Solar photocatalytic application of NbO_2OH as alternative photocatalyst for water treatment

摘要

Water recycling and industrial effluents remediation are a hot topic of research to reduce the environmental impact of the human activity. Persistent organic pollutants are highly recalcitrant compounds with hazardous effects associated to their fate in water bodies. Several novel technologies have been developed during the last decades to deal with this novel contamination. However, the natural sources and idiosyncrasy of each country lead to the potential application of different technologies. In this context, we have focused on the development of phocotalytic treatment of solutions containing dyes using a novel photocatalytic material, the Nb020H. The Nb020H was synthesized and characterized with different techniques. Several assays demonstrated the solar photoactivity of this novel oxyhydroxide catalyst, achieving complete decolorizations after 10 min of treatment under optimal conditions of 1.0 g L~(-1) Nb020H photocatalyst loading, 0.1 Μ of H_20_2 as electron scavenger, pH 4.0 and methyl orange concentrations up to 15 mg L~(-1). Also, the catalyst recuperation demonstrated the potential reuse of this photocatalyst without losing catalytic response after five cycles. This work is of significant importance because niobium is a natural resource, mainly extracted in Brazil and the annual global sunlight irradiation in the near-equatorial region of northeast Brazil is over the average solar irradiation of the planet. Thus, the solar photocatalytic treatment using NbO_2OH in northeast Brazil appears as a highly potential environmental-friendly nanotechnology to mitigate the water pollution.