Japinder Kaur - Academia.edu (original) (raw)

Papers by Japinder Kaur

Metallography, Microstructure, and Analysis, 2018

This study deals with a facile strategy to coat the surface of reduced activation ferritic/marten... more This study deals with a facile strategy to coat the surface of reduced activation ferritic/martensitic steel (RAFMS) substrate with alumina and aluminide layer. The coating on the surface of the substrate was obtained by using hot dip aluminization technique followed by heat treatment. The thickness, phases, and composition of the coating were analyzed using optical microscopy, XRD, and scanning electron microscopy-EDS studies. Optical microscopy images of the dipped sample revealed the presence of two distinguished layers: an outer thick layer (thickness about 32 µm) and an inner thin layer (thickness about 18 µm). Similarly, optical microscopy images of heat-treated samples indicated the presence of two layers but with increased thickness: outer layer (thickness about 120 µm) and inner layer (thickness about 80 µm). The XRD pattern of dipped sample revealed the presence of Al and Si on the surface of the coating while that of heat-treated sample indicated the presence of Fe 2 Al 5 , α-Al 2 O 3 , and θ-Al 2 O 3. Scanning electron microscopy-EDS studies revealed the presence of three distinct layers in dipped samples: outer layer consisting of Al and Si having thickness 33 µm, middle finger-like layer having thickness 12 µm and inner layer having thickness of 6 µm. Likewise, for heat-treated sample, three layers were observed but with increased thickness.

Nanoparticles of Co 0.5 Zn 0.5 Al x Fe 2− x O 4 ( x = 0, 0.2, 0.4, 0.6, 0.8 and 1.0) were synthe... more Nanoparticles of Co 0.5 Zn 0.5 Al x Fe 2− x O 4 ( x = 0, 0.2, 0.4, 0.6, 0.8 and 1.0) were synthesized by sol–gel method and the influence of Al 3+ doping on the properties of Co 0.5 Zn 0.5 Fe 2 O 4 was studied. X-ray diffraction studies revealed the formation of single phase spinel type cubical structure having space group Fd-3m. A decreasing trend of the lattice parameter was observed with increasing Al 3+ concentration due to the smaller ionic radii of Al 3+ ion as compared to Fe 3+ ion. TEM was used to characterize the microstructure of the samples and particle size determination, which exhibited the formation of spherical nanoparticles. The particle size was found to be increases up to ∼45 nm after annealing the sample at 1000 °C. Electrical resistivity was found to increase with Al 3+ doping, attributed to the decrease in the number of Fe 2+ –Fe 3+ hopping. The activation energy decreased with increasing Al 3+ ion concentration, indicating the blocking of conduction mechanism ...

Materials Chemistry and Physics, 2016

CeO 2 /ZnO nanocomposites were fabricated using hydrothermal method. Photocatalytic efficiency of... more CeO 2 /ZnO nanocomposites were fabricated using hydrothermal method. Photocatalytic efficiency of CeO 2 /ZnO nanocomposites was compared with their monocomponent counterparts. Experimental conditions were optimized for the degradation of methylene blue dye. CeO 2 /ZnO nanocomposite proved to be a better candidate for the photocatalytic degradation of dye.

Ceramics International, 2016

Abstract Highly efficient photocatalytic Ag-decorated ZnO nanopowders were fabricated via photode... more Abstract Highly efficient photocatalytic Ag-decorated ZnO nanopowders were fabricated via photodeposition method. The physical properties of synthesized nanopowders were rigorously investigated using analytical techniques, such as, powder XRD studies, HR-TEM and PL spectroscopy. The surface area of samples was obtained using BET analysis. The potential of synthesized nanopowders as photocatalyst was evaluated by studying the degradation of basonyl violet dye. Coating of ZnO nanopowders with metallic silver resulted in a remarkable improvement in photocatalytic activity. Moreover, most proficient conditions were deduced for the degradation of basonyl violet, by varying parameters, such as, catalyst loading, concentration of dye, and solution pH, using Ag-decorated ZnO nanopowders under UV irradiation.

Journal of Chemical Technology & Biotechnology, 2015

BACKGROUND: Due to urbanization, the release of coloured wastewaters from textile industries into... more BACKGROUND: Due to urbanization, the release of coloured wastewaters from textile industries into various environmental components has increased and is posing a threat to water bodies, so that their eradication from water bodies is necessary. To this end, semiconductor heterogeneous photocatalysis has emerged as a promising tool. However, as is well known, photocatalysis is a surface phenomenon; therefore it is strongly influenced by the fabrication technique employed for its synthesis. To address this issue, the present work demonstrates the dependence of synthetic methodology on photocatalytic efficacy of ZnO catalyst. RESULTS: Catalytically active nanostructured ZnO particles were fabricated by five different facile methodologies. The fabricated nanostructures were critically analysed using techniques such as, X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM), Brunauer-Emmett-Teller (BET) and photoluminescence (PL) spectrophotometer. The photocatalytic activity of different ZnO catalysts was compared by using safranin O dye as probe molecule. CONCLUSIONS: ZnO nanopowders fabricated by different methodologies were found to display different catalytic efficiencies, which was ascribed to large variations in specific surface area and rate of recombination of electrons and holes. Therefore, it is perceived that ZnO catalyst with best catalytic activity can be utilized to streamline the treatment of dye wastewater and is an ideal catalyst for a practical approach.

