Nenavathu Bhavani P, Kandula Syam, Verma Swati
Department of Applied Sciences and Humanities, Indira Gandhi Delhi Technical University for Women Delhi 110006 India
Advanced Materials Institute for BIN Convergence Technology (BK21 Plus Global Program), Department of BIN Convergence Technology, Chonbuk National University 567, Baekje-daero, Deokjin-gu Jeonju-si Jeollabuk-do 54896 Republic of Korea.
RSC Adv. 2018 May 31;8(35):19659-19667. doi: 10.1039/c8ra02237b. eCollection 2018 May 25.
Photocatalysts suffer from a lack of separation of photogenerated excitons due to the fast recombination of charge carriers, so a strong synergistic effect exhibited by photocatalysts is promising for effective photocatalysis. Herein, we have synthesized efficient visible light functionalized graphene oxide nanosheet (FGS)/ZnO nanocomposite photocatalysts a simple and economical approach with large scale production for practical applications. A series of nanocomposites (FGS/ZnO NCs) with different amounts by weight of graphene oxide (GO) have been synthesized a facile solution route followed by calcination under environmental conditions. The phase, purity and morphological studies of the synthesized FGS/ZnO NCs were carried out using powder X-ray diffraction (XRD) and transmission electron microscopy (TEM). The optical properties were studied using UV-visible diffuse reflectance spectroscopy (DRS) and photoluminescence spectroscopy (PL). XRD results confirm the formation of a pure phase of ZnO in the FGS/ZnO NCs and TEM results show strongly adhered ZnO NPs on the surface of the FGS. DRS results confirm the extension of light absorption in the visible region while PL results confirm the effective separation of charge carriers in 0.09 wt% FGS/ZnO NCs. The synthesized photocatalyst efficiently degrades carcinogenic safranin-T dye under visible light illumination which is reported for the first time using FGS/ZnO nanocomposites. Photocatalytic studies confirm the higher photocatalytic activity of 0.09 wt% FGS/ZnO NCs (about 94.5%) towards the photodegradation of safranin-T dye in aqueous solution under visible light. The improved photocatalytic activity of 0.09 wt% FGS/ZnO NCs can be ascribed to the integrative synergistic effects of the enhanced adsorption capacity of safranin-T dye, effective separation of photogenerated excitons and effective interfacial hybridization of FGS and ZnO NCs. The generation of reactive oxygen species was confirmed using terephthalic acid as a probe molecule and a scavenger test was conducted in presence of histidine.
由于光生载流子的快速复合，光催化剂存在光生激子分离不足的问题，因此光催化剂所表现出的强协同效应有望实现有效的光催化。在此，我们通过一种简单且经济的方法合成了高效的可见光功能化氧化石墨烯纳米片（FGS）/ZnO纳米复合光催化剂，该方法可大规模生产以用于实际应用。通过简便的溶液法，随后在环境条件下煅烧，合成了一系列不同重量百分比氧化石墨烯（GO）的纳米复合材料（FGS/ZnO NCs）。使用粉末X射线衍射（XRD）和透射电子显微镜（TEM）对合成的FGS/ZnO NCs进行了物相、纯度和形态学研究。使用紫外可见漫反射光谱（DRS）和光致发光光谱（PL）研究了光学性质。XRD结果证实了FGS/ZnO NCs中形成了纯相的ZnO，TEM结果表明ZnO纳米颗粒牢固地附着在FGS表面。DRS结果证实了可见光区域光吸收的扩展，而PL结果证实了0.09 wt% FGS/ZnO NCs中电荷载流子的有效分离。首次报道了使用FGS/ZnO纳米复合材料，合成的光催化剂在可见光照射下能有效降解致癌性番红T染料。光催化研究证实了0.09 wt% FGS/ZnO NCs在可见光下对水溶液中番红T染料光降解具有较高的光催化活性（约94.5%）。0.09 wt% FGS/ZnO NCs光催化活性的提高可归因于番红T染料吸附能力增强、光生激子有效分离以及FGS与ZnO NCs有效界面杂化的综合协同效应。使用对苯二甲酸作为探针分子证实了活性氧物种的产生，并在组氨酸存在下进行了清除剂测试。
