碘掺杂Bi4O5Br2可见光催化降解2,4-二羟基苯甲酸甲酯

2,4-二羟基苯甲酸甲酯（MDB），是对羟基苯甲酸甲酯在高级氧化过程中形成的的较稳定中间产物，具有比甲酯更强的毒性，其在环境中的存在对水资源及生态系统具有较高的潜在风险. 本文首次在可见光照射下催化降解2,4-二羟基苯甲酸甲酯，并取得了较好的进展. 与纯Bi4O5Br2相比，I-doped Bi4O5Br2催化剂表现出优异的可见光降解2,4-二羟基苯甲酸甲酯活性，其降解速率接近是纯Bi4O5Br2的5倍（0.038 min-1）. I-doped Bi4O5Br2光催化活性增强的主要原因是其更佳的光生电子空穴对的分离效率和更宽的光吸收范围. 机理研究表明，光生空穴和超氧自由基为MDB可见光催化降解过程中的主要活性氧化物种.

Photocatalytic Degradation of Methyl 2,4-Dihydroxybenzoate with I-doped Bi4O5Br2 under Visible Light #br# Irradiation

Methyl 2, 4-dihydroxybenzoate (MDB) is a relatively stable hydroxylated product of methylparaben (MeP) during advanced oxidation process (AOPs), which has more toxicity than pure MeP. And its presence in the environment will caused potential risks to ecosystems. Photocatalytic degradation of MDB was performed for the first time under visible light irradiation using I-doped Bi4O5Br2 photocatalyst. Compared with pure Bi4O5Br2, I-doped Bi4O5Br2 photocatalyst exhibited enhanced photocatalytic activity (0.038 min-1) in the degradation of MDB under visible light, showing approximately 5 times than that of pure Bi4O5Br2. The better separation efficiencies of the photogenerated electron-hole pairs and visible light absorption are considered to be the key reasons for the enhanced photocatalytic activity of I-doped Bi4O5Br2. Photogenerated holes and superoxide radicals were identified as the main reactive species by scavenger experiments.