based on connecting central metal atoms/ clusters and organic ligands, have attracted considerable attention. [3][4][5] MOFs can be rationally designed by modifying their constituting metal atoms/clusters and organic ligands, allowing a control of their shapes and sizes. [6] Shapes are typically controlled by introducing modulators (cosolvents or surfactants) that preferentially adsorb onto specific crystal planes, consequently hampering their growth. Furthermore, the size can be adjusted by changing the solvent ratio or reaction time. For these reasons, MOFs are endowed with outstanding properties and potential applications, such as in sensors, [7] electrocatalysis, [8,9] and energy-storage devices. [10,11] The porous structure of MOFs makes them promising host materials to anchor sulfur in Li-S batteries, and this has attracted considerable attention because of their high theoretical capacity (1675 mAh g −1 ). [12,13] The main obstacle to impede commercialization of Li-S batteries is the shuttle effect, leading to an irreversible loss of sulfur during the discharge process. [14] At present, a variety of carbonaceous materials have been adopted as host materials to enable uniform dispersion of sulfur. [15] However, the physical confinement of lithium polysulfides (LPS, chemical formula: Li 2 S x , 4 ≤ x ≤ 8) in nonpolar carbonaceous materials is not sufficient to prevent Metal-organic frameworks (MOFs) with controllable shapes and sizes show a great potential in Li-S batteries. However, neither the relationship between shape and specific capacity nor the influence of MOF particle size on cyclic stability have been fully established yet. Herein, MIL-96-Al with various shapes, forming hexagonal platelet crystals (HPC), hexagonal bipyramidal crystals (HBC), and hexagonal prismatic bipyramidal crystals (HPBC) are successfully prepared via cosolvent methods. Density functional theory (DFT) calculations demonstrate that the HBC shape with highly exposed (101) planes can effectively adsorb lithium polysulfides (LPS) during the charge/discharge process. By changing the relative proportion of the cosolvents, HBC samples with different particle sizes are prepared. When these MIL-96-Al crystals are used as sulfur host materials, it is found that those with a smaller size of the HBC shape deliver higher initial capacity. These investigations establish that different crystal planes have different adsorption abilities for LPS, and that the MOF particle size should be considered for a suitable sulfur host. More broadly, this work provides a strategy for designing sulfur hosts in Li-S batteries.The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adma.202107836.

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The effect of defect on the photocatalytic and photoelectric performance of BiPO4 has been revealed. The bulk defects of BiPO4 such as bismuth vacancies(VBi), oxygen vacancies(VO) and so on were formed during the ball-milling process. These bulk defects of BiPO4 inhibited the separation of photo-generated charges greatly and thus reduced photocatalytic activity. Most of the bulk defects were repaired and the photocatalytic activity of BiPO4 was also recovered mostly via calcination and reflux. Reflux could repair the bulk defects of BiPO4 much better than calcination. The mechanism of the photocatalytic degradation of pollutants over BiPO4 was not changed by defects, and the main oxidation active species of BiPO4 is photo-generated hole.

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TiO2/g-C3N4 (TCN) thin film electrode was fabricated via a surface hybridization and dip-coating method. Phenol could be completely mineralized and the pollutants in coking wastewater could be degraded quickly by TCN under simulated solar light and electric field. The characteristics of the photoelectrocatalytic (PEC) degradation of phenol-containing coking wastewater were investigated under visible light, ultraviolet light and simulated solar irradiation. The results showed that phenol was degraded completely by the TCN-0.3 with a 1.5 V bias in 1.5 h under simulated solar irradiation with 100% TOC removal rate. 45% of the TOC for the coking wastewater was removed by the TCN-0.3 with a 1.5 V bias under 5.0 h simulated solar irradiation, which was 2.45 and 5.69 times as high as that of the pure TiO2 and g-C3N4, respectively. The surface hybrid heterojunction formed between TiO2 and g-C3N4 promotes the migration of the photogenerated electrons and holes and greatly improves the degradation efficiency with applied potential. The significant synergistic effect between the electrocatalytic and photocatalytic oxidation processes in PEC is conducive to electron-hole pair separation, producing the more active substances, such as © 2016. This manuscript version is made available under the Elsevier user license http://www.elsevier.com/open-access/userlicense/1.0/ 2 hydroxyl radicals, and increases the degree of degradation and mineralization of phenolic compounds.