Perovskites as Catalysts in Advanced Oxidation Processes for Wastewater Treatment

Abstract

Advanced oxidation processes (AOPs), based on the formation of highly reactive radicals are able to degrade many organic contaminants present in effluent water. In the heterogeneous AOPS the presence of a solid which acts as catalyst in combination with other systems (O3, H2O2, light) is required. Among the different materials that can catalyse these processes, perovskites are found to be very promising, because they are highly stable and exhibit a high mobility of network oxygen with the possibility of forming vacancies and to stabilize unusual oxidation states of metals. In this review, we show the fundaments of different kinds of AOPs and the application of perovskite type oxides in them, classified attending to the oxidant used, ozone, H2O2 or peroxymonosulfate, alone or in combination with other systems. The photocatalytic oxidation, consisting in the activation of the perovskite by irradiation with ultraviolet or visible light is also revised.

Progress of Exsolved Metal Nanoparticles on Oxides as High Performance (Electro)Catalysts for the Conversion of Small Molecules

“…Perovskite‐based oxides recently gained great attention in this field because of their good catalytic activity. [ 260–263 ] Exsolution materials with perovskite‐based oxide matrices and surface metal nanoparticles can possibly activate new reaction pathways for the oxidation of pollutants in liquid environments.…”

Perovskite synthesis, properties and their related biochemical and industrial application

“…Generally, CMR effect is closely related to its manganites which are correlated electron systems with interplay among the lattice spin, Jahn-Taller effect, charge & orbital degrees of freedom, electronic phase separation, charge ordering, etc. (Rojas-Cervantes and Castillejos, 2019).…”

Perovskite Structure Associated with Precious Metals: Influence on Heterogenous Catalytic Process

“…Complex oxides systems-such as perovskite-based photocatalysts-emerge as an interesting alternative to photocatalytic processes [39][40][41]. Among the different advantages of the photophysical properties of perovskite, we can highlight: (i) their structures can be formed from a wide variety of elements, although their basic structures are similar; (ii) their valency, stoichiometry, and vacancy can be easily changed from the simple and non-laborious proceedings; (iii) possibility of a satisfactory prediction of their surface properties since their bulk structures are very well characterized; (iv) their crystal structures generally provide an appropriate electronic structure that shifts the band gap energy to visible-light absorption; (v) their crystal structural arrangements allow lattice distortions, strongly affecting the separation of photogenerated charge carriers and avoiding the recombination processes [41,42]. Therefore, the possibility of controlling the physical-chemical properties of perovskite structures allows unraveling the relationship between structural properties and photocatalytic activity, which makes this material a good photocatalyst alternative to TiO 2 [42].…”