Coupling Interface Constructions of MoS2/Fe5Ni4S8 Heterostructures for Efficient Electrochemical Water Splitting

• Published in: Advanced materials (Weinheim) 2018-09, Vol.30 (38), p.n/a
• Main Authors: Wu, Yi, Li, Fan, Chen, Wenlong, Xiang, Qian, Ma, Yanling, Zhu, Hong, Tao, Peng, Song, Chengyi, Shang, Wen, Deng, Tao, Wu, Jianbo
• Format: Article
• Language: English
• Subjects: Chemical vapor deposition; Coupling; coupling interfaces; Density functional theory; Electrocatalysts; Heterostructures; hydrogen evolution; Hydrogen evolution reactions; Hydrogen-based energy; in situ grown molybdenum disulfide nanosheets; Materials science; Molybdenum disulfide; Organic chemistry; oxygen evolution; Oxygen evolution reactions; Performance enhancement; Platinum; Substrates; Water pollution; Water splitting
• ISSN: 0935-9648; 1521-4095
• DOI: 10.1002/adma.201803151

Water splitting is considered as a pollution‐free and efficient solution to produce hydrogen energy. Low‐cost and efficient electrocatalysts for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) are needed. Recently, chemical vapor deposition is used as an effective approach to gain high‐quality MoS2 nanosheets (NSs), which possess excellent performance for water splitting comparable to platinum. Herein, MoS2 NSs grown vertically on FeNi substrates are obtained with in situ growth of Fe5Ni4S8 (FNS) at the interface during the synthesis of MoS2. The synthesized MoS2/FNS/FeNi foam exhibits only 120 mV at 10 mA cm−2 for HER and exceptionally low overpotential of 204 mV to attain the same current density for OER. Density functional theory calculations further reveal that the constructed coupling interface between MoS2 and FNS facilitates the absorption of H atoms and OH groups, consequently enhancing the performances of HER and OER. Such impressive performances herald that the unique structure provides an approach for designing advanced electrocatalysts. Strong coupling interfaces of a vertical MoS2 array and in situ grown Fe5Ni4S8 are formed by chemical vapor deposition. The interfacial coupling of the MoS2 array on FeNi foam shows outstanding activity of both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER): 120 mV @ 10 mA cm–2 for HER and 204 mV @ 10 mA cm–2 for OER.