Ultrathin W18O49 Nanowires with Diameters below 1 nm: Synthesis, Near-Infrared Absorption, Photoluminescence, and Photochemical Reduction of Carbon Dioxide

Dual-plasmon-enhanced nitrophenol hydrogenation over W18O49–Au heterostructures studied at the single-particle level

The dual-plasmonic W18O49–Au heterostructure exhibited enhanced catalytic performance in nitrophenol hydrogenation. The HEI process and coupling effect were demonstrated by single-particle spectroscopy and FDTD simulation.

N,Fe-Doped Carbon Dot Decorated Gear-Shaped WO3 for Highly Efficient UV-Vis-NIR-Driven Photocatalytic Performance

The development of efficient and non-toxic photocatalysts with a full spectrum response is a primary strategy in the area of photocatalytically mediated pollutant elimination. Herein, we report the preparation of novel nitrogen and iron co-doped carbon dots/gear-shaped WO3 (N,Fe-CDs/G-WO3) with significantly improved broad-spectrum utilization. Characterization results demonstrated that the gear-shaped G-WO3, decorated by N,Fe-CDs with excellent electron transfer/reservoir properties, possessed abundant oxygen vacancies, had large specific surface areas, had multiple light-reflections and had a narrow band gap. As a result, the N,Fe-CDs/G-WO3 composite exhibited excellent photocatalytic activity towards the degradation of water contaminants under full spectrum irradiation. For example, the photodegradative efficiencies of rhodamine B (RhB) reached 81.4%, 97.1%, and 75% in 2 h, under ultraviolet, visible, and near-infrared (UV, vis, and NIR) light irradiation, respectively. Moreover, the N,Fe-CDs/G-WO3 composite also exhibited an outstanding photocatalytic degradation efficiency for other dyes, pharmaceuticals, and personal care products (PPCPs) like methylene blue (MB), ciprofloxacin (CIP), tetracycline hydrochloride (TCH), and oxytetracycline (OTC) (91.1%, 70.5%, 54.5%, and 47.8% in 3 h, respectively). The radical trapping experiments indicated that h+ and ·OH were the main reactive oxidative species (ROS), and the conversion between Fe (III) and Fe (II) played a key role in the photocatalytic reactions. Such a N,Fe-CD decorated material with brilliant photocatalytic activity has tremendous potential for application in environmental remediation.

From CO2methanation to ambitious long-chain hydrocarbons: alternative fuels paving the path to sustainability

Comprehensive insight into the thermochemical, photochemical and electrochemical reduction of CO₂to methane and long-chain hydrocarbons as alternative fuels.

Ultra-large optical modulation of a size-tunable flexible electrochromic honeycomb mesoporous tungsten oxide film

A size tunable flexible electrochromic honeycomb mesoporous tungsten oxide film with ultra-large optical modulation is achieved by breath figure self-assembly of polymer-like ultrathin W₁₈O₄₉ nanowires.

Emerging Applications of Plasmons in Driving CO2 Reduction and N2 Fixation

The photochemical production of fuels using sunlight is an innovative way for meeting the quickly increasing energy demands. One of the largest challenges is to develop high-performance photocatalysts that can meet the requirements of practical applications. Owing to their intriguing localized surface plasmon resonances, noble metal nanoparticles and nanostructures show a great potential for enhancing the photocatalytic efficiency and thereby have attracted rapidly growing interest recently. Here, for the first time, the latest achievements in the utilization of plasmons in driving CO₂ reduction and N₂ fixation into high-value products are comprehensively described. The involved plasmonic enhancement mechanisms in the two types of reactions are fully illustrated. A particular emphasis is given to the outlook on the direction and prospects for future work in this topic.

Ordered WO3−x nanorods: facile synthesis and their electrochemical properties for aluminum-ion batteries

WO_3−x nanorods are successfully synthesized via a facile hydrothermal process combined with a subsequent thermal reduction process, exhibiting two discharge plateaus of about 1.4 V and 1.0 V as cathodes for aluminum-ion batteries.

