H2S sensing under various humidity conditions with Ag nanoparticle functionalized Ti3C2Tx MXene field-effect transistors

Despite the critical need to monitor H2S, a hazardous gas, in environmental and medical settings, there are currently no reliable methods for rapid and sufficiently discriminative H2S detection in real-world humid environments. Herein, targeted hybridizing of Ti3C2Tx MXene with Ag nanoparticles on a field-effect transistor (FET) platform has led to a step change in MXene sensing performance down to ppb levels, and enabled the very high selectivity and fast response/recovery time under room temperature for H2S detection in humid conditions. For the first time, we present a novel relative humidity (RH) self-calibration strategy for the accurate detection of H2S. This strategy can eliminate the influence of humidity and enables the accurate quantitative detection of gas in the total RH range. We further elucidate that the superior H2S sensing performance is attributed to the electron and chemical sensitization effects. This study opens new avenues for the development of high-performance MXene-based sensors and offers a viable approach for addressing real-world humidity effect for gas sensors generally.