Cendrowski Krzysztof, Pachnowska Kamila, Augustyniak Adrian, Wierzbicka Jagoda, Pratnicki Filip, Kucharski Pawel, Kukułka Wojciech, Mijowska Ewa
Department of Nanomaterials Physicochemistry, Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology, Szczecin, Al. Piastów 45, Szczecin 70-311, Poland.
Faculty of Civil and Environmental Engineering, West Pomeranian University of Technology, Szczecin, Al Piastów 50a, Szczecin 70-311, Poland.
Nanotechnology. 2021 May 10;32(31). doi: 10.1088/1361-6528/abf9c5.
In this study, the core-shell silica nanospheres modified with titanium dioxide were tested in the photocatalytic decomposition of dyes. The presented data underlines the advantages and shortcomings in the potential application of silica-based catalysts to neutralize organic pollutants. During the photocatalytic reaction in distilled water, catalysts showed decreased efficiency due to a carbon layer deposited on its surface. This finding set an additional goal to investigate the possibility of regenerating the photocatalyst. Studies have shown that the catalyst could be successfully reused following the thermal removal of deposited carbon.Furthermore, the reactivated silica-titania catalysts exhibited comparable photocatalytic performance to the newly made nanomaterial. Surprisingly, catalyst application in the river water eventually resulted in the permanent deactivation of silica-titania nanospheres, which was caused by the interchangeable silica dissolution/precipitation process on the surface of the studied nanomaterial. In environmental water, silica dissolves and precipitates on titanium dioxide's surface, blocking the interaction between organic compounds and TiO. The deactivation occurring in the environmental samples is irreversible. In distilled water, the decomposition of organic compounds leads to photocatalysts' deactivation by forming a carbon layer on their surface. Reactivation of the silica-based photocatalyst after distilled water is achievable by annealing at a high temperature. In light of our findings, the combination of the photocatalytic properties of TiOand the silica template shows no prospects in the purification of polluted waste or environmental water.
在本研究中，对用二氧化钛改性的核壳二氧化硅纳米球进行了染料光催化分解测试。所呈现的数据突显了基于二氧化硅的催化剂在中和有机污染物潜在应用中的优缺点。在蒸馏水中进行光催化反应时，催化剂由于其表面沉积的碳层而效率降低。这一发现设定了一个额外目标，即研究光催化剂再生的可能性。研究表明，通过热去除沉积的碳，催化剂可以成功再利用。此外，再活化的二氧化硅 - 二氧化钛催化剂表现出与新制备的纳米材料相当的光催化性能。令人惊讶的是，在河水中应用催化剂最终导致二氧化硅 - 二氧化钛纳米球永久失活，这是由所研究纳米材料表面可互换的二氧化硅溶解/沉淀过程引起的。在环境水中，二氧化硅在二氧化钛表面溶解和沉淀，阻碍了有机化合物与二氧化钛之间的相互作用。环境样品中发生的失活是不可逆的。在蒸馏水中，有机化合物的分解通过在光催化剂表面形成碳层导致其失活。通过高温退火可实现蒸馏水中基于二氧化硅的光催化剂的再活化。根据我们的研究结果，二氧化钛的光催化性能与二氧化硅模板的结合在净化污染废物或环境水方面没有前景。
