Misfit-layered Bi1.85Sr2Co1.85O7.7−δ for the hydrogen evolution reaction : beyond van der Waals heterostructures

• Main Authors: Chua, Chun Kiang, Sofer, Zdeněk, Jankovský, Ondřej, Pumera, Martin
• Other Authors: School of Physical and Mathematical Sciences
• Format: Article
• Language: English
• Published: 2015
• Subjects: DRNTU::Science::Chemistry::Physical chemistry::Electrochemistry
• Online Access: https://hdl.handle.net/10356/106881; http://hdl.handle.net/10220/25178; http://dx.doi.org/10.1002/cphc.201402836
• Institution: Nanyang Technological University

Recent research on stable 2D nanomaterials has led to the discovery of new materials for energy-conversion and energy-storage applications. A class of layered heterostructures known as misfit-layered chalcogenides consists of well-defined atomic layers and has previously been applied as thermoelectric materials for use as high-temperature thermoelectric batteries. The performance of such misfit-layered chalcogenides in electrochemical applications, specifically the hydrogen evolution reaction, is currently unexplored. Herein, a misfit-layered chalcogenide consisting of CoO2 layers interleaved with an SrO–BiO–BiO–SrO rock-salt block and having the formula Bi1.85Sr2Co1.85O7.7−δ is synthesized and examined for its structural and electrochemical properties. The hydrogen-evolution performance of misfit-layered Bi1.85Sr2Co1.85O7.7−δ, which has an overpotential of 589 mV and a Tafel slope of 51 mV per decade, demonstrates the promising potential of misfit-layered chalcogenides as electrocatalysts instead of classical carbon.