Visible light assisted trace gaseous NO2 sensor with anti-humidity ability via LSPR enhancement effect

Transition metal dichalcogenides (TMDs) have been received widespread attention for NO 2 detection at room temperature . However, the TMDs-based gas sensors usually possess inferior response capability and suffer from humidity interference due to lack of sufficient reaction activation energy , which seems tough to achieve the detection of ppb-level gases and hinder the practical applications. Herein, we propose a visible light-assisted-type gas sensor based on Au-decorated WS 2 , endowing high-performance detection of NO 2 at room temperature. Benefited from the localized surface plasmon resonance (LSPR) enhancement effect induced by the modified Au nanoparticles (NPs), the visible light-assisted Au/WS 2 gas sensor can implement the detection of NO 2 gas as low as 20 ppb. Moreover, the maximum drift of the sensor response value is only 3% in the range of 10%−90% RH, indicating the stabilized anti-humidity ability. The effective regulation of transmission channel by the modified noble metal and the enhancement of visible light absorption of WS 2 through taking full advantage of the LSPR effect are the main reasons for realizing low concentration detection and improving the anti-humidity ability. Therefore, the visible light-assisted gas detection mode can serve as a proof-of-concept to provide an effective approach for the detection of trace gases at room temperature.