The field of III-nitride (InGaN) nanowire micro light-emitting diode (µ-LED) displays is rapidly ... more The field of III-nitride (InGaN) nanowire micro light-emitting diode (µ-LED) displays is rapidly expanding and holds great promise, thanks to their chemical stability and outstanding performance across the entire visible spectrum. Notably, III-nitride (InGaN) nanowires, free from compositional substitutions, dislocations, and piezoelectric polarization effects associated with lateral strain relaxation with large surface-to-bulk-volume ratio, are advantage-missing in traditional planar counterparts. This comprehensive overview examines the potential landscape, associated challenges, strategies to overcome them, and opportunities for the development of advanced µ-LED displays with vibrant and accurate color representation, contributing to the advancement of next-generation display technologies. This study also covers the current obstacles faced by III-nitride (InGaN) nanowire-µ-LED displays and possible solutions to address them.
• Facile synthesis of graphene na-nosheets-manganese sulfide (GNS-MnS) hybrid nanocomposite by a ... more • Facile synthesis of graphene na-nosheets-manganese sulfide (GNS-MnS) hybrid nanocomposite by a simple hydrothermal method. • GNS-MnS hybrid nanocomposite exhibited a maximum specific capaci-tance of 792 F g −1 at 2 A g −1 than the pristine MnS. • GNS-MnS hybrid nanocomposite symmetric cell delivered a high energy density of 25 W h kg −1 and power density of 7.16 kW kg −1. • The symmetric cell showed ∼91% electrochemical stability for 15,000 cycles. A B S T R A C T With high power density and promising possibilities for high energy density, the electrochemical capacitor has become an indispensable energy storage device to satisfy the future energy demands. Here in, we report on synthesis of graphene nanosheets (GNS) supported manganese sulfide (MnS) hybrid (GNS-MnS) nanocomposite by a simple, facile hydrothermal process. The resultant GNS-MnS hybrid nanocomposite with robust electronic amalgamation facilitates swift transfer of both ions and electrons across the interface between electrode surface and electrolyte ions than pristine MnS. Benefiting from the better conduction along with improved active sites of the MnS in GNS-MnS hybrid nanocomposite, a high ratio surface/near-surface reactions is dominated by high specific capacity even at high current rate. As such, the GNS-MnS hybrid nanocomposite exhibited a maximum specific capacitance of 792 F g −1 at 2 A g −1 along with better retention rate of 58% at 15 A g −1 , is significantly higher than that of pristine MnS (423 F g −1 at 2 A g −1 and 37% retention at 15 A g −1). In addition, the fabricated symmetric GNS-MnS hybrid nanocomposite cell delivered a high energy density of 25 W h kg −1 and power density of 7160 W kg −1. Moreover, specific capacitance of 91.1% is retained after 15000 th cycles with columbic efficiency of ∼100% at 20 A g −1. The remarkable electrochemical performance of GNS-MnS hybrid nano-composite electrode demonstrated its potential as a key material for developing high energy supercapacitors.
A B S T R A C T We report on a simple and facile synthesis of manganese ferrite (MnFe 2 O 4) nano... more A B S T R A C T We report on a simple and facile synthesis of manganese ferrite (MnFe 2 O 4) nanoparticles by chemical co-precipitation method using 1 M NaOH as the oxidative solution. The resultant nanoparticles were characterized by using various tools like powder X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. The morphology of the resultant product was observed to be of spherical in shape with diameter of about 20–50 nm. The electrochemical performance of manganese ferrite nanoparticles was investigated by using cyclic voltammetry, charge–discharge and electrochemical impedance spectroscopy with different electrolytes, such as 1 M LiNO 3 , 1 M Li 3 PO 4 and KOH. In a three-electrode system, a maximum specific capacitance of 173, 31 and 430 F g −1 was attained corresponding to the electrolytes of 3.5 M KOH, 1 M LiNO 3 and 1 M Li 3 PO 4 , respectively. Among these, 3.5 M KOH electrolyte medium exhibited excellent rate performance, evidently more than 60% of retention was observed at 10 A g −1 due to the synergistic activities, high surface accessibility and better electronic conductivity of MnFe 2 O 4 nanoparticles. In addition, the fabrication of symmetric cell using MnFe 2 O 4 as an electrode materials with 3.5 M KOH as an electrolyte, exhibited maximum specific capacitance, high energy density and power density of 245 F g −1 , 12.6 Wh kg −1 and 1207 W kg −1 , respectively. Furthermore, the specific capacitance of 105% retained after 10,000 cycles at the high current density of 1.5 A g −1 and the coulombic efficiency of the all 10,000 cycles remains constant (∼98) which clearly displayed
Gallium nitride nanostructures have been receiving considerable attention as building blocks for ... more Gallium nitride nanostructures have been receiving considerable attention as building blocks for nanophotonic technologies due to their unique high aspect ratios, promising the realization of photonic and biological nanodevices such as blue light emitting diodes (LEDs), short-wavelength ultraviolet nanolasers, and nanofluidic biochemical sensors. We report on the growth of hierarchical GaN nanowires (NWs) by dynamically adjusting the growth parameters using the pulsed flow metal-organic chemical vapor deposition technique. We carried out two step growth processes to grow hierarchical GaN NWs. In the first step, the GaN NWs were grown at 950°C, and in the second, we suitably decreased the growth temperature to 630°C and 710°C to grow the hierarchical structures. The surface morphology and optical characterization of the grown GaN NWs were studied by field-emission scanning electron microscopy, high-resolution transmission electron microscopy, photoluminescence, and cathodoluminescence measurements. These kinds of hierarchical GaN NWs are promising for allowing flat band quantum structures that are shown to improve the efficiency of LEDs.
