物理化学学报 >> 2015, Vol. 31 >> Issue (8): 1567-1574.doi: 10.3866/PKU.WHXB201506171

催化和表面科学 上一篇    下一篇

纳米氧化锰负载钛基电催化膜制备及其苯甲醇催化氧化性能

田文杰1,2,王虹1,2,尹振1,3,*(),杨映1,2,李建新1,2,*()   

  1. 1 天津工业大学,分离膜与膜过程省部共建国家重点实验室,天津300387
    2 天津工业大学材料科学与工程学院,天津300387
    3 天津工业大学,环境与化学工程学院,天津300387
  • 收稿日期:2015-01-20 发布日期:2015-08-12
  • 通讯作者: 尹振,李建新 E-mail:yinzhen@tjpu.edu.cn;jxli@tjpu.edu.cn
  • 基金资助:
    国家自然科学基金(21206119, 21303119);长江学者和创新团队发展计划(IRT13084)

Preparation of Nano-Manganite Loaded Titanium Electocatalytic Membrane for the Catalytic Oxidation of Benzyl Alcohol

Wen-Jie. TIAN1,2,Hong. WANG1,2,Zhen. YIN1,3,*(),Ying. YANG1,2,Jian-Xin. LI1,2,*()   

  1. 1 State Key Laboratory of Separation Membranes and Membrane Processes, Tianjin Polytechnic University, Tianjin 300387, P. R. China
    2 School of Materials Science and Engineering, Tianjin Polytechnic University, Tianjin 300387, P. R. China
    3 School of Environmental and Chemical Engineering, Tianjin Polytechnic University, Tianjin 300387, P. R. China
  • Received:2015-01-20 Published:2015-08-12
  • Contact: Zhen. YIN,Jian-Xin. LI E-mail:yinzhen@tjpu.edu.cn;jxli@tjpu.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(21206119, 21303119);Changjiang Scholars and InnovativeResearch Team in University of Ministry of Education of China(IRT13084)

摘要:

利用乳液法制备出MnOx纳米颗粒,将其负载于微孔管式钛膜制得MnOx负载钛基电催化膜(MnOx/Ti).运用X射线衍射(XRD)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)、循环伏安法(CV)和计时电流法(CA)等表征方法系统考察了不同焙烧温度下MnOx晶型结构、MnOx/Ti催化膜电化学性能以及催化氧化苯甲醇的变化规律.结果表明:随着焙烧温度的升高, MnOx的晶型由初始的Birnessite-MnO2逐渐转变为K0.27MnO2,再由Mn3O4最终转变为α-MnO2.所得MnOx/Ti膜中, α-MnO2晶粒尺寸小于30 nm,结晶度较高,颗粒分布均匀.同时,由于其含有不饱和配位的锰原子和氧空位以及与基体Ti之间存在键合作用,表现出优异的电化学性能和催化性能.以450 ℃焙烧所得的α-MnO2/Ti为阳极构建电催化膜反应器催化氧化苯甲醇.在反应温度为25 ℃, 50mmol·L-1苯甲醇水溶液,电流密度为2 mA·cm-2,停留时间为15 min的条件下,膜反应器苯甲醇转化率达64%,苯甲醛选择性为79%.

关键词: 多孔钛膜, 电催化膜反应器, 锰氧化物, 苯甲醇, 催化氧化

Abstract:

MnOx nanoparticles obtained by the emulsion method were loaded on a microporous tubular titanium membrane to prepare a functional MnOx/Ti electrocatalytic membrane. The effects of calcination temperature on the crystal structure of MnOx as well as the electrochemical properties and catalytic performance to oxidize benzyl alcohol of MnOx/Ti membrane were systematically investigated by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), cyclic voltammetry (CV), chronoamperometry (CA), and other characterization methods. The results indicated that the crystal structure of MnOx was gradually transformed from Birnessite-MnO2 to K0.27MnO2, and finally to α-MnO2 from Mn3O4 with increasing calcination temperature. The α-MnO2 particles in the MnOx/Ti electrocatalytic membrane showed high crystallinity and uniform particle size (less than 30 nm). The superior electrochemical properties and catalytic performance of α-MnO2/Ti membrane obtained at a calcination temperature of 450 ℃ could be attributed to the binding effects between unsaturated coordination atoms of Mn and oxygen vacancies with the Ti substrate. The α-MnO2/Ti membrane obtained at 450 ℃ was used as the anode to assemble an electrocatalytic membrane reactor to oxidize benzyl alcohol. 64% conversion of benzyl alcohol and 79% selectivity to benzaldehyde was achieved under the operating conditions: reaction temperature 25 ℃, aqueous benzyl alcohol solution of 50 mmol·L-1, current density 2 mA·cm-2, and residence time 15 min.

Key words: Porous titanium membrane, Electrocatalytic membrane reactor, Manganite, Benzyl alcohol, Catalytic oxidation

MSC2000: 

  • O643