Min Kuang

Cascade catalytic conversion of CO2 has recently emerged as a transformative strategy for multilevel CO2 valorization. By integration of electrocatalytic CO2 reduction with thermocatalytic and/or biocatalytic processes, this approach enables stepwise construction of complex products from simple carbon feedstocks. The electrocatalytic stage supplies key intermediates or upstream products such as CO, formate, formaldehyde, or ethanol, which can be further converted into value-added multicarbon products including sugars, polymers, and other fine chemicals through downstream coupling. Recent demonstrations, ranging from CO2-to-sugar and CO2-to-polyketone conversions to artificial CO2-to-polymer biocatalytic pathways, have demonstrated the great potential of cascade strategies in bridging electro-, thermo-, and biochemistry. This Outlook discusses recent progress in electrochemical cascade CO2 conversion and outlines the key design goals for this field, including full-cascade performances, coupled catalyst-reaction optimizations, mechanistic understanding across complex interfaces, and integrated reactor architectures.

Electrocatalysis provides a green and scalable route for synthesizing polymer monomers directly from renewable feedstocks such as water, CO₂, and biomass derivatives. This review delineates the evolution of electrocatalytic strategies, presenting a progressively advancing framework, from elementary transformations to integrated catalytic systems. The strategies discussed represent different stages of this evolution: (i) primary aqueous electrochemical transformations driven by in situ generated *H or ⁻OH species for producing monomers such as adipic acid, lactic acid, and ethylene; (ii) coupling electrocatalytic transformations, in which electrochemically generated electrophilic or nucleophilic intermediates undergo C–N or C–C coupling to yield complex monomers like cyclohexanone oxime; and (iii) cascade electrocatalytic systems integrating biocatalysis, thermocatalysis, or photocatalysis to enable the synthesis of longer-chain polymer monomers. Emphasis is placed on universal catalyst design principles – including coordination environment regulation, electronic structure modulation, and interfacial microenvironment engineering – as well as mechanistic insights from in situ characterization and theoretical modeling. In addition, this review introduces techno-economic analysis (TEA) and life-cycle assessment (LCA) to evaluate the energy consumption and economic viability of electrocatalytic systems, and further discusses the critical impact of product separation and purification on overall energy efficiency and process feasibility. Finally, perspectives are provided on the future development of renewable monomer electrosynthesis for sustainable polymer production.

The Cu–Ni alloy interface synergistically couples intermediate adsorption and hydrogenation during nitrate reduction: Cu sites activate nitrogen oxide intermediates, while Ni sites generate active hydrogen to accelerate hydrogenation.

The carbon dioxide reduction reaction (CO₂RR) is a promising strategy for converting CO₂ into high-value chemicals. However, the rational design of efficient catalysts for steering product selectivity toward specific high-value chemicals continues to be a central goal in electrocatalysis research. Recently, nanoporous confined electrocatalysts have garnered attention due to their unique pore structures, which not only increase the accessibility and utilization of active sites but also promote the enrichment and stabilization of key reaction intermediates and modulate the local reaction microenvironment. These combined effects contribute to improved reaction kinetics and enhanced product selectivity. This review systematically summarizes the mechanistic foundations of nanoporous confinement in CO₂RR, emphasizing its role in governing reaction pathways and selectivity. We introduce the fundamental design principles of nanoporous confined electrocatalysts, detailing how their pore size, tortuosity, connectivity influence CO₂ diffusion, local concentration gradients, and electrolyte accessibility. Then highlight how confinement-induced spatial regulation facilitates intermediate accumulation, directional proton transfer, and local pH modulation, collectively steering product selectivity toward desired C₁ and multi-carbon (C₂₊) products. Representative material systems and structure-performance relationships are discussed to illustrate these effects. Finally, we summarize the current challenges in mechanistic understanding and practical implementation, and propose future directions for developing nanoporous systems that integrate controlled transport, catalytic reactivity, and system-level scalability.

Achieving industrial‐level electrochemical CO ₂ reduction to formate remains a significant challenge due to limitations in catalyst selectivity and interfacial proton management at high current densities. In a recent study, Prof. Guo and colleagues report the development of Turing‐structured electrocatalysts, which incorporate reaction‐diffusion‐inspired topologies to engineer mesoscale surface patterns. This design enables precise modulation of the interfacial microenvironment, enhancing CO ₂ activation and suppressing competing hydrogen evolution. The resulting catalysts achieve efficient and stable CO ₂ ‐to‐formate conversion under industrially relevant conditions, offering a promising strategy for scalable carbon‐neutral chemical production.

The renewable electricity-driven CO₂ and CO reduction represents a promising approach for reducing the CO₂ footprint toward carbon neutrality. Substantial research developments have been achieved in designing catalysts and reaction interfaces for enhanced electrocatalytic activity and selectivity, and the investigation and understanding of the complex reaction mechanisms have also been extensively investigated by both in situ characterizations and theoretical investigations. Although quasi-equilibrium and rate-determining step assumptions are widely used in electrochemical kinetics, the overall reaction rate is generally determined by a series of elementary steps, and the influence of a certain elementary step for the overall reaction rate can be quantified based on the degree of rate control theory. For the complicated reaction networks of CO₍₂₎ reduction, not only the rate-determining steps but also the subsequent selectivity-determining steps play critical roles, especially in the product selectivity. In this Perspective, we summarize the strategies that can tune the activity and selectivity of CO₍₂₎ reduction based on their impacts on the rate-determining steps and selectivity-determining steps, respectively. In addition, we also describe the coupling of CO₂ electroreduction with other (electro)chemical reactions, such as nitrite reduction and methane oxidation, to form value-added products. At the end, the current challenges and opportunities in this field are discussed to inspire further development in the next stage.

We engineered Cu/CeO_x and Cu/CuCeO_x solid solutions, enhancing *H and *CO binding in CO₂RR. Cu/CeO_x boosts *H coverage via faster water dissociation, while Cu/CuCeO_x augments *CO adsorption, selectively reducing CO₂ to CH₄ or C₂H₄.