Efficient nitrogen fixation under ambient conditions is an exigent task in both basic research and industrial applications. Recently, reduction of N2 to NH3 based on photocatalysis and/or electrocatalysis offers a possible route to the typical Haber–Bosch process. However, achieving a high yield of N2 reduction reaction (NRR) is still a challenging goal because of the limitations of efficient catalysts. Herein, we propose a photoelectrochemical NRR route based on the rational design of MoS2@TiO2 semiconductor nanojunction catalysts through a facile hydrothermal synthetic method. The developed MoS2@TiO2 photocathode attains a high NH3 yield rate (1.42 × 10–6 mol h–1 cm–2) and a superhigh faradaic efficiency (65.52%), which is the highest record to the best of our knowledge. Moreover, MoS2@TiO2 exhibits high stability over 10 consecutive reaction cycles. Therefore, this work demonstrates an effective NRR photoelectrocatalyst and results in a breakthrough in the low faradaic efficiency because of the interfacial electronic coupling and synergistic effects between the MoS2 and TiO2 components.

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Ammonia is the main precursor for the production of fertilizers, a hydrogen energy carrier and an emerging clean fuel that plays a crucial role in sustaining life on the globe.

The use of graphene‐based composite as anti‐corrosion and protective coatings for metallic materials is still a provocative topic worthy of debate. Nickel–graphene nanocomposite coatings have been successfully fabricated onto the mild steel by electrochemical co‐deposition technique. This research demonstrates the properties of nickel–graphene composite coatings influenced by different electrodeposition current densities. The effect of deposition current density on the; surface morphologies, composition, microstructures, grain sizes, mechanical, and electrochemical properties of the composite coatings are executed. The coarseness of deposited coatings increases with the increasing of deposition current density. The carbon content in the composite coatings increases first and then decreases by further increasing of current density. The improved mechanical properties and superior anti‐corrosion performance of composite coatings are obtained at the peak value of current density of 9 A dm−2. The incorporation of graphene sheets into nickel metal matrix lead to enhance the micro hardness, surface roughness, and adhesion strength of produced composite coatings. Furthermore, the presence of graphene in composite coating exhibits the reduced grain sizes and the enhanced erosion–corrosion resistance properties.

Hierarchical CoFe-LDH@g-C3N4 heterostructures have been synthesized via a facile and easily scalable in situ solvothermal method for efficient overall water splitting.

The development of durable, low-cost, and efficient photo-/electrolysis for the oxygen and hydrogen evolution reactions (OER and HER) is important to fulfill increasing energy requirements. Herein, highly efficient and active photo-/electrochemical catalysts, that is, CoMn-LDH@g-C N hybrids, have been synthesized successfully through a facile in situ co-precipitation method at room temperature. The CoMn-LDH@g-C N composite exhibits an obvious OER electrocatalytic performance with a current density of 40 mA cm at an overpotential of 350 mV for water oxidation, which is 2.5 times higher than pure CoMn-LDH nanosheets. For HER, CoMn-LDH@g-C N (η =-448 mV) requires a potential close to Pt/C (η =-416 mV) to reach a current density of 50 mA cm . Furthermore, under visible-light irradiation, the photocurrent density of the CoMn-LDH@g-C N composite is 0.227 mA cm , which is 2.1 and 3.8 time higher than pristine CoMn-LDH (0.108 mA cm ) and g-C N (0.061 mA cm ), respectively. The CoMn-LDH@g-C N composite delivers a current density of 10 mA cm at 1.56 V and 100 mA cm at 1.82 V for the overall water-splitting reaction. Therefore, this work establishes the first example of pure CoMn-LDH and CoMn-LDH@g-C N hybrids as electrochemical and photoelectrochemical water-splitting systems for both OER and HER, which may open a pathway to develop and explore other LDH and g-C N nanosheets as efficient catalysts for renewable energy applications.