Heterogeneous photocatalysis has been considered as one of the most attractive alternative routes to transform naturally abundant, clean, and sustainable solar energy into chemical energy. Considering efficient solar-energy utilisation, the development of new materials that are sensitive to visible light is an important direction in the theory and practice of heterogeneous photocatalysis. In recent years, many efforts have been focused on the development of pyrochlore oxides as visible light-responsive photocatalysts for the degradation of dyes, water splitting, and CO₂ reduction. The interest in pyrochlores is attributed to their compositional flexibility to manipulate the electron/hole mobility by introducing a wide range of elements into their structure. The present perspective reports the progress over the last 5 years in the use of pyrochlore-like oxides as promising photocatalysts for various applications. A special focus of this perspective is on the strategies for the enhancement of the photocatalytic activity of pyrochlores, namely optimisation of their preparation method, band gap engineering, incorporation of plasmonic metals, and creation of heterojunctions.

Zinc oxide nanoparticles were obtained by plasma-enhanced chemical vapor deposition (PECVD) under optical emission spectrometry control from elemental high-purity zinc in a zinc–oxygen–hydrogen plasma-forming gas mixture with varying deposition parameters: a zinc source temperature, and a reactor temperature in a deposition zone. The size and morphological parameters of the zinc oxide nanopowders, structural properties, and homogeneity were studied. The study was carried out with use of methods such as scanning electron microscopy, X-ray structural analysis, and Raman spectroscopy, as well as statistical methods for processing and analyzing experimental data. It was established that to obtain zinc oxide nanoparticles with a given size and morphological characteristics using PECVD, it is necessary (1) to increase the zinc source temperature to synthesize more elongated structures in one direction (and vice versa), and (2) to decrease the reactor temperature in the deposition zone to reduce the transverse size of the deposited structures (and vice versa), taking into account that at relatively low temperatures instead of powder structures, films can form.