Publications by authors named "V Divakar Botcha"

The wafer-scale single-crystal GaN film was transferred from a commercial bulk GaN wafer onto a Si (100) substrate by combining ion-cut and surface-activated bonding. Well-defined, uniformly thick, and large-scale wafer size ReS multilayers were grown on the GaN substrate. Finally, ReS photodetectors were fabricated on GaN and sapphire substrates, respectively, and their performances were compared.

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Two-dimensional layered materials have attracted tremendous attention as photodetectors due to their fascinating features, including comprehensive coverage of band gaps, high potential in new-generation electronic devices, mechanical flexibility, and sensitive light-mass interaction. Currently, graphene and transition-metal dichalcogenides (TMDCs) are the most attractive active materials for constructing photodetectors. A growing number of emerging TMDCs applied in photodetectors bring up opportunities in the direct band gap independence with thickness.

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Article Synopsis
  • The study investigates the creation of reduced graphene oxide-zinc oxide (rGO-ZnO) nanocomposites using rapid thermal treatment, focusing on the effects of zinc ion absorption and heat on their properties.
  • Techniques like atomic force microscopy and HR-TEM reveal that the surface features of the composites depend more on treatment temperature rather than zinc concentration, leading to properties including zinc carboxylate presence and formation of ZnO nanoparticles.
  • Optical tests show the rGO-ZnO composites have about 87% transmittance, and photocatalytic experiments indicate they can effectively degrade methylene blue under UV light without clumping.
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Langmuir-Blodgett monolayer sheets of graphene oxide (GO) were transferred onto Si and SiO2/Si, and subjected to hydrogen plasma treatment near room temperature. GO monolayers were morphologically stable at low power (15 W) plasma treatment, for durations up to 2 min and temperatures up to 120 °C. GO monolayers reduced under optimized plasma treatment conditions (30 s duration at 50 °C) exhibit a sheet thickness of (0.

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Large area GO-Cd composite Langmuir-Blodgett monolayers were transferred onto Si substrate by introducing Cd(2+) ions into the subphase. The changes in the behaviour of the Langmuir monolayer isotherm in the presence of Cd(2+) ions are attributed to changes in the microstructure and density of the GO sheets on the subphase surface. The uptake of Cd onto the GO monolayers and the effect of subsequent sulphidation were investigated by AFM, FTIR, Raman, XPS and HRTEM techniques.

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