School of Material Science and Engineering, Taizhou University, No. 1139, Shifu Road, Jiaojiang, 318000, China.
School of Material Science and Engineering, Central South University, No. 932, Lushan South Road, Changsha, 410083, China.
Adv Mater. 2023 Jun;35(25):e2302007. doi: 10.1002/adma.202302007. Epub 2023 Apr 29.
Nontrivial topological surface states (TSSs), which possess extraordinary carrier mobility and are protected by the bulk symmetry, have emerged as an innovative platform to search for efficient electrocatalysts toward hydrogen evolution reaction (HER). Here, a Sn-based nontrivial metal Ru Sn is prepared using electrical arc melting method. The results indicate that the (001) crystal family of Ru Sn possesses nontrivial TSSs with linear dispersion relation and large nontrivial energy window. Experimental and theoretical results demonstrate that nontrivial TSSs of Ru Sn can significantly boost charge transfer kinetics and optimize adsorption of hydrogen intermediates due to bulk symmetry-protected band structures. As expected, nontrivial Ru Sn exhibits superior HER activity to Ru, Pt/C, and trivial counterparts (e.g., Ru Sn , IrSn , and Rh Sn ) with higher ratios of noble metals. Furthermore, the wide pH-range activity of topologically nontrivial Ru Sn implies the robustness of its TSSs against pH variation during the HER. These findings provide a promising approach to the rational design of topologically nontrivial metals as highly efficient electrocatalysts.
非平凡拓扑表面态（TSS）具有非凡的载流子迁移率，并受到体对称保护，已成为寻找高效析氢反应（HER）电催化剂的创新平台。在这里，采用电弧熔炼法制备了基于锡的非平凡金属 RuSn。结果表明，RuSn 的（001）晶系具有具有线性色散关系和大非平凡能隙的非平凡 TSS。实验和理论结果表明，由于体对称保护的能带结构，RuSn 的非平凡 TSS 可以显著促进电荷转移动力学并优化氢中间体的吸附。不出所料，非平凡 RuSn 表现出优于 Ru、Pt/C 和平凡对应物（例如 RuSn、IrSn 和 RhSn）的 HER 活性，贵金属的比例更高。此外，拓扑非平凡 RuSn 在宽 pH 范围内的活性表明其 TSS 在 HER 过程中对 pH 变化具有鲁棒性。这些发现为合理设计作为高效电催化剂的拓扑非平凡金属提供了一种有前途的方法。
