Puffing quaternary FexCoyNi1-x-yP nanoarray via kinetically controlled alkaline etching for robust overall water splitting  

碱刻蚀法构建膨化FexCoyNi1-x-yP四元阵列及其高效裂解水性能

作　　者：Haiqing Wang Xiaowei Zhang Jingang Wang Huiling Liu Shuxian Hu Weijia Zhou Hong Liu Xun Wang 王海青;张小委;王金刚;刘慧玲;胡淑贤;周伟家;刘宏;王训(Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of Shandong,Institute for Advanced Interdisciplinary Research(iAIR),University of Jinan,Jinan 250022,China;Institute for New Energy Materials and Low-Carbon Technologies,School of Materials Science and Engineering,Tianjin Key Laboratory of Advanced Functional Porous Materials,Tianjin University of Technology,Tianjin 300384,China;Department of Physics,University of Science and Technology Beijing,Beijing 100083,China;State Key Laboratory of Crystal Materials,Shandong University,Jinan 250100,China;Department of Chemistry,Tsinghua University,Beijing 100084,China)

机构地区：[1]Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of Shandong,Institute for Advanced Interdisciplinary Research(iAIR),University of Jinan,Jinan 250022,China [2]Institute for New Energy Materials and Low-Carbon Technologies,School of Materials Science and Engineering,Tianjin Key Laboratory of Advanced Functional Porous Materials,Tianjin University of Technology,Tianjin 300384,China [3]Department of Physics,University of Science and Technology Beijing,Beijing 100083,China [4]State Key Laboratory of Crystal Materials,Shandong University,Jinan 250100,China [5]Department of Chemistry,Tsinghua University,Beijing 100084,China

出　　处：《Science China Materials》2020年第6期1054-1064,共11页中国科学（材料科学（英文版）

基　　金：This work was supported by the National Key Research and Development Program of China(2017YFB0405400);Shandong Provincial Natural Science Foundation(ZR2019BB025,2018YFJH0503 and ZR2018ZC0842);the Joint Fund of the National Natural Science Foundation Committee of China Academy of Engineering Physics(U1530401).

摘　　要：Designing and constructing bifunctional electrocatalysts with high efficiency,high stability and low cost for overall water splitting to produce clean hydrogen fuel is attractive but highly challenging.Here we constructed puffed quaternary FexCoyNi1-x-yP nanoarrays as bifunctional electrodes for robust overall water splitting.The iron was used as the modulator to manipulate the electron density of NiCoP nanoarray,which could increase the positive charges of metal(Ni and Co)and P sites.The resultant electronic structure of FexCoyNi1-x-yP was supposed to balance the adsorption and desorption of H and accelerate the oxygen evolution reaction(OER)kinetics.Moreover,the morphological structure of FexCoyNi1-x-yP was modulated through the kinetically controlled alkaline etching by using the amphoteric features of initial FeCoNi hydroxide nanowires.The resultant puffed structure has rich porosity,cavity and defects,which benefit the exposure of more active sites and the transport of mass/charge.As a result,the cell integrated with the puffed quaternary FexCoyNi1-x-yP nanoarrays as both the cathode and anode only requires the overpotentials of 25 and 230 mV for hydrogen evolution reaction(HER)and OER at the current density of 10 mA cm^-2 in alkaline media and a cell voltage of 1.48 V to drive the overall water splitting.Moreover,the puffed FexCoyNi1-x-yP demonstrates remarkable durability for continuous electrolysis even at a large current density of 240 mA cm^-2.设计和构建低成本、高效、高稳定性双功能电催化剂用于全解水生产氢气燃料是非常吸引人的研究,同时也充满挑战.我们精心构建了膨化四元FexCoyNi1-x-yP纳米阵列作为双功能电催化剂用于全解水.通过引入铁元素调节磷化镍钴的电子结构,可增加磷和金属的正电荷分布,从而可实现电催化析氢过程中对氢原子吸附脱附平衡,有利于水分子的吸附和解离.在电子调控的基础上,我们采用动力学控制碱刻蚀的方法优化催化剂的形貌结构,获得了膨化纳米阵列.膨化结构具有丰富的孔结构、空腔以及晶格缺陷,有利于更多活性位点的暴露和传质.膨化FexCoyNi1-x-yP只需25和230 mV过电势即可分别实现产氢和产氧.利用膨化FexCoyNi1-x-yP作为阳极和阴极搭建的电解池只需1.48 V即可实现全解水,并在较高电流中表现出优异的稳定性.我们期望协同优化电子和形貌结构促进电催化反应过程的研究思路对廉价高效稳定双功能电催化剂的研究有所启发.

关 键 词：puffed nanoarray morphology control alkaline etching ELECTROCATALYSIS water splitting 

分 类 号：O643.36[理学—物理化学] TQ116.2[理学—化学]