Physica B: Condensed Matter, 2014

Thephotodegradatlon has been studled of the catlomc surfactant N-dodecylpyndmum cblorlde (N-DPCl)... more Thephotodegradatlon has been studled of the catlomc surfactant N-dodecylpyndmum cblorlde (N-DPCl) m aqueous heterogeneous dsperslons of semlconductmg catalyst particles (TIOZ, T102/ Pt and ZnO) The photooxldatlon was followed by UV spectrophotometry and surface tenslon measurements The photodegradatlon approximates first order kinetics and 1s discussed on the basis of a simple phenomenolo@cal mode1 The degradation rate 1s almost identical for T102 and ZnO and higher than that for TlO*/Pt A high mmerahzatlon yield 1s obtained from measurements of CO, evolution, while an increase m the surface tension 19 observed Pyndmum nng breakage, which 1s known to proceed mth difficulty, 1s also indicated by the presence of NH: and NO; ions

Physica B: Condensed Matter, 2012

Pure and Cu doped ZnO nanopowders (5, 10, 15, 20, 25 and 30at% Cu) have been synthesized using co... more Pure and Cu doped ZnO nanopowders (5, 10, 15, 20, 25 and 30at% Cu) have been synthesized using co-precipitation method. Transmission Electron Microscopic analysis has shown the morphology of ZnO nanopowders to be quasi-spherical. Powder X-ray ...

Ceramics International, 2014

ABSTRACT

Superlattices and Microstructures, 2015

In present work, highly efficient photocatalytic ZnO nanoparticles have been successfully synthes... more In present work, highly efficient photocatalytic ZnO nanoparticles have been successfully synthesized by a facile method involving thermal decomposition of oxalate precursor. The synthesized nanoparticles were rigorously characterized via analytical techniques such as XRD, HR-TEM, SAED, STEM, EDS, UV-vis spectroscopy and BET analysis. The synthesized nanoparticles were utilized for the eradication of eriochrome black T dye. Complete degradation of dye was observed in 90 min. The most favorable results were observed at catalyst loading 1 g/L in acidic region. The presence of hydroxyl radicals in the photocatalytic reaction mixture was also established. Degradation of effluent from a textile industry was also investigated, and ZnO was found to be a promising candidate for their degradation.

Ceramics International, 2012

ABSTRACT

Metallography, Microstructure, and Analysis, 2018

This study deals with a facile strategy to coat the surface of reduced activation ferritic/marten... more This study deals with a facile strategy to coat the surface of reduced activation ferritic/martensitic steel (RAFMS) substrate with alumina and aluminide layer. The coating on the surface of the substrate was obtained by using hot dip aluminization technique followed by heat treatment. The thickness, phases, and composition of the coating were analyzed using optical microscopy, XRD, and scanning electron microscopy-EDS studies. Optical microscopy images of the dipped sample revealed the presence of two distinguished layers: an outer thick layer (thickness about 32 µm) and an inner thin layer (thickness about 18 µm). Similarly, optical microscopy images of heat-treated samples indicated the presence of two layers but with increased thickness: outer layer (thickness about 120 µm) and inner layer (thickness about 80 µm). The XRD pattern of dipped sample revealed the presence of Al and Si on the surface of the coating while that of heat-treated sample indicated the presence of Fe 2 Al 5 , α-Al 2 O 3 , and θ-Al 2 O 3. Scanning electron microscopy-EDS studies revealed the presence of three distinct layers in dipped samples: outer layer consisting of Al and Si having thickness 33 µm, middle finger-like layer having thickness 12 µm and inner layer having thickness of 6 µm. Likewise, for heat-treated sample, three layers were observed but with increased thickness.

Nanoparticles of Co 0.5 Zn 0.5 Al x Fe 2− x O 4 ( x = 0, 0.2, 0.4, 0.6, 0.8 and 1.0) were synthe... more Nanoparticles of Co 0.5 Zn 0.5 Al x Fe 2− x O 4 ( x = 0, 0.2, 0.4, 0.6, 0.8 and 1.0) were synthesized by sol–gel method and the influence of Al 3+ doping on the properties of Co 0.5 Zn 0.5 Fe 2 O 4 was studied. X-ray diffraction studies revealed the formation of single phase spinel type cubical structure having space group Fd-3m. A decreasing trend of the lattice parameter was observed with increasing Al 3+ concentration due to the smaller ionic radii of Al 3+ ion as compared to Fe 3+ ion. TEM was used to characterize the microstructure of the samples and particle size determination, which exhibited the formation of spherical nanoparticles. The particle size was found to be increases up to ∼45 nm after annealing the sample at 1000 °C. Electrical resistivity was found to increase with Al 3+ doping, attributed to the decrease in the number of Fe 2+ –Fe 3+ hopping. The activation energy decreased with increasing Al 3+ ion concentration, indicating the blocking of conduction mechanism ...

