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The CO2 electrochemical reduction reaction (CO2ERR) is heralded for carbon dioxide and renewable energy utilization. However, complexities in catalyst optimization and reactor structure research hinder its practical application. Herein, rather than traditional catalyst optimization, emphasis is placed on refining the reactor structure to enhance gas–liquid mixing. The goal is to raise the CO2 concentration in the reaction zone and extend its residence refining CO2ERR. Building on prior reactor designs, this work introduces the N‐reactor (the nozzle‐type reactor) with a ring electrode suited for gas–liquid mixing and reaction interplay. Through finite element simulations using the gas–liquid flow model, compared with the S‐reactors (the wide‐straight‐type reactor and the narrow‐straight‐type reactor), the N‐reactor's ring electrode shows a 12.99% CO2 concentration rise in the electrode zone and a 67.11% surge at the cathode exit. As a consequence, the total concentration of the product methanol is increased by 6.37%, with a maximum concentration increase of 26.96% and a concentration increase of 49.08% at the cathode outlet. These results validate the feasibility of optimizing the reaction from the perspective of gas–liquid mixing flow and provide novel methods and ideas for further optimization of CO2ERR, contributing to the practical application of the technology. [ABSTRACT FROM AUTHOR]

Electrocatalytic conversion of waste nitric oxide into ammonia is a promising approach to achieve sustainable nitrogen fixation. Herein, a CoNi co‐oxides catalyst is designed for NH3 electrosynthesis with the merits of facilitating NO adsorption and reducing the reaction energy barrier. By synergistic coupling with anodic NO oxidation, electrocatalytic disproportionation of NO is first realized to simultaneously synthesize value‐added double nitrogen products (NH3 and nitrate) with increased total energy efficiency. Furthermore, decoupled acid–base asymmetric electrolyte design is proposed in a united assembled electrolyzer, enabling a high NH3 production rate (26.27 mg h−1 cm−2) with unit faradaic efficiency and a remarkable nitrate production rate of 68.41 mg h−1 cm−2 at the anode. A low cell voltage of 3.58 V is obtained by optimizing ion agglomeration within the membrane to promote the charge‐ion exchange and electrode kinetics. Technoeconomic analysis demonstrates the economic feasibility of recycling waste NO by the electrocatalytic disproportionation strategy. [ABSTRACT FROM AUTHOR]

An interconnected and hierarchically structured electrode composed of a Cu nanoparticle‐modified flower‐like reduced graphene oxide‐decorated copper foam (Cu NP/f‐RGO/CF) is crafted and exploited for photoelectrocatalytic (PEC) reduction of CO2 in a TiO2 nanotube photoanode‐driven PEC cell. Anode photovoltage compensation confers a more negative cathode potential for CO2 reduction, thus leading to a synergistic effect between photocatalysis (PC) and electrocatalysis (EC). CO2 reduction rate under PEC condition is 5.4× higher than that of the simple sum under PC and EC processes. The well‐defined flower structure of RGO in the CF scaffold effectively prevents its self‐agglomeration, which increases its adsorption towards CO2 with improved electron‐transfer kinetics due to the 3D interconnected structure with abundant electron transfer pathways. DFT calculations further reveal the absorption and activation of CO2 on Cu NP/f‐RGO capitalize on the CC bond with RGO and OCu bond with Cu NPs, thereby leading to a bended and stretched structure. The enhanced CO2 adsorptivity and activation on the hierarchical Cu NP/f‐RGO/CF electrode significantly improve CO2 reduction and facilitate the conversion of C1 products to high‐order products. This research highlights the great prospect of anode photovoltage compensation enables synergistic photoelectrocatalysis and 3D hierarchical electrode for CO2 drastic reduction into high‐order products. [ABSTRACT FROM AUTHOR]