Transition metal phosphide catalysts for hydrogen oxidation reaction

Breaking Surface Atomic Monogeneity of Rh2 P Nanocatalysts by Defect-Derived Phosphorus Vacancies for Efficient Alkaline Hydrogen Oxidation

Breaking atomic monogeneity of catalyst surfaces is promising for constructing synergistic active centers to cope with complex multi-step catalytic reactions. Here, we report a defect-derived strategy for creating surface phosphorous vacancies (P-vacancies) on nanometric Rh2 P electrocatalysts toward drastically boosted electrocatalysis for alkaline hydrogen oxidation reaction (HOR). This strategy disrupts the monogeneity and atomic regularity of the thermodynamically stable P-terminated surfaces. Density functional theory calculations initially verify that the competitive adsorption behavior of Had and OHad on perfect P-terminated Rh2 P{200} facets (p-Rh2 P) can be bypassed on defective Rh2 P{200} surfaces (d-Rh2 P). The P-vacancies enable the exposure of sub-surface Rh atoms to act as exclusive H adsorption sites. Therein, the Had cooperates with the OHad on the peripheral P-sites to effectively accelerate the alkaline HOR. Defective Rh2 P nanowires (d-Rh2 P NWs) and perfect Rh2 P nanocubes (p-Rh2 P NCs) are then elaborately synthesized to experimentally represent the d-Rh2 P and p-Rh2 P catalytic surfaces. As expected, the P-vacancy-enriched d-Rh2 P NWs catalyst exhibits extremely high catalytic activity and outstanding CO tolerance for alkaline HOR electrocatalysis, attaining 5.7 and 14.3 times mass activity that of p-Rh2 P NCs and commercial Pt/C, respectively. This work sheds light on breaking the surface atomic monogeneity for the development of efficient heterogeneous catalysts.

Spontaneous Formation of >90% Optically Transmissive, Electrochemically Active CoP Films for Photoelectrochemical Hydrogen Evolution

Earth-abundant catalysts for the hydrogen-evolution reaction require increased mass loadings, relative to Pt films, to achieve comparable activity and stability in acidic electrolytes. We report herein that spontaneous nanostructuring of opaque, electrodeposited CoP films, 40-120 nm in thickness, leads to transparent electrocatalyst films that exhibit up to 90% optical transmission in the visible spectrum. The photocurrent density under simulated sunlight at a representative n⁺p-Si(100)/CoP photocathode increases by 200% after exposure to 0.50 M H₂SO₄(aq) and remains stable for 12 h of continuous operation. Atomic force microscopy and scanning electron microscopy of the film before and after exposure to 0.50 M H₂SO₄(aq) validate an optical model for transparent CoP films as probed with spectroscopic ellipsometry.

Novel synthesis of a NiMoP phosphide catalyst in a CH4-CO2 gas mixture

NiMo bimetallic phosphide was synthesized from its corresponding oxidic precursor in a 1 : 1 CH₄ : CO₂ gas mixture for the first time. The in situ synthesized NiMoP phase in the feed for CH₄-CO₂ reforming can exhibit a higher activity compared to the one prepared in H₂.

The influence of polyethylene glycol on the synthesis and activity of MoP for the hydrodechlorination of trichloroethylene

We investigated the effect of PEG on the catalytic activity of MoP for the hydrodechlorination of trichloroethylene, and found that when the average molecular mass of PEG was 8000, the MoP catalyst gave the highest activity.

Hydrogen evolution catalyzed by cobalt-promoted molybdenum phosphide nanoparticles

Co-promoted molybdenum phosphide nanoparticles have been successfully prepared and explored for the first time as a cost-effective electrocatalyst for hydrogen evolution reaction (HER).

Stability and bonding of new superalkali phosphide species

New superalkali phosphide species (F₂Li₃P, F₂Li₃P₂, and F₄Li₆P) are investigated using CBS-QB3 composite method and intriguing structural features are presented.