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The photocatalytic CO2 reduction reaction (CRR) holds great promise for curbing anthropogenic CO2 emissions, though boosting photocatalyst activity and tuning product selectivity remain key priorities. Herein, isolated Ni single atoms dispersed on defect rich zirconia (Ni‐SA‐x/ZrO2) are identified as a very promising photocatalyst for CRR under Xe lamp irradiation, showing good activity and CO selectivity in the absence of added sacrificial agents or sensitizers. Due to an abundance of accessible nickel single atomic sites, the optimized photocatalyst affords CO at a rate of 11.8 µmol g−1 h−1 (92.5% selectivity). Experimental and theoretical investigations determine that the atomically dispersed Ni sites lower the energy barrier for CO2 to CO conversion via an adsorbed COOH intermediate, while also suppressing H2 desorption in the competing water splitting reaction. The Ni single atom sites thus simultaneously promote CO2 conversion and CO selectivity, thus offering valuable new insights for the future design of improved metal single‐atom catalysts for CRR. [ABSTRACT FROM AUTHOR]

Photocatalytic CO 2 reduction holds promise as a future technology for the manufacture of fuels and commodity chemicals. However, factors controlling product selectivity remain poorly understood. Herein, we compared the performance of a homologous series of Zn-based layered double hydroxide (ZnM-LDH) photocatalysts for CO 2 reduction. By varying the trivalent or tetravalent metal cations in the ZnM-LDH photocatalysts (M = Ti4+, Fe3+, Co3+, Ga3+, Al3+), the product selectivity of the reaction could be precisely controlled. ZnTi-LDH afforded CH 4 as the main reduction product; ZnFe-LDH and ZnCo-LDH yielded H 2 exclusively from water splitting; whilst ZnGa-LDH and ZnAl-LDH generated CO. In-situ diffuse reflectance infrared measurements, valence band XPS and density function theory calculations were applied to rationalize the CO 2 reduction selectivities of the different ZnM-LDH photocatalysts. The analyses revealed that the d -band center (ε d) position of the M3+ or M4+ cations controlled the adsorption strength of CO 2 and thus the selectivity to carbon-containing products or H 2. Cations with d -band centers relatively close to the Fermi level (Ti4+, Ga3+ and Al3+) adsorbed CO 2 strongly yielding CH 4 or CO, whereas metal cations with d -band centers further from the Fermi level (Fe3+ and Co3+) adsorbed CO 2 poorly, thereby yielding H 2 only (from water splitting). Our findings clarify the role of trivalent and tetravalent metal cations in LDH photocatalysts for the selective CO 2 reduction, paving new ways for the development of improved LDH photocatalyst with high selectivities to specific products. [ABSTRACT FROM AUTHOR]

We herein demonstrate the uniform porous hierarchical plate-like BiOCl/2D networks Bi 2 S 3 heterostructures realized by a facile two-step hydrothermal technique. The synthesis involved an anion exchange process by reacting pre-synthesized BiOCl irregular octagonal nanoplates with Na 2 S 2 O 3 ·5H 2 O in an aqueous solution. The experiment results revealed that the 3D plate-like heterostructures were composed of internal BiOCl and outside networks interwoven by 1D Bi 2 S 3 nanorods. Interestingly, the heterostructures had almost the same thickness and the bigger length compared to the precursor BiOCl. We proposed the possible formation mechanism of the composites which involved selective ion-exchange reaction, the following Ostwald ripening process and epitaxial growth. And the crystal lattice matching between the a- or b-axis of tetragonal BiOCl (a = b = 3.89 Å) and the a-axis of orthorhombic Bi 2 S 3 (a = 3.981 Å) could be responsible for the in-situ topotactic transformation. Due to the formation of hetero-nanostructures, the unique spatial architecture features and the existence of oxygen vacancies, the BiOCl/Bi 2 S 3 composites exhibited significantly extended photo-responsive range and improved photocatalytic activity for reduction of Cr VI under visible-light irradiation. Moreover, the possible mechanism of photocatalysis process was investigated. Our work is expected to inspire further attempts for hierarchical and unconventional hetero-nanostructures with unique spatial architecture, which is very promising for photocatalysis and other applications. [ABSTRACT FROM AUTHOR]

