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Research on visible-light photocatalysts of metal nanoparticles (NPs) has focused on increasing the reactant conversion by light-excited charges (electrons and positively charged holes). However, light irradiation can accelerate catalysis by other mechanisms. Here, we report that 650 nm wavelength irradiation of 0.75 W·cm-2 significantly increases nitrile yield of ammoxidation of primary aromatic alcohols with an ammonium salt over supported Pd NPs at 80 °C in air. We found that the desorption of the nitrile product from the catalyst is the rate-determining step; the irradiation promotes not only alcohol oxidation and subsequent aldehyde cyanation over the Pd NPs but also the nitrile desorption selectively via resonance energy transfer to achieve a high nitrile yield. This new mechanism provides a knob for the exquisite control of catalytic reaction pathways for ecofriendly synthesis.

Surface-plasmon-mediated phenylacetylide intermediate transfer from the Cu to the Pd surface affords a novel mechanism for transmetalation, enabling wavelength-tunable cross-coupling and homo-coupling reaction pathway control. C−C bond forming Sonogashira coupling and Glaser coupling reactions in O2 atmosphere are efficiently driven by visible light over heterogeneous Cu and Pd nanoparticles as a mixed catalyst without base or other additives. The reaction pathway can be controlled by switching the excitation wavelength. Shorter wavelengths (400–500 nm) give the Glaser homo-coupling diyne, whereas longer wavelength irradiation (500–940 nm) significantly increases the degree of cross-coupling Sonogashira coupling products. The ratio of the activated intermediates of alkyne to the iodobenzene is wavelength dependent and this regulates transmetalation. This wavelength-tunable reaction pathway is a novel way to optimize the product selectivity in important organic syntheses.

Chalcones enable the biosynthesis of flavonoids which protect plants from infections and parasites and have emerged as valuable medicines against diverse human diseases. The common way to synthesize chalcones through the homogeneous catalytic Claisen-Schmidt condensation reaction is compromised from difficult catalyst recovery, waste generation, side reactions, and low yield. As a solution, solid base catalysts are developed as a green catalytic process. It is still a major challenge to synthesize highly active heterogeneous catalysts with a quick, simple, sustainable, and economical approach in the chalcone synthesis. To address these issues, a simple and sustainable synthesis of chalcones has been accomplished here by the solvent-free Claisen-Schmidt condensation reaction using magnesium oxide (MgO) nanosheets as the catalyst. The heterogeneous two-dimensional (2D) MgO catalyst was synthesized using salt recovered from inexhaustible seawater, using an atmospheric pressure plasma (APP)-assisted method making the whole method sustainable and potentially economically feasible. The catalytic activity of the 2D nanosheets was compared with irregular MgO nanoparticles. Irregular MgO showed 25% of benzaldehyde and 10% of acetophenone conversion, while 2D MgO showed >99% of conversion of both reactants with a product selectivity of 100%, while no products were formed in the absence of a catalyst. The effect of substituent groups on the benzaldehyde moiety on the catalytic activity was also analysed. The prepared 2D MgO catalyst showed reusability up to three cycles without any significant loss in the catalytic activity.

Direct photoexcitation of metal nanoparticles (NPs) can induce selective chemical reactions that are difficult to achieve with thermal energy. Here, we report that visible-light photoexcitation on palladium (Pd) NPs shows distinct particle size dependence; small Pd NPs (sub-3.0-nanometer) with low Pd loading (0.5 wt%) as a catalyst achieved excellent yield (100%) for Heck reaction. This is because (1) the light absorption of small Pd particles is more intensive than that of large Pd particles even if the Pd loadings are similar, and (2) the chemisorption of the reactants on the small Pd particles is stronger. The chemical adsorption can result in the hybridization of adsorbate orbitals and metal electronic states, and the photon absorption may directly excite the hybridized electronic states driving the reactions. This highly efficient visible-light-driven Pd nanocatalyst with low precious metal loading represents a promising step towards efficient cost-effective photocatalysis that operates under real-world conditions.

We report a bioinspired emulsion microreactor composed of an electrical double layer to mimic the functions of cell membranes. This "artificial cell"can modulate the phase-oriented transport of reagents at the oil-liquid interface via the electrical double layer, affording a powerful tool to optimize the selectivity in a catalytic reaction. This journal is

The inclusion of long chain alkyl-amine organics in perovskite solar cells (PSCs) has been reported to enhance water-resistance of perovskite films, but this strategy lowers device efficiency at the same time. Herein, we develop an approach that combines molecular dimensionality control and interfacial passivation of perovskite layers using a novel post-device treatment (PDT) with the vapour of ethylene-amine salts of different carbon chain lengths to improve both efficiency and stability of the PSCs. The effect of a series of ligand vapours including ethylenediamine (EDA), diethylenetriamine (DETA) and triethylenetetramine (TETA) was systematically investigated. A thin hydrophobic two-dimensional (2D) perovskite capping layer formed in the device after the 3D perovskite was exposed to the vapour of long chain ethylene-amine molecules, such as DETA and TETA, which protected the underlying bulk 3D perovskite layer from moisture attack. An improved energy level alignment was obtained in the treated devices and that a reduced density of defects was present in the perovskite after treatment with DETA and TETA vapours. Consequently, enhanced efficiency from 17.07% to 18.09% (DETA) and improved moisture stability with PCE retention from 73.8% to 90.0% (TETA) under a relative humidity>65% for 1000 h were achieved by this vapour treatment respectively.

Advanced electrochemical energy storage devices are in high demand to meet the need for both short-term high power pulse and long-term durable energy outputs. To achieve this goal, a majority of studies have focused on optimization of solid electrode materials. However, the issue of slow diffusion of ions in electrode materials causes unsatisfactory power density in the energy storage devices. In this work, soluble dual-redox additives in an aqueous electrolyte were employed to combine with a S/P co-doped carbon based cathode and a carbon cloth (CC) based anode to construct an aqueous zinc bromine (Zn-Br2) "supercapattery". The as-fabricated supercapattery possessed electrical-double-layer type, pseudocapacitive, and battery-type charge storage in both cathode and anode and successfully united capacitive character and battery-like character in one device. The benefits of the triple functions of charge storage resulted in an extremely high energy density of 270 W h kg-1 and a maximum power density of 9300 W kg-1. The capacitive and pseudocapacitive charge storage processes in the Zn-Br2 supercapattery are able to provide peak power output. Meanwhile, the diffusion-controlled battery-type redox reactions can meet the requirement for high energy. This work provides a new pathway towards development of electrochemical energy storage devices with both battery-level energy density and capacitor-level power density.