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Defect-promoted dual-functional reaction system : a cetyltrimethylammonium bromide (CTAB) functionalized ZnIn 2 S 4 (defectived ZIS)-based dual-functional reaction system enables efficient visible light-driven CO 2 -to-CO conversion and simultaneous selective oxidation of benzyl alcohol (BA) to C C coupled products in a cooperative photoredox manner. • A dual-functional reaction pairing CO 2 reduction and oxidative organic synthesis. • Structure distorted CTAB-ZIS fabricated by a CTAB assisted hydrothermal process. • Defect structure of CTAB-ZIS favors oxidation of BA to C C coupled products. Pairing CO 2 reduction with oxidative organic synthesis in one photoredox cycle opens a new avenue for cooperative utilization of excited electrons and holes towards efficient solar-to-chemical energy conversion. In this work, we demonstrate a facile cetyltrimethylammonium bromide (CTAB) surfactant functionalized ZnIn 2 S 4 (ZIS)-based dual-functional reaction system for efficient visible light-driven CO 2 -to-CO conversion pairing with selective oxidation of benzyl alcohol to value-added C C coupled products. Our research suggests that the markedly enhanced redox activities are mainly attributed to the unique structure of CTAB-ZIS featuring more crystalline and surface defects, which greatly promotes the interfacial charge carrier transfer, and in particular elevates CO 2 activation and electrons reducibility. It is anticipated that this work would inspire further establishment of efficient novel photocatalysts and cooperative reaction system coupling CO 2 reduction and organic synthesis in a cost-effective manner under ambient conditions to meet the economic and social sustainability goals. [ABSTRACT FROM AUTHOR]

Graphical abstract This paper describes core-shell cobalt-manganese oxides with specific morphologies and oxygen vacancies for electrochemical water oxidation. Highlights • A new preparation method with facet modulation of Mn@CoMnO nanoparticles is developed. • Octahedral truncated octahedral, and cubic structures of nanoparticles NPs are successfully synthesized. • The correlation between structure and electrochemical water oxidation properties is proposed. • Exposed octahedral active cation and enhanced charge-transfer ability are important. Abstract Developing efficient and stable non-noble electrocatalysts for oxygen evolution reaction (OER) is one of the promising and challenging issues. This paper describes an approach to prepare core-shell cobalt-manganese oxides with specific morphologies and oxygen vacancies. Via a facile seed growth method, facets evolution is achieved during the formation of core-shell structure. Benefited from optimized surface environment, oxygen vacancy-enriched octahedral cobalt-manganese oxides supported on Ni foam exhibited relatively low overpotential of 284 mV at the current density of 10 mA cm−2 and diminutive tafel slope of 73.1 mV dec−1 as well as long-term stability. This work successfully unveils a method for facet-modulation of core-shell metal oxides as efficient electrochemical OER catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • The multimodal optical excitation pulsed thermography can enhance the depth-resolution dynamic range for debonding defects of the solid propellant rocket motor. • Multiple feature extraction algorithms were proposed and applied to extract characteristic parameters. • Pulse thermography optimized by PLSR and ICA can achieve better detection of interface debonding defects. We demonstrated the multimodal optical excitation pulsed thermography, and this technique can enhance the defect detectability and the depth-resolution dynamic range for the propellant /cladding layer interface debonding defects of the solid propellant rocket motor. Firstly, three-dimensional (3D) thermal-wave model which stimulated by a pulse excitation thermal source was built. The temperature field distribution and the thermal-wave diffusion behavior were analyzed. Subsequently, multiple feature extraction algorithms were proposed and applied to extract characteristic images. The experimental set-up was developed and utilized to detect cladding layers with artificial defects. The results demonstrate that pulse thermography optimized by PLSR and ICA can achieve better detection of interface debonding defects. The characteristic profiles were analyzed to evaluate the ability of feature images to characterize the defect diameter and depth. The results depict that the 1st independent component has a better detection effect for defect depth and diameter. [ABSTRACT FROM AUTHOR]

Abstract: The long-term stability and activity of catalysts are vital for vapor-phase selective hydrogenation of dimethyl oxalate to synthesize ethanol. Boron has been widely employed as a modifier for transition-metal catalysts mainly to, improve selectivity and stability. We introduced boron species by impregnation into silica-supported copper catalysts prepared by an ammonia evaporation hydrothermal method and investigated their catalytic activity and thermal stability for hydrogenation of dimethyl oxalate. The effect on activity mainly depends on the amount of boron and an optimal Cu/B molar ratio of 3 was obtained. The characterization of the catalysts shows that boron-modified Cu/SiO2 facilitates the dispersion of copper species, enhances the metal–support interaction, and suppresses the growth of copper particles during dimethyl oxalate hydrogenation. [Copyright &y& Elsevier]