Efficient oxygen evolution reaction from iron-molybdenum nitride/molybdenum oxide heterostructured composites.

Integrating various active sites into a multi-component system might significantly enhance the oxygen evolution reaction (OER) performance. Herein, the as-prepared iron-molybdenum nitride/molybdenum oxide (Fe-Mo5N6/MoO3-550) composite electrocatalyst under optimum conditions demonstrates excellent electrocatalytic performance toward OER and reaches current densities of 10 and 20 mA cm-2 at overpotentials of 201 and 216 mV, respectively. The OER performance of Fe-Mo5N6/MoO3-550 exceeds that of most previously reported electrocatalytic systems. The significant improvement in the OER performance is ascribed to a combination of mechanisms. The strong electronic interactions among the Fe, Mo5N6 and MoO3 species can accelerate the OER reaction kinetics, which contributes to the OER performance. This work provides new insights into the construction of efficient electrocatalytic materials with inexpensive metals.

Synergistic catalysis of graphitic carbon nitride supported bimetallic sulfide nanostructures for efficient oxygen generation.

Herein, a series of g-C3N4 supported bimetallic sulfide nanostructures (Ni3S2/MoS2/ng-C3N4, n = 10, 20 and 30) was prepared by a hydrothermal method and subsequently a thermal annealing approach. Ni3S2/MoS2/20g-C3N4 with controlled composition exhibits efficient OER activity with a low overpotential of 183 mV at 10 mA cm-2, which outperforms the vast majority of sulfide OER electrocatalysts reported previously.

Strongly Coupled Nitrogen-Doped Mo2C@CoNi Alloy Hybrid Architecture toward Efficient Hydrogen Evolution Reaction.

Development of high-efficiency electrocatalysts for water splitting is a promising channel to produce clean hydrogen energy. Herein, we demonstrate that the combination of nitrogen-doped Mo2C and CoNi alloy to form a hybrid architecture is an effective way to produce hydrogen from electrochemical water splitting. Benefiting from a combination of mechanisms, the optimized N-Mo2C@CoNi-650 shows remarkable hydrogen evolution reaction (HER) activity with small overpotentials of 35, 123, and 220 mV to reach the current density of 10, 50, and 100 mA cm-2 in alkaline media, respectively, outperforming most previously reported HER electrocatalysts. The efficient electrocatalytic performance is ascribed to the highly exposed active sites, fast reaction kinetics, and improved charge-transfer steaming from the synergistic effect between each component. This work presents a new insight into designing and preparing highly efficient electrocatalysts toward the HER.

Synergistic optimization promoted overall water splitting of CoSe@NiSe2@MoS2 heterostructured composites.

Herein, the preparation of CoSe@NiSe2@MoS2 composites and the systematic investigation of their water splitting performance as a function of composition have been demonstrated. CoSe@NiSe2@MoS2-12 with the optimized composition exhibits a current density of 10 mA cm-2 at overpotentials of 81 and 170 mV for HER and OER in alkaline conditions, respectively. The overall water splitting device built using CoSe@NiSe2@MoS2-12 exhibited a low voltage of 1.48 V at 10 mA cm-2 due to the synergistic effects.