Spherical-like ball-by-ball architecture of Ni-Co-Zn-S was obtained through one pot simple and fa... more Spherical-like ball-by-ball architecture of Ni-Co-Zn-S was obtained through one pot simple and facile hydrothermal method without any surfactant. The as synthesized crystalline powder was characterized by using various tools like powder X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. Furthermore, the electrochemical performance studies were carried out from cyclic-voltammetry (CV), galvanostatic charge–discharge (CD) and electrochemical impedance spectroscopy (EIS), within 3.5 M KOH. The consistent increment of clear redox peaks were obtained from CV characteristics due to synergic activities of Ni, Co and Zn. In addition, the presence of Zn ions into Ni and Co has increased its electronic conductivity; therefore, we could observe the superior performance. Thus, Ni-Co-Zn-S exhibited a maximum specific capacitance of 825, 680, 582, 512, 460, 432, 392 and 328 Fg −1 at 1, 2, 3, 4, 5, 6, 7 and 10 Ag −1 within 3.5 M KOH electrolyte. The obtained results are suggesting the excellent electrochemical activities with affordable rate of Ni-Co-Zn-S which is suitable electrode for device applications. Thus, our results may pave the way for the fabrication of advanced high energy storage device through a low-cost preparation to attain the extraordinary limit in energy device industry.
The field of III-nitride (InGaN) nanowire micro light-emitting diode (µ-LED) displays is rapidly ... more The field of III-nitride (InGaN) nanowire micro light-emitting diode (µ-LED) displays is rapidly expanding and holds great promise, thanks to their chemical stability and outstanding performance across the entire visible spectrum. Notably, III-nitride (InGaN) nanowires, free from compositional substitutions, dislocations, and piezoelectric polarization effects associated with lateral strain relaxation with large surface-to-bulk-volume ratio, are advantage-missing in traditional planar counterparts. This comprehensive overview examines the potential landscape, associated challenges, strategies to overcome them, and opportunities for the development of advanced µ-LED displays with vibrant and accurate color representation, contributing to the advancement of next-generation display technologies. This study also covers the current obstacles faced by III-nitride (InGaN) nanowire-µ-LED displays and possible solutions to address them.
• Facile synthesis of graphene na-nosheets-manganese sulfide (GNS-MnS) hybrid nanocomposite by a ... more • Facile synthesis of graphene na-nosheets-manganese sulfide (GNS-MnS) hybrid nanocomposite by a simple hydrothermal method. • GNS-MnS hybrid nanocomposite exhibited a maximum specific capaci-tance of 792 F g −1 at 2 A g −1 than the pristine MnS. • GNS-MnS hybrid nanocomposite symmetric cell delivered a high energy density of 25 W h kg −1 and power density of 7.16 kW kg −1. • The symmetric cell showed ∼91% electrochemical stability for 15,000 cycles. A B S T R A C T With high power density and promising possibilities for high energy density, the electrochemical capacitor has become an indispensable energy storage device to satisfy the future energy demands. Here in, we report on synthesis of graphene nanosheets (GNS) supported manganese sulfide (MnS) hybrid (GNS-MnS) nanocomposite by a simple, facile hydrothermal process. The resultant GNS-MnS hybrid nanocomposite with robust electronic amalgamation facilitates swift transfer of both ions and electrons across the interface between electrode surface and electrolyte ions than pristine MnS. Benefiting from the better conduction along with improved active sites of the MnS in GNS-MnS hybrid nanocomposite, a high ratio surface/near-surface reactions is dominated by high specific capacity even at high current rate. As such, the GNS-MnS hybrid nanocomposite exhibited a maximum specific capacitance of 792 F g −1 at 2 A g −1 along with better retention rate of 58% at 15 A g −1 , is significantly higher than that of pristine MnS (423 F g −1 at 2 A g −1 and 37% retention at 15 A g −1). In addition, the fabricated symmetric GNS-MnS hybrid nanocomposite cell delivered a high energy density of 25 W h kg −1 and power density of 7160 W kg −1. Moreover, specific capacitance of 91.1% is retained after 15000 th cycles with columbic efficiency of ∼100% at 20 A g −1. The remarkable electrochemical performance of GNS-MnS hybrid nano-composite electrode demonstrated its potential as a key material for developing high energy supercapacitors.
