Carbon modification endows WO3 with anti-humidity property and long-term stability for ultrafast H2S detection

Abstract

Sensitive and selective determination of H2S has been widely reported. However, its gas sensing performance is vulnerable to some special environments such as high humidity. Especially, the sluggish response/recovery time and the unfavorable long-term stability are the main obstacles for H2S gas sensing. Herein, carbon modification on coral-like WO3 with bimodal pore distribution (mesopores and macropores) has been fabricated by one-step solvothermal method. Experimental results confirm that the coral-like carbon modified WO3 based sensor has excellent H2S sensing performance regarding its rapid response /recovery time (1 s/20 s) to 50 ppm H2S at 275 °C and the low detection limitation at ppb level. In addition, the anti-humidity property and long-term stability are improved through carbon modification. Overall, the results demonstrate that carbon modification on WO3 material and facile synthesis method might provide a potential platform for real-time and practical diagnosis of halitosis.