A subtle functional design of hollow CoP@MoS2 hetero-nanoframes with excellent hydrogen evolution performance.

[Display omitted] • An exquisite externally layered and internally hollow CoP@MoS 2 electrocatalyst was successfully prepared. • CoP can effectively enhance the catalytic ability of MoS 2 on hydrogen evolution reaction. • The externally layered and internally hollow nanostructure can accelerate the transfer of charge and mass. As the star material among nonprecious electrocatalysts, molybdenum disulfide (MoS 2) has received much attention. However, the catalytic inertness of the basal plane, low conductivity of its steady state (2H phase), and the agglomeration of lamellar structures have seriously hindered its catalytic performance. It is very essential to design and modulate the morphology and phase of MoS 2 to improve the above issues by synergistic regulation of electrical structure and defect engineering. Herein, MoS 2 was delicately composited on CoP nanoframe derived from a typical metal–organic frame nanostructure (ZIF-67), forming the hollow CoP@MoS 2 hetero-nanoframe. This exquisite externally layered and internally hollow CoP@MoS 2 electrocatalyst demonstrated excellent catalytic performance for the hydrogen evolution reaction, with a low overpotential of 119 mV at 10 mA cm−2, a small Tafel slope of 49 mV dec−1, a large electric double-layer capacitance of 10.28 mF cm−2, and prominent long-term stability. The remarkable catalytic performance of hollow CoP@MoS 2 hetero-nanoframe can be attributed to the unique architecture of the hetero-nanostructures, appropriate component ratios, strong interaction between CoP and MoS 2 , and large-scale defects and disorder. First-principles density-functional theory calculations can prove the above arguments adequately, the hydrogen adsorption free energy of CoP@MoS 2 is close to zero. [ABSTRACT FROM AUTHOR]