A series of BiOBr nanosheets with tunable exposing proportion of (0 1 0) facets had been synthesized. In the synthesis process, different n -alcohols are used, which not only promote the exposure of (0 1 0) facets, but also modulate the size and thickness of these BiOBr nanosheets in a wide range. Furthermore, these nanosheets showed an efficient photodegradation activity for salicylic acid (SA) and Rhodamine B (RhB). By comparison, the sample prepared in n -hexanol possessed the highest photocatalytic activity than those synthesized in n -butanol and methanol, respectively. This excellent photocatalytic activity was attributed to the thin lamellar thickness and the exposure of (0 1 0) facets, which facilitated the separation of photoinduced electrons and holes. [ABSTRACT FROM AUTHOR]

Halide anion-doped bismuth terephthalate hybrids were synthesized using a facile solvothermal method. Four series of hybrids doped with halide anions X− (F−, Cl−, Br− and I−) were produced by varying the molar ratios ( n) of X− relative to Bi(NO3)3 ( n = 0.25, 0.5, 0.75 and 1) in dimethylformamide solution. The results indicated that 0.25 equiv. of different halide anion-doped bismuth terephthalate hybrids, especially BiBDC-Cl(0.25) and BiBDC-Br(0.25), exhibited excellent photocatalytic activity under visible light and UV light irradiation. They also exhibited excellent adsorption performance for Rhodamine B which could be attributed to high surface areas and negative charge on the surface of the catalysts. Moreover, the degradation of Rhodamine B under visible light irradiation is a photosensitization process and •O2− is the most important active species. The halide anion-doped bismuth terephthalate hybrids are promising photocatalysts for removal of organic pollutants. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

• Photocatalytic bacteria inactivation over air-water-catalyst triphase systems. • Direct observation of wettability-controlled interface structures. • 18 times higher H 2 O 2 generation rate than the corresponding diphase system. • Two orders of magnitude reduced colony concentration within 30 min irradiation. • Applicable in the antibacterial of atmosphere-connected water bodies. Antibacterial technology based on photo-generated reactive oxygen species (ROS) represents a promising strategy for antibiotic-resistant bacteria inactivation, but often results in poor activity due to the limited O 2 solubility in traditional water-catalyst diphase system. In this work, we develop an air-water-catalyst triphase system to explore the superiority of air phase-supplied O 2 for the enhancement of ROS generation and Klebsiella pneumoniae (KPN) inactivation efficiencies. Using P25-TiO 2 as model photocatalysts, we demonstrate that Wenzel-Cassie coexistent wetting state is the most conducive for photocatalytic ROS generation, offering a H 2 O 2 generation rate of 1003 ± 52 μM h−1, which is 18 times higher than corresponding diphase system. It also affords an over two orders of magnitude reduced KPN colony concentration within 30 min irradiation, achieving over 99 % light-triggered removal efficiency. The advantages of triphase system for photocatalytic bacterial inactivation will inspire the development of efficient photocatalytic antibacterial systems in atmosphere-connected water bodies. [ABSTRACT FROM AUTHOR]

The development of Fe single‐atom catalysts (Fe SACs) with abundant, accessible Fe sites is a key step toward enhancing the efficiency of the oxygen reduction reaction (ORR) in proton exchange membrane fuel cells (PEMFCs). In this study, Zn4O(1,4‐benzenedicarboxylate)3 (MOF‐5), which has a 3D microporous cubic structure, is used as the precursor to prepare highly‐porous carbon (denoted as C‐MOF‐5) with an ultrahigh specific surface area (2751 m2 g–1) and high external surface area (1651 m2 g–1). C‐MOF‐5 is demonstrated as an effective carbon support to yield Fe SAC‐MOF‐5 with a large amount of accessible FeNx sites (2.35 wt%). Fe SAC‐MOF‐5 delivers a half‐wave potential of 0.83 V (vs RHE) in a 0.5 m H2SO4 electrolyte, and achieves a peak power density of 0.84 W cm–2 in a 0.2 MPa H2‐O2 PEMFC. This excellent performance originates from the ultrahigh specific surface area of C‐MOF‐5 for the formation of a high density of single Fe atoms, and high external surface area for the increased exposure of active sites. This work may inspire the rational design of metal single‐atom catalysts derived from a wider range of MOF precursors with ultrahigh specific area to improve the performance of the oxygen reduction reaction in PEMFCs. [ABSTRACT FROM AUTHOR]