Materials Chemistry and Physics, 2016

CeO 2 /ZnO nanocomposites were fabricated using hydrothermal method. Photocatalytic efficiency of... more CeO 2 /ZnO nanocomposites were fabricated using hydrothermal method. Photocatalytic efficiency of CeO 2 /ZnO nanocomposites was compared with their monocomponent counterparts. Experimental conditions were optimized for the degradation of methylene blue dye. CeO 2 /ZnO nanocomposite proved to be a better candidate for the photocatalytic degradation of dye.

Ceramics International, 2016

Abstract Highly efficient photocatalytic Ag-decorated ZnO nanopowders were fabricated via photode... more Abstract Highly efficient photocatalytic Ag-decorated ZnO nanopowders were fabricated via photodeposition method. The physical properties of synthesized nanopowders were rigorously investigated using analytical techniques, such as, powder XRD studies, HR-TEM and PL spectroscopy. The surface area of samples was obtained using BET analysis. The potential of synthesized nanopowders as photocatalyst was evaluated by studying the degradation of basonyl violet dye. Coating of ZnO nanopowders with metallic silver resulted in a remarkable improvement in photocatalytic activity. Moreover, most proficient conditions were deduced for the degradation of basonyl violet, by varying parameters, such as, catalyst loading, concentration of dye, and solution pH, using Ag-decorated ZnO nanopowders under UV irradiation.

Journal of Chemical Technology & Biotechnology, 2015

BACKGROUND: Due to urbanization, the release of coloured wastewaters from textile industries into... more BACKGROUND: Due to urbanization, the release of coloured wastewaters from textile industries into various environmental components has increased and is posing a threat to water bodies, so that their eradication from water bodies is necessary. To this end, semiconductor heterogeneous photocatalysis has emerged as a promising tool. However, as is well known, photocatalysis is a surface phenomenon; therefore it is strongly influenced by the fabrication technique employed for its synthesis. To address this issue, the present work demonstrates the dependence of synthetic methodology on photocatalytic efficacy of ZnO catalyst. RESULTS: Catalytically active nanostructured ZnO particles were fabricated by five different facile methodologies. The fabricated nanostructures were critically analysed using techniques such as, X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM), Brunauer-Emmett-Teller (BET) and photoluminescence (PL) spectrophotometer. The photocatalytic activity of different ZnO catalysts was compared by using safranin O dye as probe molecule. CONCLUSIONS: ZnO nanopowders fabricated by different methodologies were found to display different catalytic efficiencies, which was ascribed to large variations in specific surface area and rate of recombination of electrons and holes. Therefore, it is perceived that ZnO catalyst with best catalytic activity can be utilized to streamline the treatment of dye wastewater and is an ideal catalyst for a practical approach.

Physica B: Condensed Matter, 2014

Thephotodegradatlon has been studled of the catlomc surfactant N-dodecylpyndmum cblorlde (N-DPCl)... more Thephotodegradatlon has been studled of the catlomc surfactant N-dodecylpyndmum cblorlde (N-DPCl) m aqueous heterogeneous dsperslons of semlconductmg catalyst particles (TIOZ, T102/ Pt and ZnO) The photooxldatlon was followed by UV spectrophotometry and surface tenslon measurements The photodegradatlon approximates first order kinetics and 1s discussed on the basis of a simple phenomenolo@cal mode1 The degradation rate 1s almost identical for T102 and ZnO and higher than that for TlO*/Pt A high mmerahzatlon yield 1s obtained from measurements of CO, evolution, while an increase m the surface tension 19 observed Pyndmum nng breakage, which 1s known to proceed mth difficulty, 1s also indicated by the presence of NH: and NO; ions

Physica B: Condensed Matter, 2012

Pure and Cu doped ZnO nanopowders (5, 10, 15, 20, 25 and 30at% Cu) have been synthesized using co... more Pure and Cu doped ZnO nanopowders (5, 10, 15, 20, 25 and 30at% Cu) have been synthesized using co-precipitation method. Transmission Electron Microscopic analysis has shown the morphology of ZnO nanopowders to be quasi-spherical. Powder X-ray ...

Ceramics International, 2014

ABSTRACT

Superlattices and Microstructures, 2015

In present work, highly efficient photocatalytic ZnO nanoparticles have been successfully synthes... more In present work, highly efficient photocatalytic ZnO nanoparticles have been successfully synthesized by a facile method involving thermal decomposition of oxalate precursor. The synthesized nanoparticles were rigorously characterized via analytical techniques such as XRD, HR-TEM, SAED, STEM, EDS, UV-vis spectroscopy and BET analysis. The synthesized nanoparticles were utilized for the eradication of eriochrome black T dye. Complete degradation of dye was observed in 90 min. The most favorable results were observed at catalyst loading 1 g/L in acidic region. The presence of hydroxyl radicals in the photocatalytic reaction mixture was also established. Degradation of effluent from a textile industry was also investigated, and ZnO was found to be a promising candidate for their degradation.

Ceramics International, 2012

ABSTRACT