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A multifunctional, multiphase-supported photocatalyst was fabricated via the combination of LCD three-dimensional (3D) printing, cold plasma discharge (CPD) technology, and surface chemistry to be used for the degradation of organic pollutants in water and for the generation of hydrogen gas. BiOBr was chosen as the main catalytic phase and was used in association with a phosphor, SrAl2O4:Eu2+,Dy3+ (SAED), and a metal–organic framework, Ni-BDC. Their immobilization was realized thanks to polydopamine (PDA), which is used as a coupling agent. While BiOBr was the most active photocatalytic phase, the phosphor acted as a light-storing component for photodegradation in the dark and overall, as a boost for photoactivity. PDA also boosted the photoactivity, in parallel with its crucial role in the immobilization of the SAED/Ni-MOF/BiOBr catalyst on fractal polymer support. An in situ complexation-assisted precipitation (ISCAP) process was used, allowing the formation of the catalytic phases with nano features. The resulting hybrid photocatalysts were tested through rhodamine B (RhB) dye photodegradation upon visible light irradiation or light/dark alternating conditions to simulate more realistic variable light illumination. We found that, although used in a very small amount, the Ni-MOF had a significant impact on the photoactivity, forming a Z-scheme heterojunction with BiOBr. Finally, H2 evolution testing further established the photocatalytic activity and versatility of the supported catalysts. [ABSTRACT FROM AUTHOR]

In this paper, the sol-gel method was used to synthesize powders of LaMnO3 (LMO), La0.85Ca0.15MnO3 (LCM), and La0.85Sr0.15MnO3 (LSM). The effect of substituting Ca and Sr at the A-site on the perovskite crystal structure and electrochemical capabilities of LMO was investigated. LCM retained its orthogonal structure in comparison to the parent LMO components, whereas LSM transitioned to a rhombic structure. At 0.5 A/g, the specific capacitance of LCM and LSM electrodes is 185.5 F/g and 248 F/g, respectively. The specific capacitance of LCM was three times greater than that of the LMO electrode. Among the three samples (LMO, 22.25 m2 g−1; LSM, 31.56 m2 g−1), the LCM sample exhibited the highest specific surface area of 38.79 m2 g−1. The charge transfer resistances of the LMO, LCM, and LSM are 0.48 Ω, 0.36 Ω, and 0.38 Ω, respectively. The LCM electrode exhibits the greatest capacitance performance due to its more refined morphology, increased concentration of oxygen vacancy, and more complete utilization of the perovskite bulk structure. The above results demonstrate that Ca or Sr substitution of A-site compounds has great potential for supercapacitor applications. [ABSTRACT FROM AUTHOR]