物理化学学报2021，Vol.37Issue(7)：138-144,7.DOI:10.3866/PKU.WHXB202007031
胺和水插层磷酸锰仿生模拟氢键网络用于电催化水氧化
Biomimicking Hydrogen-Bonding Network by Ammoniated and Hydrated Manganese(Ⅱ)Phosphate for Electrocatalytic Water Oxidation
摘要
Abstract
Asymmetric manganese cluster,the active center of photosystem Ⅱ(PSⅡ)in nature,is hydrogen-bonded to surrounding amino acid residues and water molecules.This phenomenon is of great inspiration significance for developing and studying artificial Mn-based oxygen evolution reaction(OER)catalysts.Herein,we prepared manganese phosphate nanosheets through intercalation of ethylenediamine ions and water molecules((EDAI)(H2O)MnPi)using a simple co-precipitation method.(EDAI)(H2O)MnPi is also hydrogen-bonded to interlayer ethylenediamine ions and water molecules,forming a hydrogen-bonding network.The morphology of the(EDAI)(H2O)MnPi sample was characterized by scanning electron microscopy(SEM)and transmission electron microscopy.The thickness of(EDAI)(H2O)MnPi was characterized by atomic force microscopy.The composition and structure of(EDAI)(H2O)MnPi were characterized by X-ray diffraction(XRD)and energy dispersive X-ray spectroscopy.For control studies,manganese phosphate(EDAI)MnPi and(H2O)MnPi samples were also synthesized.The structure and morphology of(EDAI)MnPi and(H2O)MnPi samples were characterized by XRD and SEM.The difference between(EDAI)(H2O)MnPi,(EDAI)MnPi,and(H2O)MnPi were further characterized by thermal gravimetric analysis and derivative thermogravimetric analysis.Electrocatalytic properties of the(EDAI)(H2O)MnPi,(EDAI)MnPi,and(H2O)MnPi for OER were studied in 0.05 mol·L-1 pH = 7 phosphate buffered saline solution,through linear sweep voltammetry,electrochemical impedance spectroscopy,and controlled potential electrolysis(CPE)test.The electrochemical surface area(ECSA)analyses of(EDAI)(H2O)MnPi,(EDAI)MnPi,and(H2O)MnPi samples were recorded by charging currents in the non-Faradaic potential region at different scan rates.Considering the different ECSAs of different materials,the water oxidation activities of three materials were normalized by ECSA.Compared with counterparts of(EDAI)MnPi(610 mV)and(H2O)MnPi(580 mV),manganese phosphate nanosheets(EDAI)(H2O)MnPi exhibited a lower overpotential of 520 mV when driving a current density of 1 mA·cmr-2 in neutral conditions.The CPE experiment revealed that(EDAI)(H2O)MnPi remained active for at least 10 h.Manganese phosphate nanosheets containing a rich,extensive,and continuous hydrogen bond network exhibited improved OER performance in neutral conditions.The hydrogen-bonding network in manganese phosphate nanosheets has similar functions to the hydrogen-bonding network in PSⅡ,which could accelerate the transfer rate of protons and facilitate electrocatalytic water oxidation.This study may provide guidance for the design of water oxidation catalysts with rich hydrogen bond network.关键词
电催化/析氧反应/水氧化/磷酸锰/氢键Key words
Electrocatalysis/Oxygen evolution reaction/Water oxidation/Manganese phosphate/Hydrogen bond分类
化学化工引用本文复制引用
高学庆,杨树姣,张伟,曹睿..胺和水插层磷酸锰仿生模拟氢键网络用于电催化水氧化[J].物理化学学报,2021,37(7):138-144,7.基金项目
The project was supported by the Starting Research Funds of Shaanxi Normal University,and the National Natural Science Foundation of China(21773146,21872092).陕西师范大学科研启动基金和国家自然科学基金(21773146,21872092)资助项目 （21773146,21872092）
