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The acidic electrocatalytic conversion of CO2 to multi‐carbon (C2+) oxygenates is of great importance in view of enhancing carbon utilization efficiency and generating products with high energy densities, but suffering from low selectivity and activity. Herein, we synthesized Ag−Cu alloy catalyst with highly rough surface, by which the selectivity to C2+ oxygenates can be greatly improved. In a strongly acidic condition (pH=0.75), the maximum C2+ products Faradaic efficiency (FE) and C2+ oxygenates FE reach 80.4 % and 56.5 % at −1.9 V versus reversible hydrogen electrode, respectively, with a ratio of FEC2+ oxygenates to FEethylene up to 2.36. At this condition, the C2+ oxygenates partial current density is as high as 480 mA cm−2. The in situ spectra, control experiments and theoretical calculations indicate that the high generation of C2+ oxygenates over the catalyst originates from its large surface roughness and Ag alloying. [ABSTRACT FROM AUTHOR]

The photocatalytic conversion of benzylamine into imine is promising for industrial production and environmental protection. To develop photocatalysts with desirable compositions and microstructures is key to achieve high activity and selectivity. Here we propose the immobilization of Bi2O2CO3 on g‐C3N4 for the photocatalytic conversion of benzylamine. The Bi2O2CO3/g‐C3N4 catalyst possesses improved light absorption capacity, electron transmission rate and reduced electron‐hole recombination than pure Bi2O2CO3. It can efficiently catalyze benzylamine coupling reaction under mild conditions, i. e. at room temperature, with air as oxidant and no additional oxidant involved. The maximum turnover frequency value of N‐benzylbenzaldimine reaches 1555.3 μmol g−1 h−1 under this condition. The Bi2O2CO3/g‐C3N4 catalyst has potential in other photocatalytic reactions. [ABSTRACT FROM AUTHOR]

The photocatalytic oxidation of biomass‐derived benzyl alcohol provides a promising way for the synthesis of benzoic acid, which is an important intermediate with wide applications. To improve the efficiency of photocatalytic benzyl alcohol oxidation to benzoic acid is of great interest. In this work, we propose the utilization of NH2‐UiO‐66‐ID‐Fe catalyst for photocatalytic oxidation of benzyl alcohol to benzoic acid, where NH2‐UiO‐66 is a typically used metal‐organic framework, ID is indole‐2,3‐dione (ID) that has biocompatibility, light absorption property and can be covalently combined with amino‐functionalized substances. The NH2‐UiO‐66‐ID‐Fe catalyst exhibits improved light absorption and photo‐generated electron‐hole separation ability compared with NH2‐UiO‐66. The photocatalytic performance of NH2‐UiO‐66‐ID‐Fe was examined for the oxidation of bio‐based benzyl alcohol under mild conditions of air atmosphere, room temperature and no additive or additional oxidant involved. The results show that the conversion of benzyl alcohol and the selectivity to benzoic acid could both reach over 99 % in 6 h, and the generation rate of benzoic acid per gram of catalyst is 3.36 mmol g−1 h−1. The reaction mechanism was detected by radical trapping method and in situ electron paramagnetic resonance. This study presents an efficient and environmentally benign avenue for the synthesis of carboxylic acid compounds. [ABSTRACT FROM AUTHOR]

Photocatalytic conversion of solar energy to hydrogen (H2) provides an efficient way for energy supply and storage. It is of great importance to improve the H2 production efficiency by constructing photocatalysts with rapid charge transfer and separation and a low energy barrier for H2 production. Here, we demonstrate high-efficiency photocatalytic H2 production on Cu-coordinated mesoporous g-C3N4 nanotubes. The catalyst exhibits a photocatalytic H2 production rate of 6.53 mmol g−1 h−1 under visible-light irradiation (λ > 420 nm), which is much higher than that over bulk g-C3N4 (0.58 mmol g−1 h−1) under the same conditions. Advanced characterization and density functional theory calculations reveal that such a catalyst has stronger light absorption, facilitated carrier transfer and separation, and a reduced H2 evolution barrier than Cu-free g-C3N4 nanotubes. This study provides a new insight into the design of photocatalytically active sites of catalysts for high-performance H2 production. [ABSTRACT FROM AUTHOR]

