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The electrochemical fixation of carbon dioxide (CO2) into organic halides is one of the most prominent strategies for mitigating atmospheric CO2 emission, along with the difficulties associated with the toxic and carcinogenic halogenated compounds. Cu-based nanomaterials have been explored for numerous applications in nanotechnology, including electrocatalysis, organic catalytic transformations, and photocatalysis. In this work, we have designed and developed a Cu-embedded carbazole-derived porous organic polymer (Cu@Cz-POP) nanohybrid by utilizing the Friedel–Crafts alkylation approach and employing 1,4-dimethoxybenzene as the cross-linking agent comprising unique characteristic features of the extended π-conjugated system along with an active metal center with tunable electrochemical properties. The Brunauer–Emmett–Teller surface area of the conjugated Cz-POP is found to be 1060 m2 g–1. The X-ray photoelectron spectroscopy (XPS) study demonstrates the formation of CuO nanoparticles in the polymeric framework. X-ray absorption fine structure analysis (EXAFS) also reveals the existence of CuO with a smaller fraction of Cu in the polymeric framework, which is corroborated with the XPS analysis. The Cu@Cz-POP nanohybrid is fabricated by drop-casting over a Ni foam, showing promising electrocatalytic activity toward electrocarboxylation of benzyl bromide in 0.1 M TBA·BF4/CH3CN with saturated CO2 medium with a current density of 120 mA cm–2 delivering 65% yield of phenylacetic acid (PAA) as the primary product along with traces of benzyl 2-phenylacetate (BPA) and 1,2-diphenylethane (DPE), and the turnover frequency is found to be 8.556 × 10–7 s–1. Density functional theory calculations demonstrate that CuO is adsorbed more favorably at the N1 nitrogen atom of Cz-POP. An electron transfer from the N1 atom and the aromatic rings of Cz-POP to the CuO center is observed and confirmed by the overlap of alpha orbitals. [ABSTRACT FROM AUTHOR]

Using a catalyst-free one-pot polycondensation approach, a new donor–acceptor (D–A) based porous polyimide (PeTt–POP) photocatalyst was developed. PeTt–POP produced CH4 (125.63 ppm g−1 in 6 h) from CO2 under visible light irradiation in the gas–solid mode without the use of co-catalysts or sacrificial agents. The progress of the reaction and the corresponding intermediate species involved in the CO2 reduction were identified by operando DRIFTS experiments, from which a plausible reaction mechanism was proposed. [ABSTRACT FROM AUTHOR]

Hydrothermal synthesis of a ZSM-5/MCM-41 composite has been carried out from pre-synthesized ZSM-5 zeolite as a silica source and CTAB as a template. The ZSM-5/MCM-41 composite materials were further loaded with varying wt% of cobalt with respect to ZSM-5 by an in situ modification method using cobaltous nitrate as a metal source. Detailed analysis of the synthesized materials was performed using different characterization techniques such as PXRD, FT-IR, TGA, UV-Vis DRS, N2 adsorption–desorption and SEM-EDX. The catalytic activity of the synthesized materials for liquid phase oxidation of diphenylmethane was investigated in the presence of 70% TBHP as an oxidant where benzophenone was obtained as a major product. The effects of various reaction parameters were studied to perceive the conversion of diphenylmethane and enhance the selectivity towards benzophenone. [ABSTRACT FROM AUTHOR]

Functionalization of synthesized mesoporous MCM‐48 was performed using phosphoric acid via post synthesis modification method and characterized using different analytical techniques. The acidic character of the phosphoric acid modified material was enhanced compared to parent MCM‐48 as predicted from the Ammonia‐Temperature Programmed Desorption (NH3‐TPD) analysis. The catalytic activity of the synthesized materials was investigated for the synthesis of 2‐amino‐4H‐chromene via one pot three component reaction using aldehyde, malononitrile and dimedone using ethanol as solvent at 60 °C. Moderate to good yields of the desired products were obtained with substituted benzaldehyde under the optimized reaction condition. Moreover, reusability of the catalyst was also demonstrated upto five catalytic cycles with minimal loss in catalytic activity. [ABSTRACT FROM AUTHOR]

Using a catalyst-free one-pot polycondensation approach, a new donor-acceptor (D-A) based porous polyimide (PeTt-POP) photocatalyst was developed. PeTt-POP produced CH 4 (125.63 ppm g -1 in 6 h) from CO 2 under visible light irradiation in the gas-solid mode without the use of co-catalysts or sacrificial agents. The progress of the reaction and the corresponding intermediate species involved in the CO 2 reduction were identified by operando DRIFTS experiments, from which a plausible reaction mechanism was proposed.