催化学报 ›› 2024, Vol. 66: 212-222.DOI: 10.1016/S1872-2067(24)60121-X

• 论文 • 上一篇    下一篇

具有蜂窝碳结构的杂原子掺杂NiX/Ni纳米复合催化剂高效电催化H2O2合成

刘梦然a,1, 刘灿豫a,1, 杨天芳b, 胡仕祥a, 李思韵a, 刘仕哲b, 刘洋a, 陈野a, 葛炳成a,*(), 高书燕a,b,*()   

  1. a河南师范大学材料科学与工程学院, 河南新乡 453007
    b河南师范大学化学化工学院, 河南新乡 453007
  • 收稿日期:2024-07-01 接受日期:2024-08-22 出版日期:2024-11-18 发布日期:2024-11-10
  • 通讯作者: *电子信箱: shuyangao@htu.cn (高书燕),gebingcheng@htu.edu.cn (葛炳成).
  • 作者简介:1共同第一作者.
  • 基金资助:
    国家自然科学基金(U52272293);中国博士后科学基金(2021M701116);中国博士后科学基金(2021M690930)

High-efficiency electrochemical H2O2 synthesis by heteroatom-doped NiX/Ni nanocomposites with honeycomb-like porous carbon

Mengran Liua,1, Canyu Liua,1, Tianfang Yangb, Shixiang Hua, Siyun Lia, Shizhe Liub, Yang Liua, Ye Chena, Bingcheng Gea,*(), Shuyan Gaoa,b,*()   

  1. aSchool of Materials Science and Engineering, Henan Normal University, Xinxiang 453007, Henan, China
    bSchool of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang 453007, Henan, China
  • Received:2024-07-01 Accepted:2024-08-22 Online:2024-11-18 Published:2024-11-10
  • Contact: *E-mail: shuyangao@htu.cn (S. Gao),gebingcheng@htu.edu.cn (B. Ge).
  • About author:1Contributed equally to this work.
  • Supported by:
    National Natural Science Foundation of China(U52272293);Fellowship of China Postdoctoral Science Foundation(2021M701116);Fellowship of China Postdoctoral Science Foundation(2021M690930)

摘要:

通过二电子(2e-)氧还原反应(ORR)合成过氧化氢(H2O2)是有望取代传统能源密集型蒽醌工艺的技术之一, 但是2e- ORR生成H2O2途径与4e-生成H2O途径存在竞争关系, 因此制备高选择性、高活性的催化剂是有效促进电催化ORR合成H2O2的关键. 基于密度泛函理论(DFT)得到的火山图结果表明, 在电催化2e- ORR中碳负载镍基催化剂(Ni@NC)靠近火山图顶点, 具有巨大应用潜力, 然而Ni@NC仍存在Ni位点与关键中间体*OOH吸附强度不佳的问题, 因此增强中间体*OOH的吸附强度以提高其选择性是一项挑战.

本文采用强电负性O/S原子掺杂调控催化活性中心Ni原子电子结构, 利用盐酸多巴胺聚合的碱性氛围制备富O/S掺杂的前驱体, 结合自牺牲模板铸造法通过控制煅烧温度成功合成一种NiO或者NiS掺杂的具有多孔结构蜂窝状纳米复合催化剂(NiO/Ni@NCHS或NiS6/Ni@NCHS). X射线衍射(XRD)和X射线光电子能谱(XPS)等分析测试结果明确了催化活性中心组分及局域原子配位环境对催化活性位点的影响. 与Ni配位的O/S原子可以调节Ni原子的电子结构, 从而改善Ni原子与中间体*OOH的吸附能力. 采用自牺牲模板法构造高比表面积、介孔分布的蜂窝状结构聚苯乙烯(PS)微球, 加速了活性物种在电解质中的转移, 提高了活性位点暴露程度, 改善了电催化活性. 得益于蜂窝状结构和O/S杂原子掺杂的共同作用, 在700 ºC下合成的催化剂(NiO/Ni@NCHS-700)在碱性电解液中0.1-0.6 V的电位范围内表现出89.1%的H2O2选择性, 并且H2O2产率高达1.47 mol g-1 cat h-1@0.2 V, 优于大多数先进的催化剂. 同时, NiS6/Ni@NCHS催化剂表现出91.3%的2e- ORR选择性, 1.85 mol g-1 cat h-1@0.3 V的H2O2产率等较好的电催化性能. 通过原位红外(ATR-FIIR)光谱技术和拉曼测试追踪氧还原反应过程的中间体, 结果表明, OOHad在NiO/Ni@NCHS催化剂的ORR过程中起主要作用. 密度泛函理论计算了ORR每一步所需的热力学自由能, 验证了NiO/Ni@NCHS(或NiS6/Ni@NCHS)中杂原子的掺入有效调节了Ni的强吸附特性. 同时, 金属Ni及其氧化物(或硫化物)之间的协同效应显著增强了催化活性.

综上, 本文研究了新型多组分催化剂的制备策略, 通过调控掺杂元素、孔结构和比表面积, 实现优化催化性能与反应选择性, 为高效Ni基2e- ORR电催化剂的合理设计与调控提供思路, 为推动电催化2e- ORR产H2O2技术发展提供参考.

关键词: NiX/Ni@NCHS复合催化剂, 2e-氧还原反应, 蜂窝状多孔碳, 密度泛函理论, 电催化

Abstract:

Transition metal Ni anchored in carbon material represents outstanding 2e- oxygen reduction reaction (ORR) catalytic selectivity, but enhancing the adsorption strength of intermediate *OOH to promote its selectivity remains a major challenge. Herein, the NiX/Ni@NCHS composite catalyst with heteroatom doping (O,S) is modulated by controlling partial pyrolysis strategies on honeycomb-like porous carbon to manipulate the electronic structure of the metal Ni. With the synergistic effect of honeycomb structure and O atom, NiO/Ni@NCHS-700 exhibits an exceptional H2O2 selectivity of above 89.1% across a wide potential range from 0.1 to 0.6 V in an alkaline electrolyte, and an unexpected H2O2 production rate up to 1.47 mol gcat-1 h-1@0.2 V, which outperforms most of the state-of-the-art catalyst. Meanwhile, NiS/Ni@NCHS exhibits excellent electrocatalytic performance, with 2e- ORR selectivity of 91.3%, H2O2 yield of 1.85 mol gcat-1 h-1@0.3 V. Density functional theory simulations and experiments results reveal that the heteroatom doping (O,S) method has been employed to regulate the adsorption strength of Ni atoms with *OOH, and combined with the self-sacrificing template-assisted pyrolysis approach to improve the microstructure of catalysts and optimize the active site. The heteroatom doping method in this work provides significant guidance for promoting 2e- ORR electrocatalysis to produce H2O2.

Key words: NiX/Ni@NCHS composite catalyst, 2e- oxygen reduction reaction, Honeycomb-like porous carbon, Density functional theory, Electrocatalysis