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An electric field in a photocatalytic system consisting of Au@TiO2 yolk-shell hollow spheres is created to enhance the generation of electron-hole pairs and remit the charge-carrier recombination. Local surface plasmon resonance (LSPR)-mediated local electromagnetic field nearby Au nanoparticles cannot only enhance the local generation and subsequent separation of electron-hole pairs in TiO2 shells to improve the photoreduction yield of CO2, but also facilitate chemical reactions involving multiple e(-)/H(+) transfer processes to allow the formation of high-grade carbon species (C2H6), which was rarely observed in precedent CO2 photocatalytic reduction systems. The work may provide a new viewpoint for designing photocatalysts for artificial photosynthesis involving multiple reactions.

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An all-solid-state Z-scheme system array consisting of an Fe2V4O13 nanoribbon (NR)/reduced graphene oxide (RGO)/CdS nanoparticle grown on the stainless-steel mesh was rationally designed for photoconversion of gaseous CO2 into renewable hydrocarbon fuels (methane: CH4).

A series of bimetallic Ni–Fe phosphide nanocomposites with a controlled architecture and composition are finely engineered for efficient electrocatalytic water oxidation.

Controllable designing of heteroatom-doped carbon catalysts provides an insightful strategy for boosting the performance and kinetics of the oxygen reduction/evolution reaction (ORR/OER). However, the role of oxygen species is usually omitted. Herein, a facile oxygen engineering strategy is proposed to tune the oxygen species in N-doped porous carbon nanofibers (NPCNFs-O) via a facile electrospinning method, in which βcyclodextrin acts as the pore inducer and oxygen regulator. Benefitting from the large specific surface area and synergistic effect of N,O codoping, the NPCNF-O catalyst exhibits superior ORR (E 1/2 = 0.85 V vs reversible hydrogen electrode (RHE)) and OER (E j = 10 = 1.556 V vs RHE) activities with excellent stability. Both experimental and theoretical calculations verify the crucial role of carboxyl groups, which regulate the local charge density and reduce the reaction energy barrier for enhancing the oxygen electrocatalytic activity. Moreover, a rechargeable zinc−air battery using NPCNF-O as the air cathode demonstrates a maximum power density of 125.1 mW cm −2 and long-term durability. Importantly, NPCNF-O can be served as an integrated freestanding electrode for portable zinc−air batteries. The work brings brilliant fundamental insights for constructing efficient metal-free carbon material catalysts for future energy conversion and storage systems.

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Molecular layer deposition (MLD) is a processing technology for depositing ultrathin polymer or inorganic-organic hybrid films. It is a subset of atomic layer deposition (ALD) and has attracted tremendous attention because of its self-limiting nature, excellent conformality, chemical selectivity and low reaction temperature. [1][2][3][4][5][6] However, because of factors like low vapor pressure and thermal sensitivity of many organic molecules and poor understanding of vapor-phase organic coupling reactions, [7] the variety of combinations of organic and inorganic reactants that have been used for successful MLD is sparse. Up to now, only a few organic-inorganic polymer films, including alucone, [8][9][10][11] zincone, [12] and titanicone, [13,14] have been grown through MLD and those were mainly based on reactions between metal alkyl/chloride and glycol/glycerol. Given the great promise of MLD, it is highly demanded to develop new processing strategies for MLD.One important aspect for producing a larger range of organic-inorganic mixtures is the variability of compositions of the constituting organic and inorganic fractions of the resulting films. A limitation to rather short organic spacers, such as glycol, between the metal ions is a bottleneck for the synthesis of films with a broader range of organic-inorganic volume ratios. By designing new processing strategies for the organic component, the properties of the resulting films can be more easily tuned by varying their composition. These organic-inorganic hybrid films can be further used to produce porous metal oxide films by removing the organic component and the porosity of the resulting inorganic films will depend on the volume occupied by the organic constituting part, making such films attractive for many applications such as catalysis, separation, sensing, and energy conversion and storage.As an important semiconductor, TiO 2 has been intensely investigated using various ALD processes for its evident application potential in solar-energy devices, environmental remediation, and as catalyst support. [15][16][17][18][19][20] However, due to the ALD growth characteristics these TiO 2 films are intrinsically pinhole-free with low specific surface areas, resulting in low photocatalytic activity. [19,20] Recently, the research groups of George, Yerushalmi, and our group reported nearly in parallel the successful preparation of porous TiO 2 by annealing or UV exposure of Ti-containing hybrid organic-inorganic films (titanicones) produced by MLD using TiCl 4 and glycol or glycerol as reactants. [13,14,21] However, their activity is only efficient with ultraviolet light irradiation because of the wide band gap of TiO 2 (3.2 eV for anatase). Therefore, developing new MLD processes to grow porous TiO 2 films with visible light response and larger surface area is very welcome for such applications.Herein, we demonstrate a novel MLD process for preparing porous N-doped TiO 2 films. The process is based on a new strategy, a four-step ABCB reaction sequence using titan...