In this research, the investigation of sensing properties of non-stoichiometric WO₃ (WO_3−x) film towards some volatile organic compounds (VOC) (namely: Methanol, ethanol, isopropanol, acetone) and ammonia gas are reported. Sensors were tested at several temperatures within the interval ranging from a relatively low temperature of 60 up to 270 °C. Significant variation of selectivity, which depended on the operational temperature of sensor, was observed. Here, the reported WO₃/WO_3–x-based sensing material opens an avenue for the design of sensors with temperature-dependent sensitivity, which can be applied in the design of new gas- and/or VOC-sensing systems that are dedicated for the determination of particular gas- and/or VOC-based analyte concentration in the mixture of different gases and/or VOCs, using multivariate analysis of variance (MANOVA).

Porous 3D Cu layers with the following average parameters: thickness ~35 µm, pore density ~4.0 × 10⁶ cm⁻², and pore sizes ~25 µm were electrodeposited from an acidic sulphate electrolyte, and the suitability of different electrochemically active surface area determination methods for characterising these electrodes was assessed. Structural characterisation of the samples was conducted using SEM and an optical profiler, while electrochemical measurements were performed using cyclic voltammetry and electrochemical impedance spectroscopy. The evaluation of electrochemically active surface area involved the underpotential deposition of Tl and Pb monolayers as well as double-layer capacitance measurements. The results obtained indicate that both methods yield similar results for non-porous Cu electrodes. However, for Cu 3D nanostructures, the evaluation mode significantly influences the results. Double-layer capacitance measurements show significantly higher values for the electrochemically active surface area compared to the underpotential deposition (UPD) technique. The complex spatial structure of the Cu 3D layer hinders the formation of a continuous monolayer during the UPD process, which is the principal reason for the observed differences.

Cesium-containing triple cation perovskites are attracting significant attention as suitable tandem partners for silicon solar cells. The perovskite layer of a solar cell must strongly absorb the visible light and be transparent to the infrared light. Optical transmittance measurements of perovskite layers containing different cesium concentrations (0–15%) were carried out on purpose to evaluate the utility of the layers for the fabrication of monolithic perovskite/silicon tandem solar cells. The transmittance of the layers weakly depended on cesium concentration in the infrared spectral range, and it was more than 0.55 at 997 nm wavelength. It was found that perovskite solar cells containing 10% of cesium concentration show maximum power conversion efficiency.

Performance of a perovskite solar cell is largely influenced by the optoelectronic properties of metal halide perovskite films. Here we study the influence of cesium concentration on morphology, crystal structure, photoluminescence and optical properties of the triple cation perovskite film. Incorporation of small amount (x = 0.1) of cesium cations into Cs_x(MA_0.17FA_0.83)_1−x Pb(I_0.83Br_0.17)₃ leads to enhanced power conversion efficiency (PCE) of the solar cell resulting mainly from significant rise of the short-current density and the fill factor value. Further increase of Cs concentration (x > 0.1) decreases the film’s phase purity, carrier lifetime and correspondingly reduces PCE of the solar cell. Higher concentration of Cs (x ≥ 0.2) causes phase segregation of the perovskite alongside with formation of Cs-rich regions impeding light absorption.

The high efficiency of perovskite solar cells strongly depends on the quality of perovskite films and carrier extraction layers. Here, we present the results of an investigation of the photoelectric properties of solar cells based on perovskite films grown on compact and mesoporous titanium dioxide layers. Kinetics of charge carrier transport and their extraction in triple-cation perovskite solar cells were studied by using transient photovoltage and time-resolved photoluminescence decay measurements. X-ray diffraction analysis revealed that the crystallinity of the perovskite films grown on mesoporous titanium dioxide is better compared to the films grown on compact TiO₂. Mesoporous structured perovskite solar cells are found to have higher power conversion efficiency mainly due to enlarged perovskite/mesoporous -TiO₂ interfacial area and better crystallinity of their perovskite films.

The enzymatic degradation of various solvent-based polyurethane adhesives by cutinase from Humicola insolens (HiC) is assessed.