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The sluggishness of the complementary oxygen evolution reaction (OER) is reckoned as one of the major drawbacks in developing an energy‐efficient green hydrogen‐producing electrolyzer. An array of organic molecule oxidation reactions, operational at a relatively low potential, have been explored as a substitute for the OER. Glycerol oxidation reaction (GOR) has emerged as a leading alternative in this context because glycerol, a waste of biodiesel manufacturing, has become ubiquitous and accessible due to the significant growth in the biodiesel sector in recent decades. Additionally, the GOR generates several value‐added organic compounds following oxidation that enhance the cost viability of the overall electrolysis reaction. In this study, a low‐cost, room temperature operable, and energy‐efficient synthetic methodology has been developed to generate unique two‐dimensional CuO nanosheets (CuO NS). This CuO NS material was embedded on a carbon paper electrode, which showcased excellent glycerol electro‐oxidation performance operational at a moderately low applied potential. Formic acid is the major product of this CuO NS‐driven GOR (Faradaic efficiency ~80 %), as it is formed primarily via the glyceraldehyde oxidation pathway. This CuO NS material was also active for oxidizing other abundant alcohols like ethylene glycol and diethylene glycol, albeit at a relatively poor efficiency. Therefore, this robust CuO NS material has displayed the potential to be used in large‐scale electrolyzers functioning with HER/GOR reactions. [ABSTRACT FROM AUTHOR]

Developing a water‐soluble, oxygen‐tolerant, and acid‐stable synthetic H2 production catalyst is vital for renewable energy infrastructure. To access such an effective catalyst, we strategically incorporated enzyme‐inspired, multicomponent outer coordination sphere elements around the cobaloxime (Cl−Co−X) core with suitable axial coordination (X). Our cobaloximes with axial imidazole or L‐histidine coordination in photocatalytic HAT including the construction of anilines via a non‐canonical cross‐coupling approach is found superior compared to commonly used cobaloxime catalysts. The reversible Co(II)/Co(I) process is influenced by the axial N ligand's nature. Imidazole/L‐histidine with a higher pKa promptly produces H2 upon irradiation, leading to the improved reactivity compared to previously employed axial (di)chloride or pyridine analogue. [ABSTRACT FROM AUTHOR]

The strategic inclusion of nucleic bases adenine, cytosine, and thymine, in the form of outer coordination sphere, positively impacts the electro- and photocatalytic H2 production by cobaloxime cores. These cobaloxime derivatives showcased their optimal H2 production in acidic media due to specific protonation of adenine and cytosine below pH 5.0. [ABSTRACT FROM AUTHOR]

The strategic incorporation of the neurotransmitter dopamine around a cobaloxime core resulted in excellent electrocatalytic (rate 8400 s−1) and photocatalytic H2 production under neutral aqueous conditions. The influence of the synthetic outer coordination sphere features continues even with a phenylene–diimino–dioxime motif-coordinated cobalt core. [ABSTRACT FROM AUTHOR]

Electrochemical CO 2 reduction reaction (CO 2 RR), which is driven by electricity generated from renewable energy sources, is a promising technology for sustainably producing carbon-based chemicals or fuels. Several CO 2 RR catalysts have been explored to date, among which copper-based electrocatalysts are the most widely known for electrochemical CO 2 RR and are extensively studied for their ability to generate an array of products. Their low selectivity, however, hinders their possibility of being used for practical purposes. In this work, a microwave-assisted one-pot synthesized Cu x O/N-doped carbon demonstrates the electrochemical conversion of carbon dioxide into multiple C 1 products (mainly formate and methanol), with a maximum Faradaic efficiency of 95% in 0.10 m KHCO 3 aqueous solution at a moderately low applied potential of -0.55 V versus RHE (reversible hydrogen electrode). The in-depth theoretical study reveals the key contribution of pyridinic N-based N-doped carbon sites and Cu 2 O clusters in CO 2 adsorption and its subsequent conversion to formate and methanol via an energetically favorable formate pathway. The electrocatalyst continued to demonstrate CO 2 reduction to valuable C 1 products when a simulated flue gas stream containing 15% CO 2 along with 500 ppm SO x and 200 ppm NO x is used as an inlet feed., (© 2024 Wiley‐VCH GmbH.)

Developing a water-soluble, oxygen-tolerant, and acid-stable synthetic H 2 production catalyst is vital for renewable energy infrastructure. To access such an effective catalyst, we strategically incorporated enzyme-inspired, multicomponent outer coordination sphere elements around the cobaloxime (Cl-Co-X) core with suitable axial coordination (X). Our cobaloximes with axial imidazole or L-histidine coordination in photocatalytic HAT including the construction of anilines via a non-canonical cross-coupling approach is found superior compared to commonly used cobaloxime catalysts. The reversible Co(II)/Co(I) process is influenced by the axial N ligand's nature. Imidazole/L-histidine with a higher pKa promptly produces H 2 upon irradiation, leading to the improved reactivity compared to previously employed axial (di)chloride or pyridine analogue., (© 2024 Wiley-VCH GmbH.)

The strategic incorporation of the neurotransmitter dopamine around a cobaloxime core resulted in excellent electrocatalytic (rate 8400 s -1 ) and photocatalytic H 2 production under neutral aqueous conditions. The influence of the synthetic outer coordination sphere features continues even with a phenylene-diimino-dioxime motif-coordinated cobalt core.