Saraf Rohit, Shivakumara C, Behera Sukanti, Nagabhushana H, Dhananjaya N
Centre for Converging Technologies, University of Rajasthan, Jaipur 302 005, India.
Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560 012, India.
Spectrochim Acta A Mol Biomol Spectrosc. 2015 Feb 5;136 Pt B:348-55. doi: 10.1016/j.saa.2014.09.038. Epub 2014 Oct 6.
Stolzite polymorph of PbWO4 catalyst was prepared by the facile room temperature precipitation method. Structural parameters were refined by the Rietveld analysis using powder X-ray data. PbWO4 was crystallized in the scheelite-type tetragonal structure with space group I41/a (No. 88). Field emission scanning electron microscopy revealed leaf like morphology. Photoluminescence spectra exhibit broad blue emission (425 nm) under the excitation of 356 nm. The photocatalytic degradation of Methylene blue, Rhodamine B and Methyl orange dyes were measured under visible illumination. The 100% dye degradation was observed for MB and RhB dyes within 60 and 105 min. The rate constant was found to be in the decreasing order of MB>RhB>MO which followed the 1st order kinetic mechanism. Therefore, PbWO4 can be a potential candidate for blue component in white LEDs and also acts as a catalyst for the treatment of toxic and non-biodegradable organic pollutants in water.
采用简便的室温沉淀法制备了PbWO₄催化剂的钨铅矿多晶型物。利用粉末X射线数据通过Rietveld分析对结构参数进行了精修。PbWO₄以白钨矿型四方结构结晶，空间群为I41/a（编号88）。场发射扫描电子显微镜显示出叶片状形态。光致发光光谱在356 nm激发下呈现出宽的蓝色发射（425 nm）。在可见光照射下测量了亚甲基蓝、罗丹明B和甲基橙染料的光催化降解。在60和105分钟内观察到MB和RhB染料的染料降解率为100%。发现速率常数按MB>RhB>MO的顺序递减，遵循一级动力学机制。因此，PbWO₄可以成为白光发光二极管中蓝色成分的潜在候选物，并且还可作为处理水中有毒和不可生物降解有机污染物的催化剂。
