Rational design and controllable synthesis of efficient and robust electrocatalysts for hydrogen evolution reaction (HER) remain a critical challenge for the renewable energy economy. Herein, heterostructured Nb4N5-xOx-MoS2 (0 < x < 1) anchored on N-doped graphene (defined as Nb4N5-xOx-MoS2/NG) is synthesized by hydrothermal and chemical vapor deposition (CVD) approaches. During the CVD process, MoS2 nanosheets are etched into small pieces and covalently interconnected with Nb4N5-xOx to form fine Nb4N5-xOx-MoS2 heterostructures, which possess abundant interfaces and fully exposed edge active sites. The as-prepared Nb4N5-xOx-MoS2 heterostructures with Nb-(N,S)-Mo bridges provide desired electron density, which exhibit excellent chemisorption ability for both H and water, significantly improving the intrinsic HER activity. Meanwhile, the covalently connected Nb4N5-xOx-MoS2 heterostructures together with chemical coupling of Nb4N5-xOx-MoS2 and N-doped graphene improve the structural stability and ensure fast electron transfer in the Nb4N5-xOx-MoS2/NG nanocomposite, further supporting the H2 generation and stability.

中文翻译：

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具有所需电子密度的共价连接的Nb4N5-xOx-MoS2杂催化剂可促进氢的释放。

合理设计和可控合成高效，稳健的氢析出电（HER）电催化剂仍然是可再生能源经济的关键挑战。在此，通过水热和化学气相沉积（CVD）方法合成锚固在掺杂N的石墨烯（定义为Nb4N5-xOx-MoS2 / NG）上的异质结构Nb4N5-xOx-MoS2（0 <x <1）。在CVD过程中，将MoS2纳米片蚀刻成小片，并与Nb4N5-xOx共价互连，以形成精细的Nb4N5-xOx-MoS2异质结构，该结构具有丰富的界面和完全暴露的边缘活性位。带有Nb-（N，S）-Mo桥的Nb4N5-xOx-MoS2异质结构可提供所需的电子密度，对H和水均具有出色的化学吸附能力，从而显着提高了固有的HER活性。与此同时，