Wuhan University of Technology

About: Wuhan University of Technology is a education organization based out in Wuhan, China. It is known for research contribution in the topics: Microstructure & Photocatalysis. The organization has 40384 authors who have published 36724 publications receiving 575695 citations. The organization is also known as: WUT.

Carbon-based H2-production photocatalytic materials

Abstract: Photocatalytic hydrogen production from water splitting is of promising potential to resolve the energy shortage and environmental concerns. During the past decade, carbon materials have shown great ability to enhance the photocatalytic hydrogen-production performance of semiconductor photocatalysts. This review provides a comprehensive overview of carbon materials such as CNTs, graphene, C60, carbon quantum dots, carbon fibers, activated carbon, carbon black, etc. in enhancing the performance of semiconductor photocatalysts for H2 production from photocatalytic water splitting. The roles of carbon materials including supporting material, increasing adsorption and active sites, electron acceptor and transport channel, cocatalyst, photosensitization, photocatalyst, band gap narrowing effect are explicated in detail. Also, strategies for improving the photocatalytic hydrogen-production efficiency of carbon-based photocatalytic materials are discussed in terms of surface chemical functionalization of the carbon materials, doping effect of the carbon materials and interface engineering between semiconductors and carbon materials. Finally, the concluding remarks and the current challenges are highlighted with some perspectives for the future development of carbon-based photocatalytic materials.

VO2 nanowires assembled into hollow microspheres for high-rate and long-life lithium batteries.

Abstract: Development of three-dimensional nanostructures with high surface area and excellent structural stability is an important approach for realizing high-rate and long-life battery electrodes. Here, we report VO2 hollow microspheres showing empty spherical core with radially protruding nanowires, synthesized through a facile and controllable ion-modulating approach. In addition, by controlling the self-assembly of negatively charged C12H25SO4– spherical micelles and positively charged VO2+ ions, six-armed microspindles and random nanowires are also prepared. Compared with them, VO2 hollow microspheres show better electrochemical performance. At high current density of 2 A/g, VO2 hollow microspheres exhibit 3 times higher capacity than that of random nanowires, and 80% of the original capacity is retained after 1000 cycles. The superior performance of VO2 hollow microspheres is because they exhibit high surface area about twice higher than that of random nanowires and also provide an efficient self-expansion a...

Defect-Rich Soft Carbon Porous Nanosheets for Fast and High-Capacity Sodium-Ion Storage

Abstract: DOI: 10.1002/aenm.201803260 lithium-ion batteries (LIBs) cannot meet the increasing requirement of large-scale energy storage due to the limited and high cost of lithium resources.[4,5] Other alkali metals (especially sodium and potassium) are recognized as alternatives to lithium owing to abundance of elemental source and geographical distribution.[6–8] While the lithium and sodium share common properties as alkali metals, the assumption of adapting the same electrode materials from LIBs to sodium-ion batteries (SIBs) is not always efficacious.[9–11] The intrinsically higher redox potential of Na+/Na compared with Li+/Li (−2.71 > −3.04 V vs standard hydrogen electrode) and the sluggish Na+ transport resulting from the larger radius of Na+ compared with Li+ (1.02 > 0.76 Å) directly affect the electrochemical performance.[10] As the most common anode for commercial LIBs, graphite exhibits superior reversible capacity (close to its theoretical capacity of 372 mAh g−1) as a result of consecutive migration of Li+ between layered structures to forming LiC6. Nevertheless, as demonstrated by previous reports, both the experiment carried out by Doeff et al.[14] and the theoretical calculation performed via Density Functional Theory studies by Wang et al.[15] in 2014 prove that it is hard to form sodium intercalated graphite compounds.[16,17] Only a small amount of Na+ can be stored in graphite, leading to the suppressed reversible capacity of ≈30 mAh g−1.[11,18,19] In contrast to the graphite, the nongraphitizable hard carbon and graphitizable nongraphitic soft carbon have attracted most attentions as anodes for SIBs on account of their high capacity.[20,21] The sodiation of hard carbon at room temperature has been first reported by Stevens and Dahn,[22] achieving a capacity of ≈300 mAh g−1. A insertion–absorption process named as “house of cards” has been introduced at the same time and further proved by in situ small angle X-ray scattering study, which ascribes the sodiation to insertion of Na-ions and metallic adsorption (deposition) into the pores.[23,24] After that, other sodium storage mechanisms of hard carbon called “absorption-insertion” and “absorptionfilling” have been introduced by Cao et al.[25] and Tarascon and co-workers,[26] respectively.[27] Considering the safety concern Soft carbon has attracted tremendous attention as an anode in rocking-chair batteries owing to its exceptional properties including low-cost, tunable interlayer distance, and favorable electronic conductivity. However, it fails to exhibit decent performance for sodium-ion storage owing to difficulties in the formation of sodium intercalation compounds. Here, microporous soft carbon nanosheets are developed via a microwave induced exfoliation strategy from a conventional soft carbon compound obtained by pyrolysis of 3,4,9,10-perylene tetracarboxylic dianhydride. The micropores and defects at the edges synergistically leads to enhanced kinetics and extra sodiumion storage sites, which contribute to the capacity increase from 134 to 232 mAh g−1 and a superior rate capability of 103 mAh g−1 at 1000 mA g−1 for sodium-ion storage. In addition, the capacitance-dominated sodium-ion storage mechanism is identified through the kinetics analysis. The in situ X-ray diffraction analyses are used to reveal that sodium ions intercalate into graphitic layers for the first time. Furthermore, the as-prepared nanosheets can also function as an outstanding anode for potassium-ion storage (reversible capacity of 291 mAh g−1) and dual-ion full cell (cell-level capacity of 61 mAh g−1 and average working voltage of 4.2 V). These properties represent the potential of soft carbon for achieving high-energy, high-rate, and low-cost energy storage systems.

Facile Synthesis of Monodisperse Porous ZnO Spheres by a Soluble Starch-Assisted Method and Their Photocatalytic Activity

Abstract: In this study, monodisperse porous ZnO spheres were fabricated by a facile and low-cost soluble-starch-assisted method. The as-obtained samples were characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), UV−vis diffuse reflectance spectroscopy (DRS), thermogravimetric and differential scanning calorimetry (TG−DSC), Fourier transform infrared (FTIR) spectroscopy, and Brunauer−Emmett−Teller (BET) analysis. The Raman spectra revealed that the uncalcined powders were composed of ZnO and starch. The BET analysis showed that mesopores (25 nm) and macropores (180 nm) coexisted in the typical porous ZnO spheres. The photocatalytic activities of the as-obtained ZnO samples were evaluated in the photocatalytic degradations of aqueous solutions of rhodamine B (RhB) and 4-nitrophenol (4-NP) at room temperature. A possible growth mechanism of the as-obtained porous ZnO spheres is also...