InGaN/GaN multi-quantum well nanowires: Enhanced trace-level NO2 detection for environmental and breath analysis

초록

The World Health Organization highlights nitrogen dioxide (NO<inf>2</inf>) as a key atmospheric pollutant impacting air quality and human health. To date, several sensors have been proposed for NO<inf>2</inf> detection and disease monitoring, but their effectiveness is limited because of low sensitivity and high operational temperatures. Herein, we propose a selective and sensitive NO<inf>2</inf> sensor based on indium gallium nitride/gallium nitride multiple quantum wells (InGaN/GaN-MQWs). We explored different InGaN/GaN-MQWs configurations (InGaN/GaN-MQW<inf>1</inf>, InGaN/GaN-MQW<inf>2</inf>, InGaN/GaN-MQW<inf>3</inf>), developed through metal–organic chemical vapor deposition (MOCVD), to analyze their impact on gas sensing performance. Our findings reveal that the InGaN/GaN-MQW<inf>2</inf> sensor at 150 °C exhibits a response 4.0, 3.1, and 1.65 times greater than GaN-NWs, InGaN/GaN-MQW<inf>1</inf>, and InGaN/GaN-MQW<inf>3</inf> sensors, respectively. The limit of detection (LOD) for the InGaN/GaN-MQW<inf>2</inf> sensor is 3 parts per billion (ppb), significantly lower than the NO<inf>2</inf> threshold value of 53 ppb. Under ultraviolet (UV) light, the response of InGaN/GaN-MQW<inf>2</inf> is 5.51-fold, 4.18-fold, and 1.82-fold higher than that of the GaN-NWs, InGaN/GaN-MQW<inf>1</inf>, and InGaN/GaN-MQW<inf>2</inf> sensors, respectively. Importantly, our hybrid nanocomposite-based electronic nose (e-nose) sensor arrays could distinguish between healthy and simulated unhealthy breaths with high accuracy, promising a new era of efficient, non-invasive disease detection through breath analysis. © 2024

키워드