Enhanced Photodetection Performance of WSe2/V2O5 Nanocomposite on Flexible Substrate: Synergistic Advantages and Improved Efficiency

The two-dimensional (2D) chalcogenide WSe2/V2O5 composite nanostructures were synthesized using the hydrothermal method and extensively characterized with various spectroscopic techniques. X-ray diffraction analysis confirmed the hexagonal crystal structure exhibiting space symmetry of P6(3)/mmc. Scanning electron microscopy images provided insights into the irregular and nonuniform morphology. Optical spectrum analysis indicated a band gap value of 2.01 eV for 15% WSe2/V2O5 nanostructures, as determined by the Wood and Tauc equation. Photoluminescence (PL) excitation spectra at emission wavelengths of 550 and 750 nm exhibited broad emission attributed to self-trapped excitons for V2O5 and WSe2 nanostructures. Under excitation at lambda(exc) = 365 nm, PL emission spectra displayed distinct peaks at 550 and 750 nm, demonstrating the ability to emit vivid red light. A device optimized for photoresponsivity (R) of approximately 7.80 x 10(-1) A W-1 and detectivity (D) of around 8.65 x 10(11) Jones, and quantum efficiency of approximately 3.42 x 10(-2) A W-1 were achieved at a wavelength of 390 nm while using a lamination sheet as a substrate. These findings underscore the capability of devices for efficient photoconversion at specified wavelengths, indicating potential applications in sensing, imaging, and optical communication. The photoresponsivity of the device remained stable at 3.38 x 10(-3) A W-1 at 0 degrees and 3.09 x 10(-3) A W-1 at 55 degrees bending angle. This indicates the resilience of device to mechanical strain, making it ideal for flexible and wearable sensor applications. The structural, morphological, and optical characterizations confirm the suitability of luminescent WSe2/V2O5 chalcogenide for practical optoelectronic applications, especially in display technologies.