The crystalline‐amorphous (c‐a) interface can provide abundant accessible active sites and high intrinsic activity for hydrogen evolution reaction (HER); however, conventional methods only produce sparse c‐a interface between hetero‐phases. Here, a novel soluble dopant‐induced local self‐reconstruction strategy to yield dense c‐a nano‐interfaces is presented, as demonstrated by Mo doped‐NiP pre‐catalyst. During the cathodic polarization in alkaline electrolyte, the Mo dopant initially dissolves, generating abundant nano‐voids within the NiP nanosheets; and subsequently forms in situ ultrafine amorphous MoO3 nanoparticles, ranging from 2 to 4 nm in size, embedded in the crystalline NiP nanosheets. Compared with the conventional surface reconstruction that only generates sparse c‐a interface, the proposed “dopant‐dissolution‐redeposition”, occurred in the surface and inner local regions around dopants, can yield dense c‐a nano‐interface. Theoretical calculations reveal that the c‐a interface can efficiently modulate the electronic structure of interfacial sites and lower the HER overpotential. Benefiting from the dense c‐a nano‐interface, the amorphous/crystalline MoO3/Mo‐NiP exhibits outstanding HER performance, achieving current density of 10 mA cm−2 at ultra‐low overpotentials of 26 mV with long‐term stability in 1 M KOH. This work provides a basis for tuning the composition‐structure‐property relationships of materials from both surface and interior.

中文翻译：

---

来自碱性析氢的局部重构的致密结晶-非晶态纳米界面


结晶-非晶态 （c-a） 界面可以为析氢反应 （HER） 提供丰富的可及活性和高本征活性;然而，传统方法只能在异质相之间产生稀疏的 C-A 界面。在这里，提出了一种新的可溶性掺杂剂诱导的局部自我重建策略，以产生致密的 c-a 纳米界面，如 Mo 掺杂-NiP 预催化剂所证明的那样。在碱性电解质中的阴极极化过程中，Mo 掺杂剂最初溶解，在 NiP 纳米片内产生丰富的纳米空隙;随后在原位形成超细无定形 MoO3 纳米颗粒，尺寸从 2 到 4 nm 不等，嵌入晶体 NiP 纳米片中。与仅产生稀疏 c-a 界面的常规表面重建相比，所提出的“掺杂剂-溶解-再沉积”发生在掺杂剂周围的表面和内部局部区域，可以产生致密的 c-a 纳米界面。理论计算表明，c-a 界面可以有效地调节界面位点的电子结构并降低 HER 过电位。得益于致密的 c-a 纳米界面，非晶态/结晶 MoO3/Mo-NiP 表现出出色的 HER 性能，在 26 mV 的超低过电位下实现了 10 mA cm-2 的电流密度，并在 1 M KOH 中具有长期稳定性。这项工作为调整表面和内部材料的成分-结构-性能关系提供了基础。