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This work focuses on the microwave enhanced catalytic degradation of methyl orange (MO) in aqueous solution over CuO/CeO2 catalyst in the absence and presence of H2O2. The prepared CuO/CeO2 catalysts were characterized with X-ray diffraction, Brunnauer-Emmett-Teller analysis, temperature-programmed reduction, and temperature-programmed desorption techniques to elucidate the effect of calcination temperature on its properties and catalytic performance. The results show that calcination temperature exerts remarkable influence on the catalytic performance of CuO/CeO2, with that calcined at 300 °C displaying the highest MO degradation ability. On the basis of Fourier transform infrared spectroscopy, ultraviolet–visible spectroscopy, and X-ray photoelectron spectroscopy measurement results, the mechanism of MO degradation under microwave irradiation in the presence of both CuO/CeO2 and H2O2 was suggested. A synergistic rather than additive effect of catalyst, microwave irradiation, and H2O2 contributes to the high degradation activity toward MO.

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In this work, the graft copolymerization of acrylamide (AM) and methacryloyloxy ethyl trimethyl ammonium chloride (DMC) with the hemicellulose in the alkaline peroxide mechanical pulping (APMP) effluent was investigated using the Fenton agent (FeSO 4 /H 2 O 2 ) as an initiator. The effects of the reaction conditions on the characteristics of the graft copolymers were studied. On the basis of the graft copolymer characterization, the optimum conditions were as follows: total active ingredient concentration 31%, reactive temperature 50°C, amount of the initiator 0.4%, ratio of H 2 O 2 to FeSO 4 1:1, molar ratio of DMC to AM 1.5:20 and optimum percentages of C, G, GE, and viscosity are 65%, 246%, 98%, and 5020 cP, respectively. Structure elucidation of the graft copolymer was obtained by 1 H NMR spectroscopy and FT-IR. Gel-permeation chromatography (GPC) was employed to determine the molecular mass and molecular mass distribution of hemicellulose and graft copolymer. The thermal degradation properties of hemicellulose and the graft copolymers were measured by thermo gravimetric analysis (TGA). The graft copolymer was subsequently used as a corrugated paper surface sizing agent, which can significantly improve the physical strength and water resistance of corrugated paper.

Perovskite solar cells (PSCs) are attracting a tremendous attention from the scientific community due to their excellent power conversion efficiency, low cost, and great promise for the future of solar energy. The best PSCs have already achieved a certified power conversion efficiency (PCE) of 25.5 % after an unprecedented rapid performance rise. However, high requirements with respect to large area, high‐efficiency devices, and stability are still the challenges. Major efforts, especially for achieving a high degree of chemical control, have been made to reach these targets. The use of halide additives has played a critical role in improving the efficiency and stability. The present paper reviews the important breakthroughs in PSC technologies made by using halide additives, especially chloride, and pseudo‐halide additives for the preparation of the perovskite layers, other layers, and interfaces of the devices. These additives help perovskite (PVK) crystallization and layer morphology control, grain boundary reduction, bulk and interface defects passivation, and so on. Normally, these halide additives play different roles depending on their categories and their location. Herein, recent progresses made due to additives employment in every possible layer of PSCs are reviewed, with focus on chloride, other halides, and pseudo‐halides as additives in PVK films, halide additives in carrier transport layers, and at PVK‐contact interfaces. Finally, an outlook of engineering of these additives in PSC progress is given.

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