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Solar photothermo-catalysis is a fascinating multi-catalytic approach for volatile organic compounds (VOCs) removal. In this work, we have explored the performance and the chemico-physical features of non-critical, noble, metal-free MnOx-ZrO2 mixed oxides. The structural, morphological, and optical characterizations of these materials pointed to as a low amount of ZrO2 favoured a good interaction and the ionic exchange between the Mn and the Zr ions. This favoured the redox properties of MnOx increasing the mobility of its oxygens that can participate in the VOCs oxidation through a Mars-van Krevelen mechanism. The further application of solar irradiation sped up the oxidation reactions promoting the VOCs total oxidation to CO2. The MnOx-5 wt.%ZrO2 sample showed, in the photothermo-catalytic tests, a toluene T90 (temperature of 90% of conversion) of 180 °C and an ethanol T90 conversion to CO2 of 156 °C, 36 °C, and 205 °C lower compared to the thermocatalytic tests, respectively. Finally, the same sample exhibited 84% toluene conversion and the best selectivity to CO2 in the ethanol removal after 5 h of solar irradiation at room temperature, a photoactivity similar to the most employed TiO2-based materials. The as-synthetized mixed oxide is promising for an improved sustainability in both catalyst design and environmental applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • A versatile spray-coating deposition produced CsPbBr 3 films on several substrates. • The synthetic procedure is a green process using non-toxic solvents. • Mild conditions, room T and ambient P are the key advantages of this approach. Recently, the all-inorganic halide perovskites have attracted great attention due to their unique optical properties, which make them appealing, if available in form of films, for application in different devices, such as photodetectors, catalysis, or energy conversion systems like solar cells. We report a facile, one-step approach using the β-diketonate metal − organic precursors, [Pb(hfa) 2 diglyme] 2 and Cs(hfa) to obtain CsPbBr 3 halide perovskite microcrystals. The CsPbBr 3 suspension in ethanol has been deposited on a wide range of rigid and flexible substrates by spray-coating. The entire process has been carried out at room temperature and at atmospheric pressure in air. The X-ray diffraction (XRD) and Energy Dispersive X-ray analysis (EDX) confirmed the formation of pure stoichiometric CsPbBr 3 phase films, while the field-emission scanning electron microscopy (FE-SEM) indicates the growth of a compact and homogeneous layer independently on the substrate nature. The optical energy band-gap (E g) of CsPbBr 3 films on quartz, estimated through the Tauc equation, is equal to 2.31 eV. Steady state Photoluminescence (PL), Time Resolved Photoluminescence (TRPL), and Photoluminescence Quantum Yield (PLQY) investigations have been carried out confirming the quality of the films in agreement with literature. This synthetic approach allows the fabrication of perovskite CsPbBr 3 films on a variety of substrates, as well as providing a proof-of-concept method to extend this simple, practical, and versatile route for the production of mixed halide perovskite phases. [ABSTRACT FROM AUTHOR]