To develop high-performance metal-organic frameworks (MOFs) for catalysis is of great importance. Here, we synthesized the mesoporous Cu3−xZnx(BTC)2 (BTC = benzene-1,3,5-tricarboxylate) nanocubes in a deep eutectic solvent of ZnCl2/ethylene glycol solution. The route can proceed at room temperature and the reaction time needed is shortened to be 30 min, which is superior to the conventional solvothermal route that usually needs high temperature and long reaction time. The formation mechanism of the mesoporous Cu3−xZnx(BTC)2 nanocubes in deep eutectic solvent (DES) was investigated by in situ synchrotron X-ray diffraction/small angle X-ray scattering/X-ray absorption fine structure conjunction technique. The mesoporous Cu3−xZnx(BTC)2 nanocubes exhibit high catalytic activity and reusability for cyanosilylation reaction of benzaldehyde and aerobic oxidation reaction of benzylic alcohol. [ABSTRACT FROM AUTHOR]

We demonstrate the electrochemical conversion of carbon dioxide into multi-carbon products catalyzed by Cu/Cu2O nanocrystals, with a maximum C2+ faradaic efficiency of 75% in 0.10 M K2SO4 aqueous solution at −2.0 V versus Ag/AgCl and a partial current density of 34 mA cm−2. [ABSTRACT FROM AUTHOR]

Here, SnS2/polypyrrole (PPy) was synthesized, which shows high catalytic activity for the photocatalytic oxidation of benzylamine under mild conditions (at 25 °C, in air and without adding an additional sacrificial reagent, redox mediator and photosensitizer). [ABSTRACT FROM AUTHOR]

Electrochemical conversion of CO2 to valuable fuels is appealing for CO2 fixation and energy storage. The Cu‐based catalysts feature unique superiorities, but achieving high ethylene selectivity is still restricted. In this study, we propose the anchoring of an ionic liquid (IL) on a Cu electrocatalyst for improving the electrochemical CO2 reduction to ethylene. In a water‐based electrolyte and a commonly used H‐type cell, a high ethylene Faradaic efficiency of 77.3 % was achieved at −1.49 V (vs. RHE). Experimental and theoretical studies reveal that an IL can modify the electronic structure of a Cu catalyst through its interaction with Cu, making it more conducive to *CO dimerization for ethylene formation. [ABSTRACT FROM AUTHOR]

Using solar energy to realize CO2 reduction and benzylamine oxidation is of great importance. Here, we design Zn-Bi2WO6 microflowers catalyst, which can simultaneously reduce CO2 to CO and oxidize benzylamine to N-benzylbenzaldimine with high activities and selectivities in a simple photocatalytic system. [ABSTRACT FROM AUTHOR]

Herein, we demonstrate the highly efficient photocatalytic sulfide oxidation reaction under mild conditions, i.e. in air, at room temperature and in the absence of a sacrificial reagent, co-catalyst or redox mediator, by using ultrathin C,N-TiO2 nanosheets as a photocatalyst. [ABSTRACT FROM AUTHOR]

Here we demonstrate that the utilization of 2,4,6-tris(4-pyridyl)pyridine (tpy) for metal–organic framework modification can greatly improve the photocatalytic performance for CO2 reduction. The electron-donating nature of tpy enables the charge transfer effect, which induces strong CO2 binding affinity, facilitates *COOH formation and promotes CO2-to-CO conversion. [ABSTRACT FROM AUTHOR]

It is of great importance to develop facile strategies to synthesize catalysts with desirable compositions and structures for high-performance photocatalytic hydrogen generation. In this work, we put forward an ionic liquid assisted one-pot route for the synthesis of heteroatom-doped Pt/TiO2 composite material. This route is simple, environmentally benign and adjustable owing to the designable properties of ionic liquids. The as-synthesized Pt/TiO2 nanocrystals exhibit high activity and stability for the photocatalytic hydrogen generation under simulated solar irradiation. This method can be easily applied to the synthesis of various kinds of metal/TiO2 composites doped with desirable heteroatoms (e.g., F, Cl, Br, etc). [ABSTRACT FROM AUTHOR]

Herein, we demonstrate for the first time the one-step synthesis of ultrathin α-Co(OH)2 nanomeshes by an imidazole-directed route. The α-Co(OH)2 nanomeshes combine the advantages of ultrathin thickness (3 nm), small mesopores (3.7 nm), large specific surface area (181.1 m2 g−1) and high surface oxygen vacancy density, which exhibit excellent electrocatalytic performance for the oxygen evolution reaction. [ABSTRACT FROM AUTHOR]

