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Three-dimensional reduced graphene oxide@SnO 2 @nitrogen-doped carbon (3DG@SnO 2 @N-C) composites are designed as high efficiency anode materials for lithium-ion batteries. The SnO 2 particle size, surface area and pore size distribution of the 3DG@SnO 2 @N-C could be simply controlled by altering the GO dosages. The optimized 3DG@SnO 2 @N-C electrode demonstrates a reversible capacity of 1349.5 mAh g -1 after 100 cycles at the current density of 100 mA g -1 . Based on the structural and electrochemical dynamic tests, the bi-functional N-doped carbon coating layer could serve as both conductive channel for electron transport and as buffer layer to alleviate the volume change of embedded SnO 2 NPs. In addition, the cross-linked conducting 3DG with porous structure attributes to the reduced electron transport and Li ion diffusion resistances, which finally leads to the enhanced cycling stability and rate performances., (Copyright © 2019 Elsevier Inc. All rights reserved.)

TiO 2 microsphere with tunable pore and chamber size are prepared by a simple solventhermal method and used as catalyst for the photocatalytic CO 2 reduction. It is found that the hollow microsphere with relative lower surface area of 73.8 m 2 g -1 exhibits increased pore size of 18.1 nm and cavity structure, leading to higher CO 2 diffusion coefficient of 5.40 × 10 -5 cm 2 s -1 compared with the solid and yolk/shell microspheres. Therefore, the hollow microsphere possesses more accessible sites for CO 2 adsorption, which finally gives rise to the enhanced CO production rate of 10.9 ± 0.7 μmol g -1 h -1 under simulated sunlight, which is respectively 1.6 and 1.4 times higher than that of solid and yolk/shell microspheres. Electron dynamic study further demonstrates that hollow microsphere shows the highest photocurrent density and the lowest charge recombination among three microspheres structure, which is attributed to the swift CO 2 diffusion providing fresh CO 2 molecules to rapidly scavenge the photo-generated electrons and finally leading to the excellence catalytic reduction performances. This method could be adopted as a general strategy to prepare high performance TiO 2 catalysts with desirable structural qualities for the photocatalytic CO 2 reduction under nature sunlight., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Janus shaped BiOCl/MoS 2 composites with two dimensional configuration are successfully prepared via a facile pulse ultrasonic assisted method, which spontaneously introduces oxygen vacancies on the BiOCl surface and builds well-defined heterojuction at the BiOCl/MoS 2 interfaces. The as-prepared BiOCl/MoS 2 composites possess reduced band gap and defect energy levels due to the incorporation of MoS 2 and the oxygen vacancies, which permits the enhanced light harvesting efficiency in the visible range. In addition, because of the formed BiS bonds at the BiOCl/MoS 2 interface, the composites demonstrate improved charge separation of the photo-generated carriers. Therefore, when used as photocatalyst for Rhodamine B photodegradation, the optimized composite demonstrates a degradation rate of 0.078 min -1 , which is much enhanced compared with that of pure BiOCl (0.052 min -1 ). Mechanism investigation indicates the degradation is a hole mediated process. In addition, the composite shows good stability and outstanding organic carbon removal efficiency, which could serve as a promising photocatalyst for water remediation under visible light., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Bi 2 WO 6 porous nanosheets (PNS) with different thickness were synthesized via one-pot hydrothermal method. The thickness of Bi 2 WO 6 nanosheets could be well controlled from ∼27 nm to ∼16 nm by adjusting the precursor concentration. In addition, the PNS exhibited porous structures, high surface area and high lattice coherence, which increased the number of catalytic sites and facilitated the charge migration within the sheet structure. The Cr(VI) reduction experiments showed that the photocatalytic activity was greatly affected by the thickness of the product and the optimal photocatalytic activity under visible light irradiation was achieved by BWO-3 with thickness of ∼18 nm. The photocatalytic ratio of Cr(VI) reduction for BWO-3 reached to ∼99.5% after 100 min visible light irradiation, which was higher than that of BWO (∼78%). Based on the optical and electrochemical measurements, BWO-3 had upshifted conduction band of 0.05 V, prolonged carriers' lifetime of 2.03 ns and decreased carriers' recombination efficiency compared to BWO. These results endowed BWO-3 with high photoreduction ability, increased transfer and separation efficiency of carriers, and thus enhanced the photoreduction activity., (Copyright © 2018 Elsevier Inc. All rights reserved.)