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In this paper, a novel Pt/CoP/C photo-electro synergistic catalyst was successfully synthesized by a hydrothermal method combined with phosphorus doping treatment. The addition of Vulcan XC-72R is in favor of effectively preventing agglomeration of active catalytic sites, resulting in more uniform and smaller Pt and CoP nanoparticles. The as-obtained Pt/CoP/C shows excellent photo-electro catalytic performance for the HER with simulated solar light irradiation. The optimal hydrogen production is 5384.18 mmol h−1 g−1, which is obviously higher than that of the commercial catalyst (20 wt% Pt/C: 4608.52 mmol h−1 g−1). The research results show that introducing cobalt phosphide into the Pt catalyst can improve the electrocatalytic activity and stability for the HER; in particular, the existence of Co3O4 in Pt/CoP/C leads to an efficient photo-electro catalysis under irradiation, which significantly improves the catalytic activity of Pt. The results above provide a novel strategy for the rational design of cost-effective Pt-based composites towards a fast HER. [ABSTRACT FROM AUTHOR]

New heteroleptic dppe appended Co(III)-dithiocarbamate (dtc) complex cations with compositions [Co(S2CNEt2)2(dppe)](PF6) (Co-Et), [Co(S2CNPri2)2(dppe)](PF6) (Co-Pr) and [Co(S2CNBun2)2(dppe)](PF6) (Co-Bu) have been synthesized and characterized by microanalysis, spectroscopic methods and crystallographic analysis. The single crystal X-ray diffraction results indicated that in all three complexes, the coordination environment around Co(III) is distorted octahedral and Co(III) is coordinated to four sulfur centers of the two dtc ligands and the two phosphorus centers of the dppe ligand. These complexes serve as precursors to yield cobalt sulfide/cobalt phosphide nano-composites dCo-Et, dCo-Pr and dCo-Bu by solvothermal decomposition of Co-Et, Co-Pr and Co-Bu, respectively. The decomposed materials have been characterized by PXRD and SEM-EDAX and explored as potential electrocatalysts for both oxygen evolution and hydrogen evolution reactions in basic and acidic media, respectively. Catalytic activity is dependent on the precursor complex and best OER and HER activities are observed for dCo-Bu with an η10 of 230 mV and a Tafel slope of 192.11 mV dec−1 for the OER and an η10 of 470 mV and a Tafel slope of 126.21 mV dec−1 for the HER. [ABSTRACT FROM AUTHOR]

The development of efficient, durable and economical catalysts based on non-precious metals for the controllable and fast hydrogen evolution from chemical hydrogen storage materials is highly desirable for the hydrogen economy. Herein, we introduce an advanced catalytic system by in situ encapsulating cobalt phosphide (CoP) nanoparticles into a quasi-metal–organic framework (quasi-Co-MOF-74) through a smart pyrolysis method. The designed synergic structure of CoP@quasi-Co-MOF-74 facilitates the efficient adsorption and activation of reactants, and achieves superior catalytic activity for the dehydrogenation of ammonia borane (AB). The extremely high hydrogen generation rate (HGR) of 9790 mL min−1 gcat−1 achieved by this catalytic system is 13.1, 4.4, and 46.5 times higher than that of quasi-Co-MOF-74, CoP, and CoP@C counterparts, respectively. Furthermore, CoP@quasi-Co-MOF-74 also delivers a high turnover frequency (TOF) of 55.9 min−1 and a low activation energy of 38.22 kJ mol−1 for the catalytic hydrolysis of AB, which compares favorably to most of the previously reported transition metal phosphide and cobalt-based catalysts. [ABSTRACT FROM AUTHOR]