A B S T R A C T We report on a simple and facile synthesis of manganese ferrite (MnFe 2 O 4) nano... more A B S T R A C T We report on a simple and facile synthesis of manganese ferrite (MnFe 2 O 4) nanoparticles by chemical co-precipitation method using 1 M NaOH as the oxidative solution. The resultant nanoparticles were characterized by using various tools like powder X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. The morphology of the resultant product was observed to be of spherical in shape with diameter of about 20–50 nm. The electrochemical performance of manganese ferrite nanoparticles was investigated by using cyclic voltammetry, charge–discharge and electrochemical impedance spectroscopy with different electrolytes, such as 1 M LiNO 3 , 1 M Li 3 PO 4 and KOH. In a three-electrode system, a maximum specific capacitance of 173, 31 and 430 F g −1 was attained corresponding to the electrolytes of 3.5 M KOH, 1 M LiNO 3 and 1 M Li 3 PO 4 , respectively. Among these, 3.5 M KOH electrolyte medium exhibited excellent rate performance, evidently more than 60% of retention was observed at 10 A g −1 due to the synergistic activities, high surface accessibility and better electronic conductivity of MnFe 2 O 4 nanoparticles. In addition, the fabrication of symmetric cell using MnFe 2 O 4 as an electrode materials with 3.5 M KOH as an electrolyte, exhibited maximum specific capacitance, high energy density and power density of 245 F g −1 , 12.6 Wh kg −1 and 1207 W kg −1 , respectively. Furthermore, the specific capacitance of 105% retained after 10,000 cycles at the high current density of 1.5 A g −1 and the coulombic efficiency of the all 10,000 cycles remains constant (∼98) which clearly displayed
Gallium nitride nanostructures have been receiving considerable attention as building blocks for ... more Gallium nitride nanostructures have been receiving considerable attention as building blocks for nanophotonic technologies due to their unique high aspect ratios, promising the realization of photonic and biological nanodevices such as blue light emitting diodes (LEDs), short-wavelength ultraviolet nanolasers, and nanofluidic biochemical sensors. We report on the growth of hierarchical GaN nanowires (NWs) by dynamically adjusting the growth parameters using the pulsed flow metal-organic chemical vapor deposition technique. We carried out two step growth processes to grow hierarchical GaN NWs. In the first step, the GaN NWs were grown at 950°C, and in the second, we suitably decreased the growth temperature to 630°C and 710°C to grow the hierarchical structures. The surface morphology and optical characterization of the grown GaN NWs were studied by field-emission scanning electron microscopy, high-resolution transmission electron microscopy, photoluminescence, and cathodoluminescence measurements. These kinds of hierarchical GaN NWs are promising for allowing flat band quantum structures that are shown to improve the efficiency of LEDs.
Spherical-like ball-by-ball architecture of Ni-Co-Zn-S was obtained through one pot simple and fa... more Spherical-like ball-by-ball architecture of Ni-Co-Zn-S was obtained through one pot simple and facile hydrothermal method without any surfactant. The as synthesized crystalline powder was characterized by using various tools like powder X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. Furthermore, the electrochemical performance studies were carried out from cyclic-voltammetry (CV), galvanostatic charge–discharge (CD) and electrochemical impedance spectroscopy (EIS), within 3.5 M KOH. The consistent increment of clear redox peaks were obtained from CV characteristics due to synergic activities of Ni, Co and Zn. In addition, the presence of Zn ions into Ni and Co has increased its electronic conductivity; therefore, we could observe the superior performance. Thus, Ni-Co-Zn-S exhibited a maximum specific capacitance of 825, 680, 582, 512, 460, 432, 392 and 328 Fg −1 at 1, 2, 3, 4, 5, 6, 7 and 10 Ag −1 within 3.5 M KOH electrolyte. The obtained results are suggesting the excellent electrochemical activities with affordable rate of Ni-Co-Zn-S which is suitable electrode for device applications. Thus, our results may pave the way for the fabrication of advanced high energy storage device through a low-cost preparation to attain the extraordinary limit in energy device industry.
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