Synergistic effect of Co and Fe bimetallic oxides/hydroxides composite structure as a bifunctional electrocatalyst for enhancing overall water splitting performance

Ru/NC heterointerfaces boost energy-efficient production of green H2 over a wide pH range

Overall urea electrolysis has favorable thermodynamic properties and can complement traditional water splitting by simultaneously purifying urea-rich waste streams. However, the kinetics of the reaction is slow and more efficient catalysts are required. In this work, we describe a facile way to fabricate amorphous nickel phosphides on graphene nanosheets (a-Ni2P/G), which shows high efficient performance for overall urea electrolysis. The a-Ni2P/G catalyst has abundant surface area for abundant catalytic active sites and high proportion of Ni3+ active sites, realizing a superior intrinsic activity for both hydrogen evolution reaction (HER) and urea oxidation reaction (UOR). Impressively, the a-Ni2P/G catalyst requires only much lower potentials of 1.28 V and − 0.1 V for UOR and HER at 10 mA cm−2. The assembled a-Ni2P/G║a-Ni2P/G electrolyzer needs a small cell voltage of 1.39 V to deliver the current density of 10 mA cm−2. This work highlights a promising pathway to develop a cost-efficient catalyst for energy-saving H2 generation combined with waste water purification. A highly efficient amorphous catalyst of a-Ni2P/G with high surface area and abundant exposed catalytic sites is reported. The assembled a-Ni2P/G║a-Ni2P/G system shows a quite small cell voltage of 1.39 V to deliver 10 mA cm−2, which is better than most of bifunctional catalysts.

Boosting hydrogen production via urea electrolysis on an amorphous nickel phosphide/graphene hybrid structure

Hierarchically nanostructured Ni2Fe2N as an efficient electrocatalyst for hydrazine oxidation reaction

Ni modified Co2VO4 heterojunction with poor/rich-electron structure for overall urea-rich wastewater oxidation

Nitrogen-doped-carbon coated FeCo modified CoFe2O4 nanoflowers heterostructure with robust stability for oxygen evolution and urea oxidation

Developing high performance anode catalysts for oxygen evolution reaction (OER) and hydrazine oxidation reaction (HzOR) at large current density is an efficient pathway to produce hydrogen. Herein, we synthesize a FeWO4-WO3 heterostructure catalyst growing on nickel foam (FeWO4-WO3/NF) by a combination of hydrothermal and calcination method. It shows good catalytic activity with ultralow potentials for OER (ζ10 = 1.43 V, ζ1.000 = 1.56 V) and HzOR (ζ10 = −0.034 V, ζ1.000 = 0.164 V). Moreover, there is little performance degradation after being tested for 100 h at 1,000 (OER) and 100 (HzOR) mA·cm−2, indicating good stability. The superior performance could be attributed to the wolframite structure and heterostructure: The former provides a high electrical conductivity to ensure the electronic transfer capability, and the later induces interfacial electron redistribution to enhance the intrinsic activity and stability. The work offers a brand-new way to prepare good performance catalysts for OER and HzOR, especially at large current density.

Miaojing Pan

Papers

Ni modified Co2VO4 heterojunction with poor/rich-electron structure for overall urea-rich wastewater oxidation

Nitrogen-doped-carbon coated FeCo modified CoFe2O4 nanoflowers heterostructure with robust stability for oxygen evolution and urea oxidation

Highly active bifunctional catalyst: Constructing FeWO4-WO3 heterostructure for water and hydrazine oxidation at large current density

Pyridinic-N doping carbon layers coupled with tensile strain of FeNi alloy for activating water and urea oxidation

Tensile Strain of Feni Alloy Coupled with Pyridinic-N Doping Carbon Layers for Activating Water and Urea Oxidation