Wang Ka, Guo Weilan, Yan Shancheng, Song Haizeng, Shi Yi
School of Geography and Biological Information, Nanjing University of Posts and Telecommunications Nanjing 210023 P. R. China
National Laboratory of Solid State Microstructures, Nanjing University Nanjing 210093 P. R. China
RSC Adv. 2018 Aug 13;8(50):28684-28691. doi: 10.1039/c8ra05237a. eCollection 2018 Aug 7.
The traditional method of preparing hydrogen and oxygen as efficient clean energy sources mainly relies on the use of platinum, palladium, and other precious metals. However, the high cost and low abundance limit wide application of such metals. As such, one challenging issue is the development of low-cost and high-efficiency electrocatalysts for such purposes. In this study, we synthesized Co-FeS/CoS heterostructures a hydrothermal method for efficient hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Benefitting from their unique three-dimensional hierarchical nanostructures, Co-doped FeS, and CoS formed heterostructures on Co-FeS petals, which bestowed remarkable electrocatalytic properties upon Co-FeS/CoS nanostructures. Co-FeS/CoS effectively catalyzed the OER with an overpotential of 278 mV at a current density of 10 mA cm in 1 M KOH solution, and also is capable of driving a current density -10 mA cm at an overpotential of -103 mV in 0.5 M HSO solution. The overpotential of the OER and HER only decreased by 5 mV and 3 mV after 1000 cycles. Our Co-FeS/CoS materials may offer a promising alternative to noble metal-based electrocatalysts for water splitting.
传统的制备氢气和氧气作为高效清洁能源的方法主要依赖于使用铂、钯等贵金属。然而，高成本和低丰度限制了这些金属的广泛应用。因此，一个具有挑战性的问题是开发用于此类目的的低成本、高效率的电催化剂。在本研究中，我们采用水热法合成了Co-FeS/CoS异质结构用于高效析氢反应（HER）和析氧反应（OER）。受益于其独特的三维分级纳米结构，Co掺杂的FeS和CoS在Co-FeS花瓣上形成了异质结构，这赋予了Co-FeS/CoS纳米结构卓越的电催化性能。在1 M KOH溶液中，Co-FeS/CoS在电流密度为10 mA cm时能够以278 mV的过电位有效催化OER，并且在0.5 M H₂SO₄溶液中，在-103 mV的过电位下能够驱动-10 mA cm的电流密度。经过1000次循环后，OER和HER的过电位仅分别降低了5 mV和3 mV。我们的Co-FeS/CoS材料可能为基于贵金属的水分解电催化剂提供一种有前景的替代方案。
