Ultrafast Detection of ppb-Level NH Gas at Room Temperature Using CuO Nanoparticles Decorated AlN-Based Surface Acoustic Wave Sensor.

Rational design of heterostructure (HS)-based surface acoustic wave (SAW) smart gas sensors for efficient and accurate subppm level ammonia (NH) detection at room temperature (RT) is of great significance in environmental protection and human safety. This study introduced a novel HS composed of an AlN-based SAW resonator and CuO nanoparticles (NPs) as a chemical interface for NH detection at RT (∼26 °C). The structural, morphological, and chemical compositions were detailly investigated, which demonstrates that the CuO/AlN HS was successfully formed via interfacial modulation.

CuO nanostructure-decorated InGaN nanorods for selective HS gas detection.

Establishing a heterostructure is one of the adequate strategies for enhancing device performance and has been explored in sensing, and energy applications. In this study, we constructed a heterostructure through a two-step process involving hydrothermal synthesis of CuO nanostructures and subsequent spin coating on MBE-grown InGaN NRs. We found that the CuO content on the InGaN NRs has a great impact on carrier injection at the heterojunction and thus the HS gas sensing performance.

Integration of Ag Plasmonic Metal and WO/InGaN Heterostructure for Photoelectrochemical Water Splitting.

In this study, a Ag/WO/InGaN hybrid heterostructure was successfully developed by sputtering and molecular beam epitaxy techniques, to obtain unique Ag nanospheres adorned with cauliflower-like WO nanostructure over the InGaN nanorods (NRs). Exploiting the localized surface plasmon resonance of Ag, the Ag/WO/InGaN heterostructure exhibited superior photoabsorption ability in the visible region (400-700 nm) of the solar spectrum, with a surface plasmon resonance band centered around 440 nm. Comprehensive analysis through photoluminescence spectroscopy, photocurrent measurements, and electrochemical impedance spectroscopy revealed that the Ag/WO/InGaN hybrid heterostructure significantly enhances the charge carrier separation and transfer kinetics leading to improved overall photoelectrochemical (PEC) performance.

High performance langasite based SAW NO gas sensor using 2D g-CN@TiO hybrid nanocomposite.

Nitrogen dioxide (NO) gas has emerged as a severe air pollutant that causes damages to the environment, human life and global ecosystems etc. However, the currently available NO gas sensors suffers from insufficient selectivity, sensitivity and long response times that impeding their practical applicability for room temperature (RT) gas sensing. Herein, we report a high performance langasite (LGS) based surface acoustic wave (SAW) RT NO gas sensor using 2-dimensional (2D) g-CN@TiO nanoplates (NP) with {001} facets hybrid nanocomposite as a chemical interface.

Proliferation of the Light and Gas Interaction with GaN Nanorods Grown on a V-Grooved Si(111) Substrate for UV Photodetector and NO Gas Sensor Applications.

Although excellent milestones of III-nitrides in optoelectronic devices have been achieved, the focus on the optimization of their geometrical structure for multiple applications is very rare. To address this issue, we exclusively designed a prototype device to enhance the photoconversion efficiency and gas interaction capabilities of GaN nanorods (NRs) grown on a V-grooved Si(100) substrate with Si(111) facets for photodetector and gas sensor applications. Photoluminescence studies have demonstrated an increased surface-to-volume ratio and light trapping for GaN NRs grown on V-grooved Si(111).