Search

The currently strategies for activating the TMDC basal planes toward hydrogen evolution reaction were summarized, which are divided into internal and external regulation, depending on whether the pristine structure is altered or not.

Single-atom catalysts (SACs) with a maximum atom utilization efficiency have received growing attention in heterogeneous catalysis. The supporting substrate that provides atomic-dispersed anchoring sites and the local electronic environment in these catalysts is crucial to their activity and stability. Here, inspired by N-doped graphene substrate, the role of N is explored in transition metal nitrides for anchoring single metal atoms toward single-atom catalysis. A pore-rich metallic vanadium nitride (VN) nanosheet is fabricated as one supporting-substrate example, whose surface features abundant unsaturated N sites with lower binding energy than that of widely used N-doped graphene. Impressively, it is found that this support can anchor nearly all platinum-group single atoms (e.g., platinum, palladium, iridium, and ruthenium), and even be extendable to multiple SACs, i.e., binary (Pt/Pd) and ternary (Pt/Pd/Ir). As a proof-of-concept application for hydrogen production, Pt-based SAC (Pt

Aqueous supercapacitors had recently received widespread attention due to their eco-safety, cost-efficiency, environmental friendliness, and ease of handling. However, being limited by the voltage of decomposition of water, the operating voltage of aqueous supercapacitors is usually 2 V, which mostly impedes the improvement of energy density (E = 0.5 CV2). In the present study, we illustrate that a VN nanowires@carbon cloth (VN-NWs@CC) electrode possesses a wide potential stability window of −1.4–0.7 V in a high concentration “water in salt” aqueous electrolyte, which can be attributed to the redox reactions occurring at low potentials, delaying the process of hydrogen evolution reaction (HER). Furthermore, the asymmetric supercapacitor, based on a VN-NWs@CC negative electrode and MnO2 nanosheet positive electrode, can obtain a high operating voltage of 3 V. Moreover, the 3 V MnO2@CC//VN-NWs@CC asymmetric supercapacitor exhibits a large energy density of up to 61.5 W h kg−1 with excellent cycling stability, outperforming previously reported VN-based supercapacitors. This work provides the possible chance for providing high operating voltage for aqueous supercapacitors, comparable even with those of batteries.