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Electrochemical CO₂reduction offers a compelling route to mitigate atmospheric CO₂concentration and store intermittent renewable energy in chemical bonds. Beyond C₁, C₂₊feedstocks are more desirable due to their higher energy density and more significant market need. However, the CO₂‐to‐C₂₊reduction suffers from significant barriers of CC coupling and complex reaction pathways. Due to remarkable tunability over morphology/pore architecture along with great feasibility of functionalization to modify the electronic and geometric structures, carbon materials, serving as active components, supports, and promoters, provide exciting opportunities to tune both the adsorption properties of intermediates and the local reaction environment for the CO₂reduction, offering effective solutions to enable CC coupling and steer C₂₊evolution. However, general design principles remain ambiguous, causing an impediment to rational catalyst refinement and application thrusts. This review clarifies insightful design principles for advancing carbon materials. First, the current performance status and challenges are discussed and effective strategies are outlined to promote C₂₊evolution. Further, the correlation between the composition, structure, and morphology of carbon catalysts and their catalytic behavior is elucidated to establish catalytic mechanisms and critical factors determining C₂₊performance. Finally, future research directions and strategies are envisioned to inspire revolutionary advancements.

Herein, we report that a new flexible coordination network,NiL₂(L=4‐(4‐pyridyl)‐biphenyl‐4‐carboxylic acid), with diamondoid topology switches between non‐porous (closed) and several porous (open) phases at specific CO₂and CH₄pressures. These phases are manifested by multi‐step low‐pressure isotherms for CO₂or a single‐step high‐pressure isotherm for CH₄. The potential methane working capacity ofNiL₂approaches that of compressed natural gas but at much lower pressures. The guest‐induced phase transitions ofNiL₂were studied by single‐crystal XRD, in situ variable pressure powder XRD, synchrotron powder XRD, pressure‐gradient differential scanning calorimetry (P‐DSC), and molecular modeling. The detailed structural information provides insight into the extreme flexibility ofNiL₂. Specifically, the extended linker ligand,L, undergoes ligand contortion and interactions between interpenetrated networks or sorbate–sorbent interactions enable the observed switching.

Herein, we report that a new flexible coordination network,NiL₂(L=4‐(4‐pyridyl)‐biphenyl‐4‐carboxylic acid), with diamondoid topology switches between non‐porous (closed) and several porous (open) phases at specific CO₂and CH₄pressures. These phases are manifested by multi‐step low‐pressure isotherms for CO₂or a single‐step high‐pressure isotherm for CH₄. The potential methane working capacity ofNiL₂approaches that of compressed natural gas but at much lower pressures. The guest‐induced phase transitions ofNiL₂were studied by single‐crystal XRD, in situ variable pressure powder XRD, synchrotron powder XRD, pressure‐gradient differential scanning calorimetry (P‐DSC), and molecular modeling. The detailed structural information provides insight into the extreme flexibility ofNiL₂. Specifically, the extended linker ligand,L, undergoes ligand contortion and interactions between interpenetrated networks or sorbate–sorbent interactions enable the observed switching.

Porous materials capable of selectively capturing CO₂from flue‐gases or natural gas are of interest in terms of rising atmospheric CO₂levels and methane purification. Size‐exclusive sieving of CO₂over CH₄and N₂has rarely been achieved. Herein we show that a crystal engineering approach to tuning of pore‐size in a coordination network, [Cu(quinoline‐5‐carboxyate)₂]_n(Qc‐5‐Cu) ena+bles ultra‐high selectivity for CO₂over N₂(S_CN≈40 000) and CH₄(S_CM≈3300).Qc‐5‐Cu‐sql‐β, a narrow pore polymorph of the square lattice (sql) coordination networkQc‐5‐Cu‐sql‐α,adsorbs CO₂while excluding both CH₄and N₂. Experimental measurements and molecular modeling validate and explain the performance.Qc‐5‐Cu‐sql‐βis stable to moisture and its separation performance is unaffected by humidity.