Bio-reduced Ag nanoparticle decorated on ZnO for enhancement of photocatalytic reduction of hexavalent chromium and photocatalytic degradation of rhodamine B
Bio-reduced Ag nanoparticle decorated on ZnO for enhancement of photocatalytic reduction of hexavalent chromium and photocatalytic degradation of rhodamine B
复制标题
ZnO上修饰的生物还原银纳米粒子增强六价铬的光催化还原和罗丹明B的光催化降解
DOI：
10.1016/j.jallcom.2023.168797
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发表时间：
2023
影响因子：
6.2
通讯作者：
Sasaki Keiko
中科院分区：
文献类型：
--
作者：
Chuaicham Chitiphon;Rizki Intan Nurul;Sekar Karthikeyan;Shenoy Sulakshana;Srikhaow Assadawoot;Trakulmututa Jirawat;Sasaki Keiko
采用水热法将茉莉花茶叶中有机物还原后的Ag纳米粒子修饰在ZnO上，制备了AgNPs@ZnO复合材料，并将其应用于光催化降解罗丹明B（Rh B）和还原六价铬（Cr（VI））的反应中。所产生的复合材料（AgNPs@ZnO）的光学和物理化学特征，以更好地理解的AgNPs-ZnO异质结的发展相比，纯ZnO的影响。优化后的AgNPs@ZnO在60 min内对10 mg/L Cr（VI）的降解率超过95%，在180 min内对10 mg/L RhB的降解率超过95%，其中Cr的降解速率常数约为纯ZnO的5倍，RhB的降解速率常数约为纯ZnO的3倍，这是由于其上级的分离和传输光生电子-空穴对的能力，如光致发光强度的下降所证明的。此外，当AgNPs被放置在ZnO的表面上的复合材料中，表面缺陷产生的ZnO上，证实了由能量分辨分布的电子陷阱（ERDT）图案AgNPs@ZnO，表明形成新的电子陷阱水平。这可能导致能带隙的减小，从而导致光吸收的增强和电荷复合的减少。因此，AgNPs@ZnO的生物诱导复合材料为水环境光化学净化技术开辟了新的可能性。
Ag nanoparticles reduced by organic components extracted from Jasmine tea leaves were decorated by a hydrothermal reaction on ZnO to fabricate AgNPs@ZnO composite, and then the composite was applied for photocatalytic reactions to degrade rhodamine B (RhB) and reduce hexavalent chromium (Cr(VI)). The produced composite (AgNPs@ZnO) was optically and physicochemically characterized to better understand the impact of the development of the AgNPs-ZnO heterojunction when compared to that of pure ZnO. The optimized AgNPs@ZnO reduced more than 95% of 10 mg/L Cr(VI) in 60 min and degraded more than 95% of 10 mg/L RhB in 180 min, with a rate constant around five times for Cr reduction and three times for RhB degradation faster than that of pure ZnO, due to its superior capacity to separate and transport photogenerated electron-hole pairs, as evidenced by a drop in photoluminescence intensity. Furthermore, when AgNPs were placed on the surface of ZnO in the composites, surface defects were generated on ZnO, as confirmed by the energy-resolved distribution of electron trap (ERDT) pattern for AgNPs@ZnO, indicating the formation of new electron trapping levels. This might cause a reduction of the energy band gap, resulting in the enhancement of light adsorption and reduction of charge recombination. Therefore, the present bio-induced composite of AgNPs@ZnO opens up new possibilities for photochemical purification technology in aquatic environments.