Cobalt Phosphide Cocatalysts Coated with Porous N‐doped Carbon Layers for Photocatalytic CO₂ Reduction

Abstract

Cobalt phosphide (CoP) has been demonstrated as a cocatalyst for visible‐light‐sensitized CO2 reduction, but just with moderate selectivity, due to the competitive H2 generation reaction. Herein, the porous N‐doped carbon (NC) layer is in situ coated on the surface of CoP nanoparticles to fabricate the core‐shell CoP@NC composite cocatalyst. Benefiting from the outstanding electric conductivity and high surface area of the NC shell, the CoP@NC hybrid attains strengthened capabilities for charge separation/transfer and CO2 capture/activation. Besides, the direct contact of CoP with H2O is prevented by the porous NC shell with high hydrophobicity. Consequently, the photosensitized CO2‐to‐CO conversion efficiency and selectivity of CoP@NC hybrid are enhanced by 2.7 and 2.4 times, respectively, compared to bare CoP.

Nickel phosphonate-derived Ni2P@N-doped carbon co-catalyst with built-in electron-bridge for boosting photocatalytic hydrogen evolution

“…11 However, it should be noted that pure TMPs as co-catalysts have limitations in terms of speeding up the surface reaction of H + to H 2 due to the lack of enough active sites. 12,13 In addition, the coupling methods of TMPs with host photocatalysts are closely related to the activities of the TMP-based photocatalyst system as well. Thus, it is still necessary to further optimize TMPs to enhance photocatalytic H 2 production.…”

MOF-Derived Non-Noble Metal CoP Nanoparticle Modified TiO2 for Enhanced Photocatalytic Hydrogen Production

“…However, the decrease of the Co characteristic peak in the CoP/TiO 2 compound may be caused by the low content of CoP . P 2p has two peaks at 129.8 and 134.0 eV representing P in CoP and the oxidized P–O bond on the surface of CoP, respectively (Figure d) . The negative shift of the Co 2p and P 2p peaks was observed in the CoP/TiO 2 compound, indicating that electrons were transferred from TiO 2 to CoP …”

“…The precious metal Pt can be used as a reducing active site for photocatalytic reactions, while CoP exhibits excellent synergistic catalytic capabilities similar to that of the zerovalent metal Pt. At the same time, CoP, as a typical TMP, has a rich composition of earth elements, with the advantages of low price, high stability, and good electrical conductivity, thus attracting extensive attention in terms of non-noble cocatalyst development. ,, …”

“…Notably, CoP, composed of earth-abundant elements and as a typical TMP, displays excellent cocatalytic capacity similar to the zerovalent metal Pt, but it is cheap, highly stable, and conductive, thus attracting extensive attention in terms of non-noble cocatalyst development. , It was used to construct two-dimensional (2D)/2D heterostructure composites, in which the Schottky junction effect was amplified by the formation of a larger 2D interface area between 2D CoP and 2D g-C 3 N 4 . Therefore, the 2% CoP/CN at the optimal mass loading displayed a higher hydrogen production activity than 2% Pt/CN .…”

“…Non-noble metals, metal oxides, ,, metal carbides, metal sulfides, and metal phosphides − are potential candidates favorable for acting as cocatalysts. Therein, transition metal phosphides (TMPs) such as CoP, − Ni 2 P, Cu 3 P, MoP, and FeP are superior cocatalysts because of their low cost, excellent reactivities, and chemical stabilities.…”