Peroxymonosulfate-assisted photocatalytic degradation of rhodamine B by g-C 3 N 4 nanoparticles modified with NiO cubes

AbstractHerein, NiO cubes with {100} facets or NiO trapezohedrons with {311} facets modified graphite carbon nitride (g-C3N4) nanoparticles acidified by HCl (HCN) were fabricated to form a p-n heterojunction (NiO/HCN) for the first time. These were further used for the degradation of rhodamine B (RhB) in water. 8-{100}NiO/HCN exhibited the highest degradation efficiency of 98.56% in just 60 min within peroxymonosulfate (PMS) under visible light. It was 2.51% higher than that of 8-{311} NiO/HCN. A series of characterization and experimental results showed that introducing {100} NiO could improve both the photocatalysis and PMS activation efficiency of the g-C3N4 compared with {311} NiO. The influence of environmental parameters on RhB degradation was systematically studied as well. Stability experiments demonstrated that 8-{100}NiO/HCN maintained high catalytic performance over a period of 10 h. The degradation mechanism behind PMS activation under visible light involved several factors: the unique micron-nano interface structure, electron (e-) transfer between NiO and g-C3N4, as well as effective facilitation of PMS activation by Ni2+. These factors led to the formation of singlet oxygen (1O2), which contributed significantly to RhB degradation. Overall, this work highlights how facet design can be utilized in metal oxide cocatalysts to improve photocatalytic degradation performance.Keywords: {100}NiO/HCNcarbon nitridefacet engineeringphotocatalysisperoxymonosulfate Disclosure statementThe authors report there are no competing interests to declare.Additional informationFundingThis work was supported by the Sichuan Changhong Electronic Holding Group Co., Ltd., Chengdu, China.