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Electrocatalytic CO2 reduction is a typical reaction involving two reactants (CO2 and H2O). However, the role of H2O dissociation, which provides active *H species to multiple protonation steps, is usually overlooked. Herein, we construct a dual-active sites catalyst comprising atomic Cu sites and Cu nanoparticles supported on N-doped carbon matrix. Efficient electrosynthesis of multi-carbon products is achieved with Faradaic efficiency approaching 75.4% with a partial current density of 289.2 mA cm−2 at −0.6 V. Experimental and theoretical studies reveal that Cu nanoparticles facilitate the C-C coupling step through *CHO dimerization, while the atomic Cu sites boost H2O dissociation to form *H. The generated *H migrate to Cu nanoparticles and modulate the *H coverage on Cu NPs, and thus promote *CO-to-*CHO. The dual-active sites effect of Cu single-sites and Cu nanoparticles gives rise to the catalytic performance. A dual-site catalyst consisting of Cu nanoparticles (NPs) and atomic Cu sites is designed. The atomic Cu boosts H2O dissociation for modulating the *H coverage on Cu NPs, improving the efficiency of CO2 electroreduction to multi-carbon products. [ABSTRACT FROM AUTHOR]

Effective valorization of lignin to produce high-value chemical products can enhance the productivity and profitability of biorefineries. The upgrading of lignin derived molecules such as phenols into high-value commodity chemicals is an effective way to combine low environmental footprint with significant economic benefits. Selective O-acylation of phenolic compounds to produce phenolic esters which possess diverse applications is very attractive. Herein, we report an efficient, convenient one-pot method for selective O-acylation of phenols at room temperature in air. For the first time, abundant, safe, stable organic salts are used as acylating reagents. The reaction was mediated by diethylaminosulfur trifluoride (DAST) which simultaneously acted as an activator for phenols and deoxyfluorination reagent for organic salts. Phenolic esters were almost quantitatively produced from a diverse range of phenols including lignin-derived substrates. This new method is significantly distinct from existing routes, and the scientific discovery about activation of phenolic hydroxyl groups is instructive for exploration of new chemical reactions. [ABSTRACT FROM AUTHOR]

It is very interesting to synthesize high value-added chemicals from CO2 under mild conditions with low energy consumption. Here, we report that a novel catalyst, Zn(betaine)2Br2, can efficiently promote the cycloaddition of CO2 with epoxides to synthesize cyclic carbonates under ambient conditions (30 °C, 1 atm). DFT calculations provide important insights into the mechanism, particularly the unusual synergistic catalytic action of Zn2+, Br− and NR4+, which is the critical factor for the outstanding performance of Zn(betaine)2Br2. The unique features of the catalyst are that it is cheap, green and very easy to prepare. [ABSTRACT FROM AUTHOR]

Electrochemical reaction of CO2 and water to produce valuable chemicals and fuels is of great importance. Producing syngas with tunable CO/H2 ratios and high current density is an interesting topic. In this work, Zn films with different morphologies and wettability were fabricated. It was demonstrated that Zn films could be used as efficient electrocatalysts for CO2 reduction to syngas and the CO/H2 ratios could be controlled in the range of 0.09–11.4 changing the morphology and wettability of the catalysts and the applied potential. Particularly, using the nanoleaf Zn film with a water contact angle of 91° as the electrode, the current density could reach 90.4 mA cm−2 with a CO/H2 ratio of 1/1 at −1.27 V vs. RHE. In addition, the maximum FE of CO could reach 92.6% with a current density of 35.3 mA cm−2 at a low overpotential of 440 mV. Detailed studies reveal that the three-dimensional electrode architecture and suitable wettability were favorable for CO2/H+ mass transfer and charge transfer, which are important factors for achieving efficiency. [ABSTRACT FROM AUTHOR]

Co nanoparticles supported on N,B-co-doped graphitic carbon exhibited efficient electrocatalytic activity towards the transformation of CO2 to CO with a faradaic efficiency of 97.9% and a current density of 18.8 mA cm−2, which is the highest current density at high FE over Co-based catalysts in an H-cell. The ratio of CO to H2 can be adjusted by changing the amount of B doping. The excellent performance of the catalyst is mainly due to its favorable electron density configuration, larger electrochemical surface area, and higher conductivity. [ABSTRACT FROM AUTHOR]

Selective hydrogenolysis of biomass-derived furanic compounds is a promising approach for synthesizing aliphatic polyols by opening the furan ring. However, there remains a significant need for highly efficient catalysts that selectively target the Csp 2 -O bond in the furan ring, as well as for a deeper understanding of the fundamental atomistic mechanisms behind these reactions. In this study, we present the use of Pt-Fe bimetallic catalysts supported on layered double hydroxides [PtFe x /LDH] for the hydrogenolysis of furanic compounds into aliphatic alcohols, achieving over 90% selectivity toward diols and triols. Our findings reveal that the synergy between Pt nanoparticles, atomically dispersed Pt sites and the support facilitates the formation of hydride-proton pair at the Pt δ + ⋯O 2- Lewis acid-base unit of PtFe x /LDH through hydrogen spillover. The hydride specifically targets the Csp 2 -O bond in the furan ring, initiating an S N 2 reaction and ring cleavage. Moreover, the presence of Fe improves the yield of desired alcohols by inhibiting the adsorption of vinyl groups, thereby suppressing the hydrogenation of the furan ring., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Urea electrosynthesis under ambient conditions is emerging as a promising alternative to conventional synthetic protocols. However, the weak binding of reactants/intermediates on the catalyst surface induces multiple competing pathways, hindering efficient urea production. Herein, we report the synthesis of defective Co 3 O 4 catalysts that integrate dual-functional sites for urea production from CO 2 and nitrite. Regulating the reactant adsorption capacity on defective Co 3 O 4 catalysts can efficiently control the competing reaction pathways. The urea yield rate of 3361 mg h -1 g cat -1 was achieved with a corresponding faradaic efficiency (FE) of 26.3% and 100% carbon selectivity at a potential of -0.7 V vs. the reversible hydrogen electrode. Both experimental and theoretical investigations reveal that the introduction of oxygen vacancies efficiently triggers the formation of well-matched adsorption/activation sites, optimizing the adsorption of reactants/intermediates while decreasing the C-N coupling reaction energy. This work offers new insights into the development of dual-functional catalysts based on non-noble transition metal oxides with oxygen vacancies, enabling the efficient electrosynthesis of essential C-N fine chemicals., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

It is very interesting to synthesize high value-added chemicals from CO 2 under mild conditions with low energy consumption. Here, we report that a novel catalyst, Zn(betaine) 2 Br 2 , can efficiently promote the cycloaddition of CO 2 with epoxides to synthesize cyclic carbonates under ambient conditions (30 °C, 1 atm). DFT calculations provide important insights into the mechanism, particularly the unusual synergistic catalytic action of Zn 2+ , Br - and NR 4+ , which is the critical factor for the outstanding performance of Zn(betaine) 2 Br 2 . The unique features of the catalyst are that it is cheap, green and very easy to prepare.