Interdisciplinary Graduate School, Nanyang Technological University, 637141 Singapore, Singapore; Nanyang Environment and Water Research Institute, Nanyang Technological University, 637141 Singapore, Singapore.
Nanyang Environment and Water Research Institute, Nanyang Technological University, 637141 Singapore, Singapore; School of Civil and Environmental and Engineering, Nanyang Technological University, 639798 Singapore, Singapore.
J Colloid Interface Sci. 2017 Nov 1;505:489-499. doi: 10.1016/j.jcis.2017.05.070. Epub 2017 May 23.
With the assistance of acetic acid (CHCOOH), a novel 3D flower-like BiO was synthesized via hydrothermal process followed by calcination. For the first time, the role of CHCOOH as a capping agent in the formation of flower-like structure was investigated. The as-prepared flower-like BiO had a high activity on the degradation of sulfamethoxazole (SMX) under simulated solar light irradiation due to the narrow band gap of 2.69eV, high percentage of β-BiO as well as high intensity of polar facets (120) and (200). Meanwhile, the photocatalytic degradation followed apparent pseudo-first-order kinetics. The rate constant (k) increased from 0.7×10 to 3.0×10min with the catalyst loading varying from 0.5 to 2.0gL. Increasing pH values from 3 to 11 led to the decrease of k from 2.2×10 to 0.2×10min, which could be attributed to the electrostatic adsorption between SMX molecules and BiO. The radical quenching experiments showed both direct (h) and indirect oxidation (OH and O) happened in this process.
在醋酸（CHCOOH）的协助下，通过水热法和煅烧合成了一种新颖的 3D 花状 BiO。首次研究了 CHCOOH 在花状结构形成中作为封端剂的作用。由于 2.69eV 的窄带隙、高比例的β-BiO 以及高极性面（120）和（200）的强度，所制备的花状 BiO 在模拟太阳光照射下对磺胺甲恶唑（SMX）的降解具有很高的活性。同时，光催化降解遵循明显的拟一级动力学。随着催化剂负载量从 0.5 到 2.0gL 的变化，速率常数（k）从 0.7×10 增加到 3.0×10min。将 pH 值从 3 增加到 11 导致 k 从 2.2×10 减少到 0.2×10min，这可归因于 SMX 分子和 BiO 之间的静电吸附。自由基猝灭实验表明，该过程中同时发生直接（h）和间接氧化（OH 和 O）。
