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The Li−CO2 batteries utilizing greenhouse gas CO2 possess advantages of high energy density and environmental friendliness. However, these batteries following Li2CO3‐product route typically exhibit low work voltage (<2.5 V) and energy efficiency. Herein, we have demonstrated for the first time that cobalt phthalocyanine (CoPc) as homogeneous catalyst can elevate the work plateau towards 2.98 V, which is higher than its theoretical discharge voltage without changing the Li2CO3‐product route. This unprecedented discharge voltage is illustrated by mass spectrum and electrochemical analyses that CoPc has powerful adsorption capability with CO2 (−7.484 kJ mol−1) and forms discharge intermediate of C33H16CoN8O2. Besides high discharge capacity of 18724 mAh g−1 and robust cyclability over 1600 hours (1000 mAh g−1 cut‐off) at a current density of 100 mA g−1, the batteries show high temperature adaptability (−30–80 °C). Our work is paving a promising avenue for the progress of high‐efficiency Li−CO2 batteries. [ABSTRACT FROM AUTHOR]

Directly coupling N2 and CO2 to synthesize urea by photocatalysis paves a sustainable route for urea synthesis, but its performance is limited by the competition of photogenerated electrons between N2 and CO2, as well as the underutilized photogenerated holes. Herein, we report an efficient urea synthesis process involving photogenerated electrons and holes in respectively converting CO2 and N2 over a redox heterojunction consisting of WO3 and Ni single‐atom‐decorated CdS (Ni1‐CdS/WO3). For the photocatalytic urea synthesis from N2 and CO2 in pure water, Ni1‐CdS/WO3 attained a urea yield rate of 78 μM h−1 and an apparent quantum yield of 0.15 % at 385 nm, which ranked among the best photocatalytic urea synthesis performance reported. Mechanistic studies reveal that the N2 was converted into NO species by ⋅OH radicals generated from photogenerated holes over the WO3 component, meanwhile, the CO2 was transformed into *CO species over the Ni site by photogenerated electrons. The generated NO and *CO species were further coupled to form *OCNO intermediate, then gradually transformed into urea. This work emphasizes the importance of reasonably utilizing photogenerated holes in photocatalytic reduction reactions. [ABSTRACT FROM AUTHOR]

The high activation barrier, inferior rate performance, and short cycling life severely constrain the practical applications of the high‐capacity Li2S cathode. Herein, we fabricate a Li2S−Cu nanocomposite with a drastically reduced activation potential, fast rate capability, and extraordinary cycling stability even under a practically relevant areal capacity of 2.96 mAh cm−2. Detailed experimental investigations aided by theoretical calculations indicate that instead of converting to S8 via troublesome soluble lithium polysulfides, Li2S is thermodynamically and kinetically more favorable to react with Cu by the displacement reaction, which alters the redox couple from Li2S/S to Cu/Cu2S, leading to the excellent electrochemical performance. Moreover, the stability of the composite is demonstrated in the full‐cell configuration consisting of commercial graphite anodes. This work provides an innovative and effective approach to realize highly activated and stable Li2S cathode materials. [ABSTRACT FROM AUTHOR]

Photoinduced syntheses offer significant advantages over conventional thermal strategies, including improved control over reaction kinetics and low synthesis temperatures, affording nanoparticles with nontrivial and thermodynamically unstable structures. However, the photoinduced syntheses of non-metallic nanocrystalline products (such as metal sulfides) have not yet been reported. Herein, we demonstrate the first photoinduced synthesis of ultrafine (sub-2 nm) Ag2S quantum dots (QDs) from Ag nanoparticles at 10 °C. By thorough investigation of the mechanism for the transformation, a fundamental link was established between the intrinsic structures of the molecular intermediates and the final Ag2S products. Our results confirm the viability of low-temperature photochemical approaches in metal sulfide synthesis, and demonstrate a new rule which could be followed in it. [ABSTRACT FROM AUTHOR]

Directly coupling N2 and CO2 to synthesize urea by photocatalysis paves a sustainable route for urea synthesis, but its performance is limited by the competition of photogenerated electrons between N2 and CO2, as well as the underutilized photogenerated holes. Herein, we report an efficient urea synthesis process involving photogenerated electrons and holes in respectively converting CO2 and N2 over a redox heterojunction consisting of WO3 and Ni single‐atom‐decorated CdS (Ni1‐CdS/WO3). For the photocatalytic urea synthesis from N2 and CO2 in pure water, Ni1‐CdS/WO3 attained a urea yield rate of 78 μM h−1 and an apparent quantum yield of 0.15 % at 385 nm, which ranked among the best photocatalytic urea synthesis performance reported. Mechanistic studies reveal that the N2 was converted into NO species by ⋅OH radicals generated from photogenerated holes over the WO3 component, meanwhile, the CO2 was transformed into *CO species over the Ni site by photogenerated electrons. The generated NO and *CO species were further coupled to form *OCNO intermediate, then gradually transformed into urea. This work emphasizes the importance of reasonably utilizing photogenerated holes in photocatalytic reduction reactions. [ABSTRACT FROM AUTHOR]