Das Dhananjoy, Das Mainak, Sil Sayantan, Sahu Puspendu, Ray Partha Pratim
Department of Physics, Jadavpur University, Kolkata 700032, India.
Department of Physics, University of Engineering and Management, University Area, Action Area III, B/5, Newtown, Kolkata 700160, India.
ACS Omega. 2022 Jul 23;7(30):26483-26494. doi: 10.1021/acsomega.2c02472. eCollection 2022 Aug 2.
The synthesis of solar-light-responsive zinc telluride (ZnTe) nanoparticles and their composite with reduced graphene oxide (rGO-ZnTe) via a simple hydrothermal reaction is reported. The synthesized nanostructures were comprehensively characterized by a combination of X-ray diffraction and photoelectron spectroscopy, electron microscopy, UV-vis spectroscopy, photoluminescence spectroscopy and thermogravimetric analysis. The effects of graphene oxide on the crystallinity, microstructure, photo-excitation, light absorption, surface area and thermal stability of ZnTe were studied. The current-voltage (-) characteristics for both as-synthesized ZnTe and rGO-ZnTe composite-based Schottky devices were measured to estimate the charge transport parameters such as dc conductivity, photosensitivity, carrier's mobility and lifetime. The photocatalytic performance of both the materials in the degradation of an azo dye (Rhodamine B) was subsequently investigated using simulated solar light. The rGO-ZnTe composite exhibited a higher photocatalytic activity (66%) as compared to the as-synthesized ZnTe (23%), essentially due to the synergy between rGO sheets and ZnTe nanoparticles. The role of the carrier's mobility in the transportation of photo-induced charges (electrons and holes) through the complex network of the composite materials and thus facilitating the photo-degradation process is explained. In the end, the responsible reactive species for the decomposition of Rhodamine B was also interpreted.
报道了通过简单的水热反应合成太阳光响应碲化锌（ZnTe）纳米颗粒及其与还原氧化石墨烯的复合材料（rGO-ZnTe）。通过X射线衍射和光电子能谱、电子显微镜、紫外可见光谱、光致发光光谱和热重分析相结合的方法对合成的纳米结构进行了全面表征。研究了氧化石墨烯对ZnTe的结晶度、微观结构、光激发、光吸收、表面积和热稳定性的影响。测量了合成的ZnTe和基于rGO-ZnTe复合材料的肖特基器件的电流-电压（I-V）特性，以估计电荷传输参数，如直流电导率、光敏性、载流子迁移率和寿命。随后使用模拟太阳光研究了这两种材料对偶氮染料（罗丹明B）降解的光催化性能。与合成的ZnTe（23%）相比，rGO-ZnTe复合材料表现出更高的光催化活性（66%），这主要归因于rGO片层与ZnTe纳米颗粒之间的协同作用。解释了载流子迁移率在光生电荷（电子和空穴）通过复合材料复杂网络传输从而促进光降解过程中的作用。最后，还解释了负责分解罗丹明B的活性物种。