Quantum-sized BiOCl in the cage-like pores of SBA-16 have been prepared by impregnation method. The average diameter of BiOCl obviously decreases to 6.1 nm due to the confinement effect from the framework of SBA-16. Compared to the bulk BiOCl, the quantum-sized BiOCl in the cage-like pores of SBA-16 possesses a larger bandgap (3.35 eV), and the quantum confinement effect simultaneously result in an elevated electron transport ability and enhanced redox ability of charge carriers. The as-prepared BiOCl@SBA-16 photocatalysts exhibit high activity toward degradation of methyl orange (MO) under simulated sunlight irradiation. [ABSTRACT FROM AUTHOR]

The key means to improve the performance of lithium–sulfur batteries (LSBs) is to reduce the internal resistance by building an electronic/ionic pathway and to accelerate the conversion kinetics of lithium polysulfides (LiPSs) through modulation of interface functions. Herein, inspired by a grass root system, a flexible hierarchical CNF‐CNT (carbon nanofiber‐carbon nanotube) membrane decorated with Co‐doped NiS2 nanoparticles (Co‐NiS2@CNF‐CNT) is designed as an interlayer for LSBs, in which the in situ grown CNTs (root hairs) are wound on CNF (roots). Density functional theory (DFT) calculations show that Co doping introduces electron‐deficient regions at the doping sites in NiS2, thus improving chemical adsorption and catalytic activities toward LiPSs. The cell pairs with the Co‐NiS2@CNF‐CNT interlayer exhibit a high rate performance of 951.4 mAh g−1 at 3 C, a reversible capacity of 944.1 mAh g−1 after 500 cycles at 0.2 C, and a prolonged cycle life of 3000 cycles at 5 C. More importantly, an areal capacity of 7.96 mAh cm−2 is achieved with a sulfur loading of 9.6 mg cm−2. This work provides a strategy for enhancing the electrochemical performance of LSBs by combining 3D hierarchical conductive skeletons and electron‐deficient functional adsorption and catalysis materials. [ABSTRACT FROM AUTHOR]

• CuTIA with high CO 2 uptake served as a bifunctional catalyst for conversion. • CuTIA converted CO 2 into CH 4 with high yield and selectivity under visible light. • CuTIA drove CO 2 cycloaddition with epoxides into cyclic carbonates with high yield. Highly efficient conversion of CO 2 into valuable chemicals using green chemical reactions is attractive to the alleviation of global warming. Developing active catalysts with high selectivity remains challenging and is still in pursuit. Herein, a Cu-based metal−organic framework was successfully synthesized by a facile method and denoted as CuTIA. The obtained CuTIA with rich Lewis acid/base sites exhibited enhanced CO 2 affinity and served as a bifunctional catalyst for CO 2 conversion. To be specific, CuTIA converted CO 2 into CH 4 (103.78 μmol g−1 h−1) with a selectivity of 100 % under visible light irradiation. Besides, CuTIA drove CO 2 cycloaddition reaction with epoxides to produce cyclic carbonates with a yield almost 100 % under mild conditions. This study provides a new perspective in the fabrication of bifunctional catalysts for enhancing CO 2 conversion. A Cu-based MOF is constructed and employed as a bifunctional catalyst for photocatalytic CO 2 reduction and CO 2 cycloaddition with epoxides with high selectivity. [Display omitted] [ABSTRACT FROM AUTHOR]

The decay of lithium–sulfur (Li–S) batteries is mainly due to the shuttle effect caused by intermediate polysulfides (LiPSs). Herein, a multiple confined cathode architecture is prepared by filling graphitized Pinus sylvestris with carbon nanotubes and defective LaNiO3−x (LNO‐V) nanoparticles. The composite electrode with high areal sulfur loading of 11.6 mg cm−2 shows a high areal specific capacity of 8.5 mAh cm−2 at 1 mA cm−2 (0.05 C). Both experimental results and theoretical calculations reveal that this unique structure not only provides physical restriction on LiPSs within microchannels but also offers strong chemical immobilization and catalytic conversion of LiPSs attributed to the spin density around oxygen vacancies of LaNiO3−x. These oxygen vacancies elongate the SS and LiS bonds and make them easy to break. Furthermore, the lengthwise channels derived from cytoderm restrict the transverse diffusion of polysulfides, leading to a uniform areal current and thus homogeneous lithium infiltration. This suppresses the corrosion of the lithium anode due to polysulfides confinement. The discovery of the multiple confined structure that provides chemical adsorption, fast diffusion, and catalytic conversion for polysulfides can broaden the application of biomass materials and offer a new strategy to achieve robust Li–S batteries. [ABSTRACT FROM AUTHOR]

