Topological surface states as key catalytic elements for hydrogen-evolution reactions with the topological semimetal Cu3PdN

Topological materials, distinguished by symmetrically protected topological surface states (TSSs), have emerged as highly promising catalysts for hydrogen evolution reactions (HERs). In light of the promising potential of topological materials in catalytic processes, there is an urgent need to delve into the underlying mechanisms. In this work, our focus centers on ${\mathrm{Cu}}_{3}\mathrm{Pd}\mathrm{N}$, distinguished by its antiperovskite structure. Notably, this material exhibits a distinctive Weyl nodal chain featuring nodal loops in proximity to the Fermi level. We select ${\mathrm{Cu}}_{3}\mathrm{Pd}\mathrm{N}$ as a representative case study to explore and elucidate the intricate interplay between topological properties and catalytic performance. This work was carried out using first-principles calculations. The presence of topological nodal loops, characterized by drumhead surface states, significantly augments the surface density of states, resulting in an outstanding catalytic performance in the HER process. Remarkably, the catalytic efficiency demonstrated by this mechanism surpasses that of the benchmark catalyst $\mathrm{Pt}$. Notably, we uncover a linear correlation between the presence of TSSs and catalytic efficiency. This revelation establishes TSSs as a superior metric for characterizing the performance of topological catalysts compared to conventional descriptors such as the $d$-band center. Our study not only broadens the landscape of topological catalysis but also provides a tangible exemplar for elucidating the inherent topological mechanisms at play in these catalysts. The identification of ${\mathrm{Cu}}_{3}\mathrm{Pd}\mathrm{N}$ as a potent HER catalyst, guided by TSS properties, represents a significant advancement, offering other avenues for the design and understanding of topological materials in catalytic applications.