Engineering of sugarcane bagasse based porous carbon nanofiber-supported the CoP/Co2P heterostructure for efficient overall water splitting

Pt-Doped Biomass Carbon Decorated with MoS2 Nanosheets as an Electrocatalyst for Hydrogen Evolution

It is necessary to develop an efficient hydrogen evolution catalyst to improve the efficiency of the hydrogen evolution reaction (HER). Herein, a MoS₂ nanosheet is decorated on the Pt-doping biomass yeast cells (MoS₂@Pt/YC) via a simple hydrothermal process. Reducing the noble metal loading without compromising its performance is a challenging task. The smooth surface of YCs is conducive to the growth of MoS₂ nanosheets, and its functional groups provide attachment sites for metal Pt. The Pt/YC is covered with MoS₂ nanosheets, thus improving the exposed active sites for HER. The obtained MoS₂@Pt/YC delivers a competitive overpotential of 118 mV at the benchmark current density of 10 mA cm^-2 and achieves a small Tafel slope of 74 mV dec^-1, indicating the great HER performance of MoS₂@Pt/YC. Moreover, MoS₂@Pt/YC shows robust stability after 24 h of continuous operation toward HER in acidic solution. By introducing transition metal sulfides with high specific surface area, the loading of precious metals can be reduced without compromising properties. This work provides a method to design Pt-doping HER electrocatalysts through a simple method. The facile preparation process for MoS₂@Pt/YC and its outstanding performance allow it to be a promising electrocatalyst for practical HER application.

Synergistically Coupling of Manganese-Doped CoP Nanowires Arrays with Highly Dispersed Ni(PO3)2 Nanoclusters toward Efficient Overall Water Splitting

Co-based phosphides are considered to be highly promising electrocatalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). However, their electrocatalytic efficiencies are greatly limited by the weak water dissociation process and unsatisfactory adsorption ability toward reaction intermediates. Herein, novel Mn-doped CoP/Ni(PO₃)₂ heterostructure array electrocatalysts which are composed of highly dispersed Ni(PO₃)₂ nanoclusters that are tightly wrapped on Mn-doped CoP nanowire arrays are designed. An electrocatalytic performance test suggested that the heterostructure arrays exhibited competitive electrocatalytic performance toward both HER and OER, which needed overpotentials of 116 and 245 mV to drive a current of 10 mA/cm², respectively. Encouragingly, a symmetric two electrode water splitting system constructed by the heterostructure arrays required an ultralow cell voltage, suggesting the potential in overall water splitting. First-principles calculations combined with experimental characterization were further performed to clarify the electrocatalytic mechanism. On the one hand, effective doping of Mn atoms could optimize the surface electronic structure of CoP and promote the intrinsic activity. On the other hand, the compact and abundant heterogeneous interface between Ni(PO₃)₂ and CoP not only made more active sites exposed but also promoted the effective adsorption of intermediate reaction species on the catalyst surface. This work provides a new strategy to improve electrocatalytic performance of Co-based phosphides through the synergistic coupling of metal-doping and phosphate surface decoration, which will greatly promote the development of highly efficient electrocatalysts for overall water splitting.