High Catalytic Performance of Topological Material NbSi _x Te ₂ (x = 0.33, 0.40, 0.43) Bulk Crystals in Hydrogen Evolution Reaction

ABSTRACT Topological quantum materials have recently emerged to explore high‐performance and economical hydrogen evolution reaction (HER) catalysts. As a novel kind of topological material, NbSi x Te 2 (x = 0.33, 0.40, 0.43), formed by inserting a metallic NbTe 2 chain into the semiconductor Nb 2 SiTe 4 chain, exhibits rich structural features and topological electronic states, which are advantageous for being an ideal HER catalyst in principle. In this work, we synthesized NbSi x Te 2 crystals and evaluated their electrocatalytic HER performance in experiments. The NbSi 0.43 Te 2 bulk crystal catalyst shows a series of remarkable HER properties, such as a low overpotential of 67.38 mV at 10 mA cm −2 , a Tafel slope as low as 28.68 mV dec −1 and a long‐term stability for 50 h at a high potential of −360 mV. As theoretical analyses suggest, excellent HER performance of NbSi 0.43 Te 2 bulk crystals comes from the high density of active sites, near‐zero free energy, as well as high electron mobility along NbTe 2 chains due to its nontrivial topological states. This work provides a novel and effective exploration pathway for utilizing quantum topological materials as high‐performance HER electrocatalysts.