnetic response is found at 5 K. It is also observed from ZFC/FC curves that magnetic moments decrease with temperature increasing. Spin polarized density functional calculation for spin magnetic moment is also carried out.
Langmuir : the ACS journal of surfaces and colloids, May 10, 2017
We demonstrate a hetero-structure Ni9S8/MoS2 hybrid with tight interface synthesized via an impro... more We demonstrate a hetero-structure Ni9S8/MoS2 hybrid with tight interface synthesized via an improved hydrothermal method. As compared to pure MoS2, the increased surface area and the shorten charge transport pathway in the layered hybrid significantly promote the photocatalytic efficiency for hydrogen evolution reaction (HER). In particularly, the optimized Ni9S8/MoS2 hybrid with 20 wt% Ni9S8 exhibits the highest photocatalytic activity with HER value of 406 μmolg-1h-1, which is enhanced by 70% compared to that of pure MoS2 nanosheets (285.0 μmolg-1h-1). Moreover, the value is 4 times more than the commercial MoS2 (92.0 μmolg-1h-1), indicating the high potential of the hybrid in the catalytic fields.
Adsorptive removal of Congo red dye from aqueous media has been carried out by using sawdust of C... more Adsorptive removal of Congo red dye from aqueous media has been carried out by using sawdust of Cedrus deodara saw as an efficient adsorbent by evaluating different parameters such as adsorbent dosage, contact time, pH, initial dye concentration, and temperature at constant shaking time of five minutes by using a Benchtop orbital shaker to homogenize adsorption medium that develops more attractive forces between C. deodara saw and dye molecules lead to higher adsorption values. The C. deodara saw surface morphology was monitored by Fourier transform infra-red spectroscopy and scanning electron microscopy analysis. The adsorption experimental data was studied by applying the Langmuir, Freundlich, and Dubinin–Radushkevich isothermal models, and data was well obeyed by D–R isotherm based on R2 and SSE (0.996, 0.004) values. The kinetics of the adsorption process was investigated by pseudo-first-order, pseudo-second-order, liquid film, and intra-particle diffusion models. Kinetics indic...
Abstract Benefiting from the controlled hydrothermal synthesis of tungsten trioxide (WO3) nanoshe... more Abstract Benefiting from the controlled hydrothermal synthesis of tungsten trioxide (WO3) nanosheets (NSs), a unique thin-film back contact was designed for the CdTe solar cells. The hydrothermally prepared WO3 NSs was spin-coated as the thin-film buffer layer on the back contact of CdTe thin-film solar cells to replace traditional Cu contact. The morphology, phase crystallization, chemical compositions, and the intimate junction contact were confirmed by SEM, TEM, XRD, Raman, and XPS characterizations. The interpretation of the quantitative band alignment carried out on an X-ray photoelectron spectroscopy (XPS) showed that the WO3/CdTe energy barrier at the interface was substantially lower. The offset of the valence band (∆EVBO) and conduction band (∆ECBO) at WO3/CdTe heterojunction were found 0.69 and 1.86 eV respectively. Moreover, by combining WO3 as a high work-function buffer layer with various metals contacts such as Au, WO3/Au, Cu/WO3/Au, and the conventional Cu/Au metal layer, low resistive ohmic back contacts for CdTe thin-film solar cells were developed and analyzed. Interestingly, the CdTe thin-film solar cells fabricated with WO3 NSs as a buffer layer between CdTe/Cu (3 nm) and metallic Au electrodes demonstrated the best performance with the conversion efficiency of 13.0%. To the best of our knowledge, so far this is the first report on WO3 NSs that opened a new paradigm to use WO3 nanostructures as a buffer layer in the thin-film CdTe solar cell to get improved thermal stability and device efficiency in the harsh environment.
Abstract Carbon nanofibers (CNFs) based thin films were introduced as a buffer layer in the back ... more Abstract Carbon nanofibers (CNFs) based thin films were introduced as a buffer layer in the back contact of of CdTe thin film solar cells. CNFs buffer layer is used to replace the conventional metal contact layer. Quantitative band alignment measurement by using X-ray photoelectron spectroscopy (XPS) demonstrated that a relatively low energy barrier at the CNF/CdTe interface was formed. The valance band offset of 0.47 eV and conduction band offset of 0.80 eV were examined between CNF and CdTe.. The stability of CdTe solar cells was considerably improved by introducing CNF buffer layer with trace amount of Cu to fabricate low-energy barrier back contact. The CNFs as a buffer layer between CdTe and metal Au electrode based fabricated CdTe thin film solar cells demonstrated a conversion efficiency of 11.4 %. From the device stability stressing tests we conclude that CNFs as a buffer layer in a CdTe thin film solar cell meaningfully improved the cell performance and device stability.
