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The comprehension of activity and selectivity origins of the electrooxidation of organics is a crucial knot for the development of a highly efficient energy conversion system that can produce value-added chemicals on both the anode and cathode. Here, we find that the potential-retaining trivalent nickel in NiOOH (Fermi level, -7.4 eV) is capable of selectively oxidizing various primary alcohols to carboxylic acids through a nucleophilic attack and nonredox electron transfer process. This nonredox trivalent nickel is highly efficient in oxidizing primary alcohols (methanol, ethanol, propanol, butanol, and benzyl alcohol) that are equipped with the appropriate highest occupied molecular orbital (HOMO) levels (-7.1 to -6.5 eV vs vacuum level) and the negative dual local softness values (Δ s k , -0.50 to -0.19) of nucleophilic atoms in nucleophilic hydroxyl functional groups. However, the carboxylic acid products exhibit a deeper HOMO level (<-7.4 eV) or a positive Δ s k , suggesting that they are highly stable and weakly nucleophilic on NiOOH. The combination (HOMO, Δ s k ) is useful in explaining the activity and selectivity origins of electrochemically oxidizing alcohols to carboxylic acid. Our findings are valuable in creating efficient energy conversions to generate value-added chemicals on dual electrodes.

Photocatalytic CO 2 conversion into carbonaceous fuels through artificial photosynthesis is beneficial to global warming mitigation and renewable resource generation. However, a high cost is always required by special CO 2 -capturing devices for efficient artificial photosynthesis. For achieving highly efficient photocatalytic CO 2 reduction (PCR) directly from natural air, we report rose-like BiOCl that is rich in Bi vacancies (V Bi ) assembled by nanosheets with almost fully exposed active {001} facets. These rose-like BiOCl with V Bi assemblies provide considerable adsorption and catalytic sites, which hoists the CO 2 capture and reduction capabilities, and thus expedites the PCR to a superior value of 21.99 μmol·g -1 ·h -1 CO generation under a 300 W Xe lamp within 5 h from natural air. The novel design and construction of a photocatalyst in this work could break through the conventional PCR system requiring compression and purification for CO 2 , dramatically reduce expenses, and open up new possibilities for the practical application of artificial photosynthesis.

The promotion of magnetic field on catalytic performance has attracted extensive attention for a long time, and substantial improvements have been achieved in some catalysis fields. However, because the Zeeman energy is several orders of magnitude weaker, magnetic field seems unable to alter the band structure and has a negligible effect on semiconductor photocatalytic performance, which makes this task a great challenge. On the other hand, the spin-related behavior usually plays an important role in determining catalytic performance. For example, in some molecular catalysis, such as photosystem II, ferromagnetic alignment of the active material results in spin-oriented electrons, which are selected and accumulated at the interface, leading to great promotion of the oxygen evolution reaction activity. Here, we propose a magnetoresistance-related strategy to boost the carrier transfer efficiency and apply it in α-Fe 2 O 3 /reduced graphene oxide hybrid nanostructures (α-Fe 2 O 3 /rGO) to improve the photocatalytic performance under magnetic field. We show that both the degradation rate constant and photocurrent density of α-Fe 2 O 3 /rGO can be dramatically enhanced with the application of magnetic field, indicating the promotion of the photocatalytic performance.