Construction of heterogeneous transmission interfaces that spatially separate Coulomb-bound electron-hole pairs in semiconductors allows exceptional control over optoelectronic properties, thereby enhancing the efficiency of solar energy conversion. In this study, we propose an effective photocatalyst for full water splitting named MS/BOC-x/Pd, comprising atomic layer of MoS 2 bonded to defect-rich BiOCl, and a non-plasmonic Pd oxidation co-catalyst is exclusively assembled on the sides to form a strong electronic coupling and maximize the trapping of holes. The presence of the Mo-S-Bi motif promotes rapid charge migration, resulting in impressive rates of H 2 and O 2 formation (165 and 9.17 μmol g−1 h−1, respectively), without the requirement of sacrificial agents or sensitizers. Through experimental and theoretical investigations, we discovered that the occupation of sulfur atoms in oxygen vacancies extends the overlap of surface charges, thereby facilitating the separation of inner/interfacial electron-hole pairs. The Mo-S-Bi bond provides directional guidance for charge transfer to the surface redox sites. These findings provide valuable insights for the future design of highly efficient photocatalysts for solar energy conversions. [Display omitted] • MS/BOC-Pd photocatalysts with well-designed charge transport channels were successfully constructed. • The atomic-level migration pathway(s) pertinent to water splitting have been systematically elucidated. • DFT calculations confirmed that the Mo-S-Bi configuration is optimal for charge migration. • Improved performance of photochemical conversion properties. [ABSTRACT FROM AUTHOR]

The discovery of improved chemical processes for CO and CO2 hydrogenation to valuable hydrocarbon fuels and alcohols is of paramount importance for the chemical industry. Such technologies have the potential to reduce anthropogenic CO2 emissions by adding value to a waste stream, whilst also reducing our consumption of fossil fuels. Current thermal catalytic technologies available for CO and CO2 hydrogenation are demanding in terms of energy input. Various alternative technologies are now being developed for COx hydrogenation, with solar-driven processes over two-dimensional (2D) and 2D-related composite materials being particularly attractive due to the abundance of solar energy on Earth and also the high selectivity of defect-engineered 2D materials towards specific valuable products under very mild reaction conditions. This review showcases recent advances in the solar-driven COx reduction to hydrocarbons over 2D-based materials. Optimization of 2D catalyst performance demands interdisciplinary research that embraces catalyst electronic structure manipulation and morphology control, surface/interface engineering, reactor engineering and density functional theory modelling studies. Through improved understanding of the structure–performance relationships in 2D-related catalysts which is achievable through the application of modern in situ characterization techniques, practical photo/photothermal/photoelectrochemical technologies for CO and CO2 reduction to high-valuable products such as olefins could be realized in the not-too-distant future. [ABSTRACT FROM AUTHOR]

As an anode material for lithium ion batteries (LIBs), Bi 2 S 3 possesses high redox activity and theoretical capacity. However, severe volume variation (alloying/dealloying processes) and active sulfide loss (dissolution of polysulfides) during cycling always result in rapid capacity degradation. Thus, we fabricated MOF-derived Bi 2 S 3 hybrid nanofibers coated by organic framework via facile polymerization and sulfidation processes. Such unique coating nanolayers derived from the cross-linked organic framework based on the Bi-MOF (CAU-17) can effectively tolerate the volume expansion and active sulfide loss, thus leading to excellent cycling stability (1059 mAh g−1 at 0.1 A g−1 after 100 cycles, 1108 mAh g−1 at 1.0 A g−1 after 500 cycles), and rate performance (478 mAh g−1 at 10 A g−1). This study offers a hopeful anode for highly efficient Li-ion storage, and a simple and low-energy-consuming strategy to improve the electrochemical performance of active materials. [Display omitted] • MOF-derived Bi 2 S 3 was prepared by a simple sulfidation process. • Bi-MOF-derived coating layer can effectively tolerate the active sulfide loss. • The MOF-derived Bi 2 S 3 hybrid showed an excellent reversible capacity. [ABSTRACT FROM AUTHOR]