Electronic and electrocatalytic applications based on solution‐processed two‐dimensional platinum diselenide with thickness‐dependent electronic properties

Abstract Platinum diselenide (PtSe 2 ) has shown great potential as a candidate two‐dimensional (2D) material for broadband photodetectors and electrocatalysts because of its unique properties compared to conventional 2D transition metal dichalcogenides. Synthesis of 2D PtSe 2 with controlled layer number is critical for engineering the electronic behavior to be semiconducting or semimetallic for targeted applications. Electrochemical exfoliation has been investigated as a promising approach for mass‐producing in a cost‐effective manner, but obtaining high‐quality films with control over electronic properties remains difficult. Here, we demonstrate wafer‐scale 2D PtSe 2 films with pre‐determined electronic types based on a facile solution‐based strategy. Semiconducting or semimetallic PtSe 2 nanosheets with large lateral sizes are produced via electrochemically driven molecular intercalation, followed by centrifugation‐based thickness sorting. Finally, gate‐tunable broadband visible and near‐infrared photodetector arrays are realized based on semiconducting PtSe 2 nanosheet films, while semimetallic films are used to create catalytic electrodes for overall water splitting with long‐term stability. image