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Ni-based coordination compounds, during the oxygen evolution reaction (OER), self-reconstruct to produce NiOOH, which are the real active sites. Thus, encouraging the self-reconstruction of pre-catalysts to generate more NiOOH species has emerged as an effective strategy for enhancing the activity. In this research, we utilized three coordination compounds, Ni(N(CN)2)2, Ni(NCN), and Ni(HNCN)2, to examine the effect of three distinct ligands (–N(CN)2–, –HNCN–, and –NCN–) on the local electronic structure of coordinated Ni, aiming to promote the degree of self-reconstruction during the OER. XPS studies and in situ Raman spectroscopy revealed a significant relationship between the electron-donating properties of coordinated Ni and the self-reconstruction abilities of the pre-catalysts. Notably, Ni coordinated with –N(CN)2– exhibits a high tendency to donate electrons, leading to facile reconstruction of Ni(N(CN)2)2 into Ni(OOH)–(N(CN)2). As a result, Ni(OOH)–(N(CN)2) displays high OER activity (264 mV @ 10 mA cm−2 and Tafel slope of 40.80 mV dec−1) in comparison to Ni(OOH)–(NCN) (290 mV @ 10 mA cm−2 and Tafel slope of 55.63 mV dec−1) and Ni(OOH)–(HNCN) (307 mV @ 10 mA cm−2 and Tafel slope of 77.70 mV dec−1). These findings offer new perspectives on designing and developing innovative catalysts to enhance OER efficiency. [ABSTRACT FROM AUTHOR]

Solar‐driven conversion of renewable biomass resources into high‐density hydrocarbon fuels can effectively realize biomass valorization and renewable energy conversion. In this work, an efficient self‐sensitized [2 + 2] photocycloaddition process is explored to develop highly strained fuel with high yield using norbornene and biomass‐derived cyclohexenone as feedstocks. The enhancement mechanism is revealed by phosphorescent measurement and theoretical calculation, and a reasonable reaction path for self‐sensitized [2 + 2] co‐cycloaddition is proposed. When using methanol as solvent, the apparent activation energy of co‐cycloaddition is 21.37 W/mol, which is lower than that of self‐cycloaddition (31.57 W/mol). Importantly, the jet‐fuel‐range highly strained fuel has high density (0.986 g/cm3) and high volumetric net heat of combustion (41.14 MJ/L), which are 5.34% and 4.39% higher than those of JP‐10, respectively. This work proposes a green and effective pathway for the preparation of high‐performance hydrocarbon fuel with polycyclic‐asymmetric structure. [ABSTRACT FROM AUTHOR]

The replacement of the oxygen evolution reaction with a higher valuable oxidation process can overcome the sluggish kinetics to promote renewable hydrogen production, simultaneously achieving energy storage and environmental protection. However, the effective integration of two redox half-reactions in one photocatalytic reaction system is still a challenge. Here the p-diethynylbenzene and dibenzothiophene sulfone copolymer (PEB-DBT) is well-designed to couple with α-Fe2O3via a palladium-catalyzed Sonogashira cross-linking reaction, forming a heterojunction with strong interfacial interaction. In particular, there is a different preferred charge transfer path of PEB-DBT/α-Fe2O3via modulating the work function difference in various solutions. The results suggest that the Z-scheme electron transfer pathway is predominant in triethanolamine (TEOA) and ofloxacin (OFL) solutions, instead of the type-II heterojunction that forms in H2O or methylene blue (MB). The Z-scheme PEB-DBT/α-Fe2O3 heterojunction has excellent performance in the hydrogen evolution half-reaction and OFL degradation, which is about 2.7 times and 3.3 times higher than that of pure PEB-DBT, respectively. Finally, it successfully achieved simultaneous photocatalytic H2 evolution and OFL degradation under visible light. [ABSTRACT FROM AUTHOR]