Reactive ball-milling synthesis of Co-Fe bimetallic catalyst for efficient hydrogenation of carbon dioxide to value-added hydrocarbons

Catalytic hydrogenation of CO_(2) using renewable hydrogen not only reduces greenhouse gas emissions,but also provides industrial chemicals.Herein,a Co-Fe bimetallic catalyst was developed by a facile reactive ball-milling method for highly active and selective hydrogenation of CO_(2) to value-added hydrocarbons.When reacted at 320℃,1.0 MPa and 9600 mL h^(-1) g_(cat)^(-1),the selectivity to light olefin(C_(2)^(=)-C_(4)^(=)) and C_(5)+ species achieves 57.3% and 22.3%,respectively,at a CO_(2) co nversion of 31.4%,which is superior to previous Fe-based catalysts.The CO_(2) activation can be promoted by the CoFe phase formed by reactive ball milling of the Fe-Co_(3)O_(4) mixture,and the in-situ Co_(2)C and Fe_(5)C_(2) formed during hydrogenation are beneficial for the C-C coupling reaction.The initial C-C coupling is related to the combination of CO species with the surface carbon of Fe/Co carbides,and the sustained C-C coupling is maintained by self-recovery of defective carbides.This new strategy contributes to the development of efficient catalysts for the hydrogenation of CO_(2) to value-added hydrocarbons.

An anthraquinone-based Cu(I) cyclic trinuclear complex for photo-catalyzing C–C coupling reactions

Development of transition metal-based photocatalysts with low cost, strong visible light absorption, and high efficiency is a longstand pursuit for advanced organic synthesis, yet remains highly challenging. In this article, an anthraquinone-based copper(I)cyclic trinuclear complex(1) was designed and it featured strong visible light absorption, high charge separation efficiency and photochemical properties. Complex 1 as a heterogeneous photocatalyst can efficiently catalyze homo-coupling of terminal alkynes and denitrification-oxidative coupling reaction between hydrazinopyridine and terminal alkynes with excellent yield(up to 99%), broad substrate tolerance(27 examples) and superior reusability(up to 10 cycles without loss of performance) under mild conditions.

Plasmonic coupling-enhanced in situ photothermal nanoreactor with shape selective catalysis for C–C coupling reaction

Carbon-carbon(C–C)coupling reactions represent one of the most powerful tools for the synthesis of complex natural products,bioactive molecules developed as drugs and agrochemicals.In this work,a multifunctional nanoreactor for C–C coupling reaction was successfully fabricated via encapsulating the core-shell Cu@Ni nanocubes into ZIF-8(Cu@Ni@ZIF-8).In this nanoreactor,Ni shell of the core-shell Cu@Ni nanocubes was the catalytical active center,and Cu core was in situ heating source for the catalyst by absorbing the visible light.Moreover,benefiting from the plasmonic resonance effect between Cu@Ni nanocubes encapsulated in ZIF-8,the absorption range of nanoreactor was widened and the utilization rate of visible light was enhanced.Most importantly,the microporous structure of ZIF-8 provided shape-selective of reactant.This composite was used for the highly shape-selective and stable photocatalysed C–C coupling reaction of boric acid under visible light irradiation.After five cycles,the nanoreactor still remained high catalytical activity.This Cu@Ni@ZIF-8 nanoreactor opens a way for photocatalytic C–C coupling reactions with shape-selectivity.