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An efficient g-C3N4/BiVO4 heterojunction photocatalyst is constructed with BiVO4 networks decorated by discrete g-C3N4 nano-islands with controllable coverage. The as-synthesized g-C3N4/BiVO4 photo-catalyst shows superior visible light photocatalytic activity. The enhanced photocatalytic activity can be ascribed to increased charge separation efficiency, separated redox reaction sites, fully exposed reactive interfaces, and excellent visible light response of g-C3N4/BiVO4 composite.

Abstract-Recently, lattice reduction has been widely used for signal detection in multiinput multioutput (MIMO) communications. In this paper, we present three novel lattice reduction algorithms. First, using a unimodular transformation, a significant improvement on an existing Hermite-Korkine-Zolotareff-reduction algorithm is proposed. Then, we present two practical algorithms for constructing Minkowski-reduced bases. To assess the output quality, we compare the orthogonality defect of the reduced bases produced by LLL algorithm and our new algorithms, and find that in practice Minkowski-reduced basis vectors are the closest to being orthogonal. An error-rate analysis of suboptimal decoding algorithms aided by different reduction notions is also presented. To this aim, the proximity factor is employed as a measurement. We improve some existing results and derive upper bounds for the proximity factors of Minkowski-reduction-aided decoding (MRAD) to show that MRAD can achieve the same diversity order with infinite lattice decoding (ILD).

Efficient charge separation and light absorption are crucial for solar energy conversion over solid photocatalysts. This paper describes the construction of Pt@TiO @In O @MnO mesoporous hollow spheres (PTIM-MSs) for highly efficient photocatalytic oxidation. TiO -In O double-layered shells were selectively decorated with Pt nanoparticles and MnO on the inner and outer surfaces, respectively. The spatially separated cocatalysts drive electrons and holes near the surface to flow in opposite directions, while the thin heterogeneous shell separates the charges generated in the bulk phase. The synergy between the thin heterojunctions and the spatially separated cocatalysts can simultaneously reduce bulk and surface/subsurface recombination. In O also serves as a sensitizer to enhance light absorption. The PTIM-MSs exhibit high photocatalytic activity for both water and alcohol oxidation.

The removal of hydrogen sulfide (H2S) is essential in various industry applications such as purification of syngas for avoiding its corrosion and toxicity to catalysts. The design of adsorbents that can bear corrosion of H2S and overcome the competitive adsorption from carbon dioxide (CO2) is a challenge. To obtain insight into the stability and adsorption mechanism of metal–organic frameworks (MOFs) during the H2S separation process, 11 MOF-based materials were employed for H2S capture from CO2. Density functional theory, molecular dynamic studies, and dynamic separation experiments were used to investigate selective H2S/CO2 separation. Most of these MOFs showed one-off high capacity and selectivity to H2S. Complete reversible physical adsorption was proven on Mg-MOF-74, MIL-101­(Cr), UiO-66, ZIF-8, and Ce-BTC. Incomplete reversible adsorption occurred on UiO-66­(NH2). Disposable chemical reaction happened on HKUST-1, Cu-BDC­(ted)0.5, Zn-MOF-74, MIL-100­(Fe) gel, and MOF-5. Using breakthrough experiments, UiO-66, Mg-MOF-74, and MIL-101­(Cr) were screened out to present promising performance on the H2S capture. The present study is useful to identify and design suitable MOF materials for high-performance H2S capture and separation.

This paper describes the construction of reduced graphene oxide (rGO)/BiVO 4 composites with maximized interfacial coupling and their application as visible light photocatalysts. Thin rGO sheets (<5 nm) could completely cover BiVO 4 polyhedrons with highly active (040) facets exposed through an evaporation-induced self-assembly process. In addition to the increased surface adsorption effect of rGO, a considerable enhancement of the photoactivity of BiVO 4 has been demonstrated through the degradation of methylene blue upon the covering of rGO. The improved photocatalytic activity is attributed to the formation of well-defined rGO/BiVO 4 interfaces, which greatly enhances the charge separation efficiency.

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