Photoactive Heterostructures Based on α-Fe₂O₃ and CuO Thin Films for the Removal of Pollutants from Aqueous Solutions

Abstract

Heterostructured photoactive nanomaterials represent innovative construction to absorb UV and UV-vis light. This feature makes heterostructures exciting candidates for environmental photocatalytic applications such as organic pollutants degradation and removal of heavy metals, among others. Therefore, the efficient design of heterostructures based on thin films of oxide semiconductors will allow obtaining a novel material with outstanding properties. This work presents a review of the current heterostructures based on α-Fe2O3 and CuO thin films, which were deposited onto different substrates using physics and chemistry routes. Moreover, we will discuss the key factors to promote structural and morphology control and the drawbacks such as low absorption of the solar spectra, low active surface area, and charge carrier recombination. Finally, the relevance of the results and future directions of the heterostructures as materials for the purification of aqueous systems were discussed.