The acidic electrocatalytic conversion of CO 2 to multi-carbon (C 2+ ) oxygenates is of great importance in view of enhancing carbon utilization efficiency and generating products with high energy densities, but suffering from low selectivity and activity. Herein, we synthesized Ag-Cu alloy catalyst with highly rough surface, by which the selectivity to C 2+ oxygenates can be greatly improved. In a strongly acidic condition (pH=0.75), the maximum C 2+ products Faradaic efficiency (FE) and C 2+ oxygenates FE reach 80.4 % and 56.5 % at -1.9 V versus reversible hydrogen electrode, respectively, with a ratio of FE C2+ oxygenates to FE ethylene up to 2.36. At this condition, the C 2+ oxygenates partial current density is as high as 480 mA cm -2 . The in situ spectra, control experiments and theoretical calculations indicate that the high generation of C 2+ oxygenates over the catalyst originates from its large surface roughness and Ag alloying., (© 2024 Wiley-VCH GmbH.)

The photocatalytic oxidation of biomass-derived benzyl alcohol provides a promising way for the synthesis of benzoic acid, which is an important intermediate with wide applications. To improve the efficiency of photocatalytic benzyl alcohol oxidation to benzoic acid is of great interest. In this work, we propose the utilization of NH 2 -UiO-66-ID-Fe catalyst for photocatalytic oxidation of benzyl alcohol to benzoic acid, where NH 2 -UiO-66 is a typically used metal-organic framework, ID is indole-2,3-dione (ID) that has biocompatibility, light absorption property and can be covalently combined with amino-functionalized substances. The NH 2 -UiO-66-ID-Fe catalyst exhibits improved light absorption and photo-generated electron-hole separation ability compared with NH 2 -UiO-66. The photocatalytic performance of NH 2 -UiO-66-ID-Fe was examined for the oxidation of bio-based benzyl alcohol under mild conditions of air atmosphere, room temperature and no additive or additional oxidant involved. The results show that the conversion of benzyl alcohol and the selectivity to benzoic acid could both reach over 99 % in 6 h, and the generation rate of benzoic acid per gram of catalyst is 3.36 mmol g -1  h -1 . The reaction mechanism was detected by radical trapping method and in situ electron paramagnetic resonance. This study presents an efficient and environmentally benign avenue for the synthesis of carboxylic acid compounds., (© 2024 Wiley-VCH GmbH.)

We demonstrate the electrochemical conversion of carbon dioxide into multi-carbon products catalyzed by Cu/Cu 2 O nanocrystals, with a maximum C 2+ faradaic efficiency of 75% in 0.10 M K 2 SO 4 aqueous solution at -2.0 V versus Ag/AgCl and a partial current density of 34 mA cm -2 .

Here, SnS 2 /polypyrrole (PPy) was synthesized, which shows high catalytic activity for the photocatalytic oxidation of benzylamine under mild conditions (at 25 °C, in air and without adding an additional sacrificial reagent, redox mediator and photosensitizer).

Low-dimensional metal-organic frameworks (MOFs) exhibit enhanced properties compared with three-dimensional (3D) geometry MOFs in many fields. In this work, we demonstrate the synthesis of Cu 3 (BTC) 2 (BTC = benzene-1,3,5-tricarboxylate) nanoflakes in a binary solvent of ionic liquid (IL) and water. Such a MOF architecture has a high surface area and abundant unsaturated coordination metal sites, making them attractive for adsorption and catalysis. For example, in catalyzing the oxidation reactions of a series of alcohols, the Cu 3 (BTC) 2 nanoflakes exhibit a high performance that is superior to Cu 3 (BTC) 2 microparticles synthesized in a conventional solvent. Experimental and theoretical studies reveal that the IL accelerates the crystallization of Cu 3 (BTC) 2 , while water plays a role in stripping the Cu 3 (BTC) 2 blocks that are formed at an early stage through its attack on the crystal plane of Cu 3 (BTC) 2 . Such an in situ crystallization-exfoliation process that uses an IL/water solvent opens a new route for producing low-dimensional MOFs.

Herein, we demonstrated a highly efficient photocatalytic sulfide oxidation reaction at ambient conditions without a sacrificial reagent or redox mediator, by using Co(NO 3 ) 2 /covalent organic framework nanoparticles as a photocatalyst.