Highly Stable Vertically Oriented 2H‐NbS2 Nanosheets on Carbon Nanotube Films toward Superior Electrocatalytic Activity

Abstract 2D metallic transition‐metal dichalcogenides (MTMDCs) have attracted widespread research interest in the exploration of fundamental physical issues and energy‐related fields. Although relatively high catalytic activity has been predicted theoretically in the new type MTMDCs‐based electrocatalysts, their hydrogen evolution reaction (HER) performance is severely hampered by the insufficient catalytic stability due to structural degradation during long‐time use and limited active sites in planar electrode structures. Herein, the scalable synthesis of vertically‐oriented 2H‐NbS 2 nanosheets is reported on low‐cost carbon nanotube (CNT) film substrates by a facile chemical vapor deposition route. The 3D vertically‐oriented 2H‐NbS 2 nanosheets present abundant edge active sites and strong interface coupling with CNT thus possessing exceptional mechanical stability. These features impart the 3D nanosheets catalysts with remarkably low overpotentials of ≈55 mV at 10 mA cm −2 and ultra‐high exchange current density of ≈1445 µA cm −2 , and negligible performance degradation after 200 h operation at the large current density, which are superior to those of other TMDCs‐based catalysts. This work hereby provides novel perspectives for the batch synthesis and application of 3D MTMDCs‐based electrocatalysts with greatly improved electrocatalytic performance and stability that are needed for practical applications.