Oxidation of ammonia in dilute aqueous solutions over graphite-supported α- and β-lead dioxide electrodes (PbO2@G)

被引：81

作者：

Shih, Yu-Jen ^{[1
,3
]}

Huang, Yao-Hui ^{[1
]}

Huang, C. P. ^{[2
]}

机构：

[1] Natl Cheng Kung Univ, Dept Chem Engn, Tainan 701, Taiwan

[2] Univ Delaware, Dept Civil & Environm Engn, Newark, DE 19716 USA

[3] Natl Sun Yat Sen Univ, Inst Environm Engn, Kaohsiung 804, Taiwan

来源：

ELECTROCHIMICA ACTA | 2017年 / 257卷

关键词：

Graphite; Lead oxide; Pseudocapacitance; Ammonia oxidation; Nitrogen selectivity; Constant potential; ELECTROCHEMICAL OXIDATION; DOUBLE-LAYER; ELECTROOXIDATION; DEGRADATION; VOLTAMMETRY; BETA-PBO2; NITROGEN; WATER; ELECTROCATALYSIS; CHLORINATION;

D O I：

10.1016/j.electacta.2017.10.060

中图分类号：

O646 [电化学、电解、磁化学];

学科分类号：

081704 ;

摘要：

Graphite-supported a-and beta-PbO2 electrodes (PbO2@G) were prepared by electrochemical deposition at appropriate potentials with regard to Pb(II)/PbO2 redox couple under alkaline and acidic conditions, respectively, for studying the direct electro-oxidation of ammonia in aqueous solutions. Results of surface characterization including scanning electron microscopy (SEM), X-ray diffractometer (XRD) and X-ray photoelectron spectroscopy (XPS) indicated the presence of polymorphs of PbO2@G. Cyclic voltammetry (CV) of the electrolyte containing NH3 indicated mediation of electron transfer by PbO2. At the onset potential of ca. +1.0 to +1.45 V (vs. Hg/HgO), a pathway of NH3 oxidation to nitrogen byproducts, namely, N-2, NO2- , and NO3- was proposed. The removal efficiency and selective conversion of ammonia (0.1 M Na2SO4, pH 11, 25 degrees C) on PbO2@G was determined based on controlled potential experiments. (C) 2017 Elsevier Ltd. All rights reserved.

引用

页码：444 / 454

页数：11

共 40 条

[31]

Sogaard EG, 2014, CHEMISTRY OF ADVANCED ENVIRONMENTAL PURIFICATION PROCESSES OF WATER: FUNDAMENTALS AND APPLICATIONS, P1, DOI 10.1016/B978-0-444-53178-0.00001-8

[32] EFFECT OF TEMPERATURE ON THE FORMATION OF INDOPHENOL BLUE IN A SPECTROPHOTOMETRIC METHOD FOR THE DETERMINATION OF AMMONIA [J].