One-step synthesis of Pt-CNTs/rGO electrocatalyst for wearable methanol sensing: Effect of supports on gas-sensitive property

Abstract

Methanol is widely used in the chemical industry to develop downstream products. However, given the toxicity of methanol, it is of huge engineering significance to establish a wearable methanol sensor with a real-time monitoring function. Herein, we have constructed Pt-CNTs/rGO electrocatalysts based wearable sensor with good methanol-sensitive response, including a wide linear detection range, good repeatability, stability, selectivity as well as detectability in real samples. Noteworthy, in this work, CNTs and rGO acted as composite support for loading Pt nanoparticles, electrochemical measurement revealed that the sensing performance of Pt-CNTs/rGO based sensor was better than the sensor used Pt-CNTs due to the synergistic effect of composites support. Density functional theory (DFT) calculations have also demonstrated that rGO was more favorable for the adsorption of methanol molecules than CNTs. When the ratio of CNTs and rGO was 1:2, the methanol sensor exhibited the highest sensitivity and response/recovery speed (less than 12 s for detection of methanol gasoline) compared to that of other proportions. This work provides convincing support for developing wearable electrochemical gas sensors from the point of view of designing electrocatalysts, showing great prospects in the safety detection application, such as early trace gas leak detection and daily monitoring of workers on the shop floor.