Spatial Compartmentalization of Cobalt Phosphide in P-Doped Dual Carbon Shells for Efficient Alkaline Overall Water Splitting

Abstract

Highly durable and earth-abundant bifunctional catalysts with low cell voltage are desirable for alkaline overall water splitting in the industrial fields. Herein, a novel carbon-based CoP hybrid with spatial compartmentalization of CoP nanoparticles (NPs) in P-doped dual carbon shells is achieved via a cheap Co−glycerate-template strategy. Benefitted from the uniform atomic blending of Co 2+ ions in the Co−glycerate precursors, CoP NPs in situ formed in the confined space with NaH 2 PO 2 as phosphorus source during the annealing process; meanwhile, glycerate suffered carbonization and transformed into P-doped dual carbon shells during the annealing process, including interior thin carbon coating, closely encircled CoP NP, and peripheral hollow carbon sphere loading a lot of CoP NPs. Not only does spatial compartmentalization of CoP NPs avoid the aggregation and expose more active sites but also P-doped dual carbon shells improve the conductivity and durability of the catalyst. As expected, the optimized hybrid exhibits outstanding electrocatalytic activities in alkaline media, such as hydrogen evolution reaction (HER) overpotential of 101 mV, oxygen evolution reaction (OER) overpotential of 280 mV, and a low cell voltage of 1.66 V to deliver a current density of 10 mA cm −2 . Moreover, durability and stability are greatly improved under harsh electrochemical conditions. The current strategy shades new insight into the development of carbon-based transition metal phosphides (TMP) catalysts for electrocatalysis applications.

Co/Zn‐based bimetallic MOF ‐derived hierarchical porous Co/C composite as cathode material for high‐performance lithium‐air batteries

“…The thin carbon shell of cobalt nanoparticle can promote the diffusion/transfer of ions and electrons and enable the complete utilization of the active materials. 38 Additionally, the cobalt nanoparticles are protected by a layer of carbon that prevents corrosion, oxidation, and agglomeration.…”

Phosphorus‐Doped CuCo2O4 Oxide with Partial Amorphous Phase as a Robust Electrocatalyst for the Oxygen Evolution Reaction

“…In particular, P 2 s and 2p electrons are detected confirming the successful doping of P into the spinel CCO. [41] The high-resolution XPS spectrum of Cu 2p electrons (Figure 3a) shows that the two main peaks at the binding energies of 934.6 eV and 954.4 eV can be classified to Cu 2p 3/2 and 2p 1/2 electrons of Cu 2 + , [42] and two satellite (named as "Sat.") peaks at 962.2 eV and 942.2 eV are also detected, respectively.…”

Recent Progresses in Engineering of Ni and Co based Phosphides for Effective Electrocatalytic Water Splitting

“…[82,83][86] The study by Mohite et al . shows the CoP nanoparticles in P‐doped dual carbon shells as superior catalyst effective water splitting [85] . Another interesting work by Li group developed nanocomposites via architectural and electronic engineering of rGO/CoFe−P for producing highly active surface area for OER in alkaline medium [86] …”