Kumar Avvaru Praveen, Bilehal Dinesh, Tadesse Aschalew, Kumar Deepak
Department of Applied Chemistry, School of Applied Natural Science, Adama Science and Technology University PO Box 1888 Adama Ethiopia
Department of Chemistry, Karnatak University Dharwad-560008 Karnataka India.
RSC Adv. 2021 Feb 4;11(11):6396-6406. doi: 10.1039/d0ra10290c. eCollection 2021 Feb 2.
This work describes photocatalytic application of γ-alumina (γ-AlO) surface-anchored palladium and palladium oxide nanoparticles (Pd-γ-AlO and PdO-γ-AlO NPs) synthesized by a novel co-precipitation technique. The palladium(0) NPs (Pd-γ-AlO) were formed by calcination of the sample in inert medium, whereas PdO NPs (PdO-γ-AlO) were obtained by calcination of the sample in atmospheric oxygen. As-synthesized Pd-γ-AlO and PdO-γ-AlO NPs are characterized by X-ray diffraction, Fourier transform-infrared spectroscopy, field emission scanning electron microscopy and photoluminescence (PL) spectra. The PL spectra of Pd-γ-AlO and PdO-γ-AlO NPs display visible-light emissions from 450 to 500 nm at room temperature. This work aims to study the photocatalytic degradation of organic dye pollutants, including bromocresol green (BCG), bromothymol blue, methylene blue and methyl orange using Pd-γ-AlO and PdO-γ-AlO NPs as potential photocatalysts. Experimental parameters, including the admitting concentration of the organic dye solution, Pd-γ-AlO and PdO-γ-AlO photocatalyst dosage, and pH, were varied to ascertain favorable conditions for photocatalytic degradation. The results indicate that the organic dye BCG is completely (100%) degraded in aqueous solution under ultraviolet light, compared with the other organic dyes. Furthermore, Pd-γ-AlO NPs showed better photocatalytic performance than PdO-γ-AlO NPs. The possible photocatalytic degradation mechanism of the organic dyes by Pd-γ-AlO and PdO-γ-AlO photocatalysts is proposed. The studies reveal that Pd and PdO NPs anchored on the γ-AlO surface are promising and effective catalysts for photocatalytic degradation of organic dyes.
本工作描述了通过一种新型共沉淀技术合成的γ-氧化铝（γ-AlO）表面锚定钯和氧化钯纳米颗粒（Pd-γ-AlO和PdO-γ-AlO NPs）的光催化应用。钯（0）纳米颗粒（Pd-γ-AlO）通过在惰性介质中煅烧样品形成，而PdO纳米颗粒（PdO-γ-AlO）通过在大气氧气中煅烧样品获得。合成的Pd-γ-AlO和PdO-γ-AlO NPs通过X射线衍射、傅里叶变换红外光谱、场发射扫描电子显微镜和光致发光（PL）光谱进行表征。Pd-γ-AlO和PdO-γ-AlO NPs的PL光谱在室温下显示450至500 nm的可见光发射。本工作旨在研究使用Pd-γ-AlO和PdO-γ-AlO NPs作为潜在光催化剂对有机染料污染物的光催化降解，包括溴甲酚绿（BCG）、溴百里酚蓝、亚甲基蓝和甲基橙。改变实验参数，包括有机染料溶液的进料浓度、Pd-γ-AlO和PdO-γ-AlO光催化剂用量以及pH值，以确定光催化降解的有利条件。结果表明，与其他有机染料相比，有机染料BCG在紫外光下在水溶液中完全（100%）降解。此外，Pd-γ-AlO NPs表现出比PdO-γ-AlO NPs更好的光催化性能。提出了Pd-γ-AlO和PdO-γ-AlO光催化剂对有机染料可能的光催化降解机理。研究表明，锚定在γ-AlO表面的Pd和PdO NPs是用于光催化降解有机染料的有前景且有效的催化剂。
