Rationally Engineered Vertically Aligned β‐Ga_2−xW_xO₃ Nanocomposites for Self‐Biased Solar‐Blind Ultraviolet Photodetectors with Ultrafast Response

Abstract

With the astonishing advancement of present technology and increasing energy consumption, there is an ever‐increasing demand for energy‐efficient multifunctional sensors or transducers based on low‐cost, eco‐friendly material systems. In this context, self‐assembled vertically aligned β‐Ga2−xWxO3 nanocomposite (GWO‐VAN) architecture‐assisted self‐biased solar‐blind UV photodetection on a silicon platform, which is the heart of traditional electronics is presented. Utilizing precisely controlled growth parameters, the formation of W‐enriched vertical β‐Ga2−xWxO3 nanocolumns embedded into the W‐deficient β‐Ga2−xWxO3 matrix is reached. Detailed structural and morphological analyses evidently confirm the presence of β‐Ga2−xWxO3 nanocomposite with a high structural and chemical quality. Furthermore, absorption and photoluminescence spectroscopy explains photo‐absorption dynamics and the recombination through possible donor–acceptor energy states. The proposed GWO‐VAN framework facilitates evenly dispersed nanoregions with asymmetric donor energy state distribution and thus forms build‐in potential at the vertical β‐Ga2−xWxO3 interfaces. As a result, the overall heterostructure evinces photovoltaic nature under the UV irradiation. A responsivity of ≈30 A/W is observed with an ultrafast response time (≈350 µs) under transient triggering conditions. Corresponding detectivity and external quantum efficiency are 7.9 × 1012 Jones and 1.4 × 104%, respectively. It is believed that, while this is the first report exploiting GWO‐VAN architecture to manifest self‐biased solar‐blind UV photodetection, the implication of the approach is enormous in designing electronics for extreme environment functionality and has immense potential to demonstrate drastic improvement in low‐cost UV photodetector technology.

α-Quartz Phase Stabilization, Surface Texturing, and Tunable Optical Properties of Nanocrystalline GeO2 Films Made by Pulsed-Laser Deposition: Implications for Optical and Optoelectronic Applications

“…The specifics of the XPS measurements and analytical methods are provided here for the sake of completeness. The detector was positioned normally with regard to the sample surface, and the X-ray source power was adjusted to generate photoelectrons with an output power of 105 W. The pass energy was set at 20 eV for high-resolution scans and 160 eV for survey scans, with a maximum sample analyzed size area of 700 × 300 μm 2 . For survey and high-resolution scans, the step sizes were 0.5 and 0.1 eV, respectively.…”

“…In addition, there is an increasing demand for highly efficient electronic, optoelectronic, and power-electronic devices, which necessitates efficient functional materials that can also persist under extreme operating conditions. [1][2][3][4]7,10 UWBG oxides readily find applications in photo/electrocatalysis, photovoltaics, hydrogen generation, artificial photosynthesis, electro-optic transistors, synaptic devices, supercapacitors, and electro-chemical energy storage devices. 1−12 As a result, the UWBG semiconductors play a significant role in all of the domains of next-generation energy, electronics, and optoelectronics technologies.…”

The Evolution of Solid Oxide Fuel Cell Materials

“…This is a paradigm of the use of VAN nanocomposites as a tool to fix current kinetic limitations of existing electrodes. The VAN architecture is relatively easy to form and leads to prolonged thermal stability and fast oxygen reduction kinetics [25,[136][137][138]. The predicted lattice strain due to doping, (c) the mean and distribution of site volumes around the La (green) and Sr (blue) sites and (d) bond valence mismatch of the ionic positions for the different cation dopants [25].…”

“…This is a paradigm of the use of VAN nanocomposites as a tool to fix current kinetic limitations of existing electrodes. The VAN architecture is relatively easy to form and leads to prolonged thermal stability and fast oxygen reduction kinetics [25,[136][137][138].…”