MoP/Co₂P Hybrid Nanostructure Anchored on Carbon Fiber Paper as an Effective Electrocatalyst for Hydrogen Evolution

Abstract

Developing low-cost and effective electrocatalysts for the hydrogen evolution reaction (HER) to replace Pt-group metals is a continuous challenge. Recently, transition metal phosphides have received increasing attention owing to their high intrinsic activity in catalyzing HER in acidic media. Herein, we reported a novel hybrid nanostructure MoP/Co 2 P anchored on carbon fiber paper (CFP) (MoP/Co 2 P/CFP) which was achieved by a facile hydrothermal approach to obtain Co(CO 3 ) 0.35 Cl 0.20 (OH) 1.10 nanowires array (NA)/CFP, followed by deposition of MoO 2 nano-particles via chemical vapor deposition (CVD) in the presence of MoO 3 and a subsequent in situ phosphorization process. It was worth noting that the catalyst exhibited higher catalytic activity for HER in 0.5 M H 2 SO 4 solution, which afforded an overpotential of 140 mV at a current density of 10 mA cm À 2 , a Tafel slope of 80 mV dec À 1 , an exchange current density of 0.153 mA cm À 2 and a high electrochemical double-layer capacitance (C dl ) of 48.2 mF cm À 2 . Moreover, it also exhibited superior stability and durability in long-term durability test.[a] Prof. for 2 h under 10 % H 2 atmosphere with a temperature ramping rate of 5°C min À 1 . After cooling down to ambient temperature, the sample was washed with deionized water and ethanol for several times and dried naturally.

Phosphorus‐Based Electrocatalysts: Black Phosphorus, Metal Phosphides, and Phosphates

“…Second, a heterointerface can significantly increase the active sites. [ 161,162 ] The strong electronic interactions between NiFeP and NiFe‐OH generated a higher number of active sites, thus improving the electrocatalytic activity, as has confirmed by the ECSA analysis. [ 100 ] The hybrid‐type structure consisting of CuP x nanodots decorated on CoP 3 nanowires demonstrated excellent electrocatalytic activity, where there was an increase in the active sites together with morphology control by the presence of Cu.…”

“…There are several general synthesis processes for phosphides, including i) vapor–solid phosphorization reaction, where the phosphorization is carried out in a ceramic boat loaded with metal‐based precursors and P source separately in a tube furnace at high temperature filled with protective gas. The P‐source includes red phosphorus, [ 99,164,197 ] NaH 2 PO 2 , [ 92,198 ] and (NH 4 ) 2 HPO 4, [ 162 ] while the metal‐based precursors are usually the corresponding metal, metal oxides, metal hydroxides; ii) solution‐phase phosphorization reaction, where to synthesize phosphides, one can use organophosphorus as the P source, examples of which are phytic acid, [ 199,200 ] trioctylphosphine (TOP) and their analogues in organic solvents. [ 135 ] Besides, phosphide (RuP x ) can be synthesized through reducing metal salt (e.g., RuCl 3 ) and NaH 2 PO 2 as well, by adding reductant such as NaBH 4 [ 102,201 ] ; iii) solid‐state reduction, where during the phosphorization process, the P source (such as NH 4 H 2 PO 4 [ 124 ] and phosphorous acid (H 3 O 4 P) [ 179 ] ) and metal precursors were mixed, followed by high temperature reduction; and iv) phosphides from phosphate and phosphonate by calcination.…”

Construction of Ni–Mo–P heterostructures with efficient hydrogen evolution performance under acidic condition

“…The equivalent circuit diagram embedded in Fig. 6d, where R s , CPE, R ct stands for the solution resistance, constant-phase element, and charge-transfer resistance, respectively [45][46]. The semicircle diameter represents the charge transfer resistances (R ct ), which can evaluate the charge transfer capability.…”

Superaerophobic/superhydrophilic surfaces as advanced electrocatalysts for the hydrogen evolution reaction: a comprehensive review

“…The electronic structure of the catalyst and its active sites are manipulated to produce an electrocatalyst with higher intrinsic activity . [29][30][31][32] In addition, to accelerate the ratedetermining stage and improve the activity, the Gibbs free energy of adsorption for the reactants must be optimized. [33][34][35][36] Intrinsic electrocatalytic properties can be improved by selecting inherently active compounds, doping, or alloying with active elements, which tunes the electronic conguration.…”