Background

Most dyes have aromatic rings in their structures, which make them highly toxic for human being and aquatic life. Heterogeneous photodegradation using TiO₂ nanoparticles is one of the most applied methods used for dye removal. The wide band gap of TiO₂ nanoparticles disables its use of the visible light and thus the vast potential of sunlight. To overcome this deficiency, Ag doped TiO₂ nanoparticles were loaded on Fe-ZSM-5.

Methods

Fe-ZSM-5@TiO₂-Ag photocatalyst was synthesized through sol-gel and hydrothermal methods to remove hazardous Reactive Red 195 (RR 195) from aqueous solution.

Results

Pure phase of Fe-ZSM-5@TiO₂-Ag with specific surface area of 332 m²/g was successfully synthesized. Formation of Ti-O-Ag functional group in the photocatalyst structure confirmed the nanocomposite form of the product. SEM and TEM images portrayed the synthesized zeolite and photocatalyst NPs in a size range of ≤100 nm with homogenous distribution of Ag doped TiO₂ on Fe-ZSM-5 surface. The band-gap energy of Fe-ZSM-5@TiO₂-Ag was calculated 1.97 eV at λ = 630 nm. Photocatalytic activity of the photocatalyst under natural sunlight was investigated through photodecomposition of RR 195 in an aqueous solution. The dye photodecomposition of about 98% was achieved at photocatalyst concentration of 400 mg/L, pH of 3, and dye concentration of 50 mg/L at ambient temperature after 120 min under sunlight using 0.5 ml of TiO₂ and silver ammonium nitrate. The photocatalyst reusability was found significant after 5 frequent cycles.

Conclusion

The novel Ag-doped TiO₂-Fe-ZSM-5 nanocomposite with sunlight sensitivity can be a promising candidate to purify wastewater containing organic pollutants.

中文翻译：

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Ag 掺杂 Fe-ZSM-5@TiO2 纳米复合材料的合成、表征和光催化应用在日光照射下在水环境中降解活性红 195 (RR 195)。

背景

大多数染料的结构中都含有芳香环，这使得它们对人类和水生生物具有剧毒。_{使用 TiO 2}纳米粒子的非均相光降解是用于染料去除的最常用方法之一。_{TiO 2}纳米粒子的宽带隙使其无法利用可见光，因此无法利用太阳光的巨大潜力。为了克服这一缺陷，将Ag掺杂的TiO ₂纳米颗粒负载在Fe-ZSM-5上。

方法

采用溶胶-凝胶法和水热法合成了Fe-ZSM-5@TiO ₂ -Ag 光催化剂，用于去除水溶液中有害的活性红 195 (RR 195)。

结果

成功合成了比表面积为332 m ² /g的纯相Fe-ZSM-5@TiO _{2 -Ag。}光催化剂结构中 Ti-O-Ag 官能团的形成证实了产品的纳米复合形式。SEM 和 TEM 图像描绘了尺寸范围≤100 nm 的合成沸石和光催化剂纳米粒子，在 Fe-ZSM-5 表面上均匀分布了 Ag 掺杂的 TiO _{2 。Fe-ZSM-5@TiO 2}的带隙能量-Ag 在 λ = 630 nm 处计算为 1.97 eV。通过RR 195在水溶液中的光分解研究了该光催化剂在自然阳光下的光催化活性。在光催化剂浓度为 400 mg/L、pH 为 3 和染料浓度为 50 mg/L 的环境温度下，在阳光下使用 0.5 ml TiO ₂和硝酸铵银 120 分钟后，染料光分解率约为 98%。在 5 次频繁循环后发现光催化剂的可重复使用性显着。

结论

具有阳光敏感性的新型Ag掺杂TiO ₂ -Fe-ZSM-5纳米复合材料可以成为净化含有机污染物的废水的有希望的候选者。