Organic Solar Cells Based on WO2.72 Nanowire Anode Buffer Layer with Enhanced Power Conversion Efficiency and Ambient Stability

Tungsten oxide as an alternative to conventional acidic PEDOT:PSS has attracted much attention in organic solar cells (OSCs). However, the vacuum-processed WO₃ layer and high-temperature sol-gel hydrolyzed WO_X are incompatible with large-scale manufacturing of OSCs. Here, we report for the first time that a specific tungsten oxide WO_2.72 (W₁₈O₄₉) nanowire can function well as the anode buffer layer. The nw-WO_2.72 film exhibits a high optical transparency. The power conversion efficiency (PCE) of OSCs based on three typical polymer active layers PTB7:PC₇₁BM, PTB7-Th:PC₇₁BM, and PDBT-T1:PC₇₁BM with nw-WO_2.72 layer were improved significantly from 7.27 to 8.23%, from 8.44 to 9.30%, and from 8.45 to 9.09%, respectively compared to devices with PEDOT:PSS. Moreover, the photovoltaic performance of OSCs based on small molecule p-DTS(FBTTh₂)₂:PC₇₁BM active layer was also enhanced with the incorporation of nw-WO_2.72. The enhanced performance is mainly attributed to the improved short-circuit current density (J_sc), which benefits from the oxygen vacancies and the surface apophyses for better charge extraction. Furthermore, OSCs based on nw-WO_2.72 show obviously improved ambient stability compared to devices with PEDOT:PSS layer. The results suggest that nw-WO_2.72 is a promising candidate for the anode buffer layer materials in organic solar cells.

Robust electrocatalysts from metal doped W18O49 nanofibers for hydrogen evolution

Electrocatalysts from metal doped W₁₈O₄₉ nanofibers are robust, high-efficiency and stable for hydrogen evolution.

Preparation of 2D hydroxyl-rich carbon nitride nanosheets for photocatalytic reduction of CO2

The nanosheet exhibits better visible-light photocatalytic activity than bulk g-C₃N₄ due to nanosheet nature and presence of more hydroxyl groups.

Photocatalytic reduction of CO2 on TiO2 and other semiconductors

Rising atmospheric levels of carbon dioxide and the depletion of fossil fuel reserves raise serious concerns about the ensuing effects on the global climate and future energy supply. Utilizing the abundant solar energy to convert CO2 into fuels such as methane or methanol could address both problems simultaneously as well as provide a convenient means of energy storage. In this Review, current approaches for the heterogeneous photocatalytic reduction of CO2 on TiO2 and other metal oxide, oxynitride, sulfide, and phosphide semiconductors are presented. Research in this field is focused primarily on the development of novel nanostructured photocatalytic materials and on the investigation of the mechanism of the process, from light absorption through charge separation and transport to CO2 reduction pathways. The measures used to quantify the efficiency of the process are also discussed in detail.

Defective TiO2 with oxygen vacancies: synthesis, properties and photocatalytic applications

Titanium dioxide (TiO2), as an important semiconductor metal oxide, has been widely investigated in the field of photocatalysis. The properties of TiO2, including its light absorption, charge transport and surface adsorption, are closely related to its defect disorder, which in turn plays a significant role in the photocatalytic performance of TiO2. Among all the defects identified in TiO2, oxygen vacancy is one of the most important and is supposed to be the prevalent defect in many metal oxides, which has been widely investigated both by theoretical calculations and experimental characterizations. Here, we give a short review on the existing strategies for the synthesis of defective TiO2 with oxygen vacancies, and the defect related properties of TiO2 including structural, electronic, optical, dissociative adsorption and reductive properties, which are intimately related to the photocatalytic performance of TiO2. In particular, photocatalytic applications with regard to defective TiO2 are outlined. In addition, we offer some perspectives on the challenge and new direction for future research in this field. We hope that this tutorial minireview would provide some useful contribution to the future design and fabrication of defective semiconductor-based nanomaterials for diverse photocatalytic applications.

Photocatalytic CO(2) reduction using non-titanium metal oxides and sulfides

Titanium dioxide (TiO2 ) is by far the most widely used photocatalyst both for the degradation of pollutants and in the field of renewable energies for the production of solar fuels. However, TiO2 has strong limitations in CO2 reduction, particularly under visible light irradiation. The flat-band potential of electrons in the conduction band of TiO2 is lower than that required for CO2 reduction and, therefore, it seems appropriate to develop and validate materials other than TiO2 . In addition, the photoresponse of TiO2 requires photons of wavelengths in the UV range shorter than 380 nm and strategies to implement a visible-light photoresponse on TiO2 by doping have not been completely satisfactory particularly because of problems in reproducibility and stability of the materials. For these reasons, we focus in this Review on semiconductors other than TiO2 that show photocatalytic activity in CO2 reduction. Attention has been paid to the irradiation conditions to put the productivity data into context. The role of co-catalyst and heterojunctions to increase the efficiency of charge separation is also discussed. Our aim is to describe the state of the art in the field of photocatalytic CO2 reduction using materials other than TiO2 , trying to trigger further research in this area.