Introduction: Left ventricular diastolic dysfunction (DD) is an entity in which the ventricle fai... more Introduction: Left ventricular diastolic dysfunction (DD) is an entity in which the ventricle fails to fill up properly due to impaired ventricular relaxation and/or decreased compliance. The diagnosis of diastolic dysfunction is based on a variety of parameters in doppler echocardiograpy. However, some parameters like interventricular septal thickness in diastole (IVSd), posterior wall thickness in diastole (PWd), left ventricular internal end diastolic and systolic diameters (LVIDD and LVISD) along with left atrial diameters (LAD) have yet to be evaluated for the diagnostic workup of DD. Methods: A case control study was done in the cardiology department from patient records from 2016 to 2018. Patients were diagnosed as diastolic dysfunction grade II and above by doppler echocardiography. IVSd, PWd, LVIDD, LAD, LVISD were obtained through 2-D echocardiography. Results: Patients with DD had greater LAD, IVSd and PWd and decreased LVIDD and LVISD as compared to control group. Overal...
NFC IEFR Journal of Engineering and Scientific Research, 2019
Wastewater of textile industry having impurities and heavy metal ions cause problems in human soc... more Wastewater of textile industry having impurities and heavy metal ions cause problems in human society that can endanger the human health through food chain. Adsorption of heavy metal ions before draining makes wastewater safe for aquatic life and human health. Now a day’s adsorption of heavy metal through polymeric nano adsorbents is the emerging technology which is more efficient than conventional adsorbents like activated carbon. The pH 9.0 gave maximum 96% sorption of Co at 1.0 g/L adsorbent dosage, due to increased electrostatic force of attraction produced by the negative charge at the surface of sorbent which is favorable for adsorbing cationic species. In the beginning of15 minute retention time, metal ions adsorption was rapid due to availability of more number of adsorptive sites but further increase of retention time decreased the sorption capacity due to partial desorption that may occur due to the charge density and diameter of hydrated ions. Similarly in case of Cu, the...
The magnetic property in a material is induced by the unpaired electrons. This can occur due to d... more The magnetic property in a material is induced by the unpaired electrons. This can occur due to defect states which can enhance the magnetic moment and the spin polarization. In this report, CdS and CdTe thin films are grown on FTO glass substrates by chemical bath deposition and close-spaced sublimation, respectively. The magnetic properties, which are introduced from oxygen states, are found in CdS and CdTe thin films. From the hysteresis loop of magnetic moment it is revealed that CdS and CdTe thin films have different kinds of magnetic moments at different temperatures. The M–H curves indicate that from 100 K to 350 K, CdS and CdTe thin films show paramagnetism and diamagnetism, respectively. A superparamagnetic or a weakly ferromagnetic response is found at 5 K. It is also observed from ZFC/FC curves that magnetic moments decrease with temperature increasing. Spin polarized density functional calculation for spin magnetic moment is also carried out.
Langmuir : the ACS journal of surfaces and colloids, May 10, 2017
We demonstrate a hetero-structure Ni9S8/MoS2 hybrid with tight interface synthesized via an impro... more We demonstrate a hetero-structure Ni9S8/MoS2 hybrid with tight interface synthesized via an improved hydrothermal method. As compared to pure MoS2, the increased surface area and the shorten charge transport pathway in the layered hybrid significantly promote the photocatalytic efficiency for hydrogen evolution reaction (HER). In particularly, the optimized Ni9S8/MoS2 hybrid with 20 wt% Ni9S8 exhibits the highest photocatalytic activity with HER value of 406 μmolg-1h-1, which is enhanced by 70% compared to that of pure MoS2 nanosheets (285.0 μmolg-1h-1). Moreover, the value is 4 times more than the commercial MoS2 (92.0 μmolg-1h-1), indicating the high potential of the hybrid in the catalytic fields.
Uploads
Papers by Hafiz Masood