Extending the Colloidal Transition Metal Dichalcogenide Library to ReS_2 Nanosheets for Application in Gas Sensing and Electrocatalysis

摘要

Among the large family of transition metal dichalcogenides, recently ReS_2 has stood out due to its nearly layer-independent optoelectronic and physicochemical properties related to its 1T distorted octahedral structure. This structure leads to strong in-plane anisotropy, and the presence of active sites at its surface makes ReS_2 interesting for gas sensing and catalysts applications. However, current fabrication methods use chemical or physical vapor deposition (CVD or PVD) processes that are costly, time-consuming and complex, therefore limiting its large-scale production and exploitation. To address this issue, a colloidal synthesis approach is developed, which allows the production of ReS_2 at temperatures below 360 °C and with reaction times shorter than 2h. By combining the solution-based synthesis with surface functionalization strategies, the feasibility of colloidal ReS_2 nanosheet films for sensing different gases is demonstrated with highly competitive performance in comparison with devices built with CVD-grown ReS_2 and MoS_2. In addition, the integration of the ReS_2 nanosheet films in assemblies together with carbon nanotubes allows to fabricate electrodes for electrocatalysis for H_2 production in both acid and alkaline conditions. Results from proof-of-principle devices show an electrocatalytic overpotential competitive with devices based on ReS_2 produced by CVD, and even with MoS_2, WS_2, and MoSe_2 electrocatalysts.