In this work, an amorphous TiO₂ nanoparticle (8-AT) was prepared via the sol-gel route in which the pH of sol was facilely adjusted to 8 with ammonia. The characterization results of physicochemical properties revealed that as-prepared 8-AT had the particle size of 20–24 nm and specific surface area of 365.68 m²/g. The degradation of 8-AT for 20 mg·L⁻¹ tetracycline (TC) aqueous solution achieved 93.9% within 30 min dark reaction and 60 min visible light irradiation, which was 1.3 and 2.0 times higher than that of anatase TiO₂ and P25. Moreover, 8-AT can maintain a degradation capacity of 82.7% for the concentrations up to 50 mg·L⁻¹ of TC, and the degradation rate decreased slightly by 11.86% after five cycles. Based on the synergistic adsorption-photocatalytic activity of 8-AT catalyst, the possible degradation mechanism of TC was proposed. This work provided a facile method for obtaining amorphous TiO₂ through adjustment of pH and a new idea for developing efficient photodegradation catalyst.

在这项工作中，通过溶胶-凝胶途径制备了无定形 TiO _{2纳米颗粒 (8-AT)，其中溶胶的 pH 值很容易用氨水调节至 8。}理化性质表征结果表明，所制备的8-AT粒径为20-24 nm，比表面积为365.68 m 2 / ^g。8-AT对20 mg·L ^-1四环素(TC)水溶液的降解在30 min暗反应和60 min可见光照射下达到93.9%，分别是锐钛矿TiO ₂和P25的1.3和2.0倍。此外，8-AT 在浓度高达 50 mg·L ^{−1时仍可保持 82.7% 的降解能力}TC 的降解率在 5 个循环后略有下降 11.86%。基于8-AT催化剂的协同吸附-光催化活性，提出了TC的可能降解机理。该工作为通过调节pH值获得无定形TiO ₂提供了一种简便的方法，为开发高效光降解催化剂提供了新思路。