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Black phosphorus–carbon (BP–C) composite is a potential high‐energy anode material for lithium‐ion batteries (LIBs); however, the local stress concentration that occurs during lithiation/delithiation cycling leads to poor cycling performance. Herein, an electrochemically inactive TiP nanocrystal is used to reconstruct the BP–C composite via ball milling to form a BP–TiP–C multiphase structure with excellent lithium storage performance. The TiP intermediate optimizes the TiP–BP interface and relieves the local stress of the BP–TiP–C composite, thereby enhancing the electron transfer, structural stability, and utilization of the active material. This BP–TiP–C composite exhibits a high coulombic efficiency of 99.85%, an enhanced cyclic stability of 557.6 mAh g−1 after 1000 cycles with a 72.5% capacity retention at 2.0 A g−1, and an excellent rate performance of 548.2 mAh g−1 at 10.0 A g−1. Thus, this study not only provides a high‐energy BP–TiP–C material, but also offers new ideas for material synthesis to advance the research on BP‐based LIBs. [ABSTRACT FROM AUTHOR]

Understanding the charge reactions at the semiconductor/cocatalyst interface is of great interest for boosting photoelectrochemical water splitting since the charge transfer to water molecules is the sluggish one. Besides the dopants, porosity, or ion-penetration of the cocatalyst, the crystallinity of the cocatalyst may also influence the charge reactions at the interface. Herein, we prepared amorphous LaNiOx and crystalline La-doped NiO (c-LaNiOx) cocatalysts through photochemical decomposition and ion-exchange of Ni(OH)2 precipitation, respectively. Both lanthanum nickel oxides (LaNiOx) showed considerable improvement of hematite photoanodes. By using electrochemical impedance measurements, we confirmed that the catalyst could store photogenerated charges with reduced transfer resistance and passivate the surface state, resulting in the overall charge transfer rate enhancement. This study may lead to a chance to uncover the kinetic bottleneck with an efficient cocatalyst in well-controlled crystallinity in the future. [ABSTRACT FROM AUTHOR]

In order to alleviate the cyclic attenuation caused by the dissolution of poly-selenides in lithium/sodium storage devices, quantitative selenium was slowly evaporated on the surface of sodium citrate derived carbon (SCDC) at low temperature, and simultaneously the element Se was doped. Benefiting from the synergistic effects of the domain-limiting effect of embedded nanopores on Se nanoparticles and the stability of SCDC with Se doped during the embedding and stripping of Na ions, Se@C versus sodium metal exhibits high second specific capacity of 485 mAh·g−1 and unexpected stability at 0.1 A g−1 and 1 A g−1. Se@C versus lithium metal exhibits high second specific capacity of 1185 mAh·g−1 at 0.1 A g−1 and excellent stability. Together with the simple and application of synthesis method, Se@C composite is expected to become an anode material for large sodium/lithium storage devices. [ABSTRACT FROM AUTHOR]

Metal sulfides possess great potential for high-performance rechargeable lithium-ion batteries (LIBs). In this work, Bi2S3 with a lemongrass-like morphology was successfully synthesized via a facile solvothermal growth, followed by subsequent calcination. When employed as an anode material in lithium-ion batteries, the Bi2S3 showed a high reversible capacity, a better cycling stability, and a superior rate performance. A reversible capacity of 686 mAh g−1 was obtained at a current density of 200 mA g−1 after 150 cycles. When the current density was increased to 2000 mA g−1, Bi2S3 could deliver a capacity of more than 400 mAh g−1 after 500 cycles. This excellent electrochemical performance could be attributed to the featured structure of lemongrass-like Bi2S3, which can accommodate volume changes, shorten the ionic diffusion path, and enlarge the material/electrolyte contact area. [ABSTRACT FROM AUTHOR]

Abstract: The development of advanced photoelectrode materials for water splitting is as important as recycling to solve environmental problems. In this Communication, we report a facile hydrothermal epitaxial growth of hematite films from ferrioxalate solution, where the pH, isoelectric point and crystal nature of the substrates play key roles in the film growth. In a photoelectrochemical cell, the hematite photoanodes showed high activity to oxidize water, oxalate or phenol molecules, resulting in hydrogen generation on the counter electrode. This work shines a new light in the direction of environmental waste recycling. [ABSTRACT FROM AUTHOR]

A novel thermo- and biodegradable MnSt2-kaolin-polyethylene (signed as MKPE) composite film was prepared through a melt blending technique. Manganese stearate and common kaolin were employed as thermo-degradable additives and biodegradable promoter to improve the degradable efficiency of the waste PE. Thermo-oxidative testing was carried out in an air oven maintained at 70°C simulating a compost temperature. The biodegradation of the aging films was also investigated by analysis of evolved carbon dioxide of films in aquatic test systems according to the International Standards ISO 14852 (1999). The composite film was characterized by electronic universal testing machine, scanning electron microscopy, energy-dispersive X-ray spectroscopy, attenuated total reflection-flourier transformed infrared spectroscopy and thermo gravimetric analysis. These results showed that the MKPE film exhibited a high degree of susceptibility to thermo-oxidation and biodegradation. After thermal aging for 30 days, the mechanical properties of MKPE films reduced quickly and oxygen groups were introduced into the polymer chains. The kaolin particles wrapped in polymers were exposed gradually because of the rupture of polymer chains by thermal aging. The biodegradation degree reached 24.26% after incubation in an aqueous medium for 60 days. A possible mechanism for thermal oxidative degradation and biodegradation was also discussed. POLYM. COMPOS., 36:939-945, 2015. © 2014 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]