Electrocatalytic carbon dioxide reduction reaction (CO2RR) holds significant potential to promote carbon neutrality. However, the selectivity toward multicarbon products in CO2RR is still too low to meet practical applications. Here the authors report the delicate synthesis of three kinds of Ag–Cu Janus nanostructures with {100} facets (JNS‐100) for highly selective tandem electrocatalytic reduction of CO2 to multicarbon products. By controlling the surfactant and reduction kinetics of Cu precursor, the confined growth of Cu with {100} facets on one of the six equal faces of Ag nanocubes is realized. Compared with Cu nanocubes, Ag65–Cu35 JNS‐100 demonstrates much superior selectivity for both ethylene and multicarbon products in CO2RR at less negative potentials. Density functional theory calculations reveal that the compensating electronic structure and carbon monoxide spillover in Ag65–Cu35 JNS‐100 contribute to the enhanced CO2RR performance. This study provides an effective strategy to design advanced tandem catalysts toward the extensive application of CO2RR.

Developing metal-free electrocatalysts for direct nitrate-to-ammonia reduction is promising to remediate wastewater yet challenged by the poor ammonia selectivity. Amorphization has become an emerging strategy to afford conventional materials with exotic physical, chemical, and electronic properties. Transient laser heating of polymers produces graphene with an unusual polycrystalline lattice, yet the control of graphene amorphicity is difficult due to the extreme conditions and fast kinetics of the lasing process. Here, we report the synthesis of amorphous graphene with a tailorable heterophase, topologically disparate from crystalline graphene and amorphous carbon. Atomic-resolution imaging reveals the intermediate crystallinity comprising both six-membered rings and polygons, the ratio of which directly correlates with the aromatic structures of the precursors. These amorphous graphenes, as metal-free catalysts, show high performance in direct nitrate-to-ammonia electroreduction. The performance is associated with the amorphicity of graphene and reaches a maximum ammonia Faradaic efficiency of 83.7% at −0.94 V vs reversible hydrogen electrode. X-ray pair distribution functions and paramagnetism disclose the elongated carbon–carbon bonds and rich unpaired electrons in amorphous graphene, which exhibit more favorable adsorption of nitrate as suggested by theoretical calculations. Our findings shed light on the controllable synthesis of graphene with unusual topologies that could find broad applications in electronics, catalysis, and sensors.

Electrochemical CO2 reduction reaction (CO2RR) to produce value‐added products has received tremendous research attention in recent years. With research efforts across the globe, remarkable advancement has been achieved, including the improvement of selectivity for the reduction products, the realization of efficient reduction beyond two electrons, and the delivery of industrially relevant current densities. In this review, we introduce the recent development of nanomaterials for CO2RR, including the zero‐dimensional graphene quantum dots, two‐dimensional materials such as metal chalcogenides and metal/covalent organic framework, single‐atom catalysts, and nanostructured metal catalysts. The engineering of materials into three‐dimensional structure will also be discussed. Finally, we will provide a summary of the catalytic performance and perspectives on future development.

Recent advances in laser-induced graphene (LIG) for environmental applications are comprehensively reviewed. Challenges and opportunities in solving environmental issues using LIG are discussed.

The incorporation of charged functional groups is effective to modulate the activity of molecular complexes for the CO2 reduction reaction (CO2RR), yet long‐term heterogeneous electrolysis is often hampered by catalyst leaching. Herein, an electrocatalyst of atomically thin, cobalt‐porphyrin‐based, ionic–covalent organic nanosheets (CoTAP‐iCONs) is synthesized via a post‐synthetic modification strategy for high‐performance CO2‐to‐CO conversion. The cationic quaternary ammonium groups not only enable the formation of monolayer nanosheets due to steric hindrance and electrostatic repulsion, but also facilitate the formation of a *COOH intermediate, as suggested by theoretical calculations. Consequently, CoTAP‐iCONs exhibit higher CO2RR activity than other cobalt‐porphyrin‐based structures: an 870% and 480% improvement of CO current densities compared to the monomer and neutral nanosheets, respectively. Additionally, the iCONs structure can accommodate the cationic moieties. In a flow cell, CoTAP‐iCONs attain a very small onset overpotential of 40 mV and a stable total current density of 212 mA cm–2 with CO Faradaic efficiency of >95% at −0.6 V for 11 h. Further coupling the flow electrolyzer with commercial solar cells yields a solar‐to‐CO conversion efficiency of 13.89%. This work indicates that atom‐thin, ionic nanosheets represent a promising structure for achieving both tailored activity and high stability.