Ni2 P Interlayer and Mn Doping Synergistically Expedite the Hydrogen Evolution Reaction Kinetics of Co2 P

Interface engineering of Fe2P@CoMnP4 heterostructured nanoarrays for efficient and stable overall water splitting

Electrocatalytic water splitting to generate high-quality hydrogen is an attractive renewable energy storage technology; however, it is still far from becoming a real-world application. In this study, we developed an effective and stable nickel foam-supported Fe₂P@CoMnP₄ heterostructure electrocatalyst for overall water splitting. As expected, the as-obtained Fe₂P@CoMnP₄/NF electrocatalyst exhibits superb bifunctional catalytic activity and only requires extremely low overpotentials of 53 and 249 mV to achieve a current density of 10 mA cm^-2 for the hydrogen and oxygen evolution reactions, respectively. Moreover, a two-electrode electrolyzer assembled using Fe₂P@CoMnP₄/NF as electrodes operates at the low cell voltage of 1.54 V at 10 mA cm^-2, showing excellent long-term stability for 140 h. Theoretical calculations indicate that the surface electronic structure is effectively adjusted by the generated heterointerfaces between the Fe₂P and CoMnP₄ in a two-phase matrix, resulting in a Gibbs free energy of hydrogen adsorption close to zero and high intrinsic activity. This innovative strategy is a valuable route for producing low-cost high-performance bifunctional electrocatalysts for water splitting.

A novel bifunctional catalyst for overall water electrolysis: nano IrxMn(1-x)Oy hybrids with L12-IrMn3 phase

A nano Ir_xMn_(1-x)O_y hybrid electrode with a L1₂-IrMn₃ phase was used as a bifunctional catalyst with ultra-low iridium loading for overall water electrolysis in an acid solution for the first time. The HER activity of the Ir_xMn_(1-x)O_y hybrid electrode not only exceeded that of IrO₂, but also exceeded that of Pt/C. The OER activity of the Ir_xMn_(1-x)O_y hybrid electrode also exceeded that of IrO₂.

Janus Mo2P3 Monolayer as an Electrocatalyst for Hydrogen Evolution

The rational design of low-cost electrocatalysts with the desired performance is the core of the large-scale hydrogen production from water. Two-dimensional materials with high specific surface area and excellent electron properties are ideal candidates for electrocatalytic water splitting. Herein, we identify a hitherto unknown Mo₂P₃ monolayer with a Janus structure (i.e., out-of-plane asymmetry) through first-principle structure search calculations. Its inherent metallicity ensures good electrical conductivity. Notably, its catalytic activity is comparable to that of Pt and the density of active sites is up to 2.65 × 10¹⁵ site/cm² owing to the Mo → P charge transfer enhancing the catalytic activity of P atoms and asymmetric structure exposing more active sites to the surface. The Mo₂P₃ monolayer can spontaneously produce hydrogen through the Volmer-Heyrovsky pathway. These excellent performances can be well maintained under strain. The coexistence of covalent and ionic bonds results in Mo₂P₃ having high stability. All these excellent properties make the Mo₂P₃ monolayer a promising candidate for electrocatalytic water splitting.

Prolonged-Photoresponse-Lifetime Ni2P Nanocrystalline with Highly Exposed (001) for Efficient Photoelectrocatalytic Hydrogen Evolution

Seeking highly efficient non-preference electrocatalytic materials that serve photoelectrochemical (PEC) water splitting in acidic systems is expectant in the context of environmentally friendly production. We designed Ni₂P electrocatalysts synthesized in oil phases via the hot-bubbling method with superb stability in air and sulfuric acid solution for PEC, which were found with excellent hydrogen evolution performance. A tunable particle size and highly exposed (001) planes of Ni₂P nanocrystals were achieved. The designed catalysts achieved a notable promotion in the hydrogen evolution reaction activity compared to that of Ni₂P synthesized in the water phase. More specifically, the electrode prepared by self-assembled Ni₂P nanoparticles was found to have decent over-potential of η₁₀ = 164 mV in darkness and was further decreased to 129 mV with irradiation of visible light. The cyclic stability tests manifested brilliant durability in 0.5 M H₂SO₄. Measurement of the transient photocurrent response and PEC water splitting catalytic performance indicated that the Ni₂P had high carrier concentration upon irradiation, lower carrier recombination probability, and prolonged photo-response lifetime (3.03-3.14 s).