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Pyrolysis is a promising approach for converting biomass to solids, liquids, and gases. Herein wood vinegars (WVs) were produced from pyrolysis of Eucommia ulmoides Olivers (EUO) branches in different temperature ranges that were labeled as WV90∼120 and WV480∼510. The yield, the physicochemical characteristics, the chemical composition, and the antimicrobial activity of the WVs were comprehensively investigated. During the pyrolysis process, as the temperature increased, the yield of the WVs increased firstly and then decreased, and WV300∼330 achieved the maximum yield of 236.79 g, accounting for 23.26% of the total amount of raw WVs. However, both the lowest pH value (2.39) and the highest total acid content (12.70%) occurred for WV270∼300. GC-MS results demonstrated that six components of WVs for WV300∼330 were phenols, ketones, aldehydes, alcohols, organic acids, and benzenes, while no clear regularity between the contents of each component and the reaction temperature was found. Thereafter, the antimicrobial activity of WVs was tested, and the results showed that the longest inhibition circle diameter of 24.50 mm for Enterobacter aerogenes was obtained for WV300∼330 indicating an excellent antibacterial activity; the overall inhibitory effects of WVs on bacteria were superior to those of plant pathogens and fungus. Therefore, WV300∼330 showed a better antimicrobial activity than that of WV270∼300 in this study. The result could be a reference for the further utilization of WVs in the field of antimicrobial development.

In the present report, hierarchical CuBi2O4 microspheres are prepared through a hydrothermal route, and applied as anode materials for LIBs. The hierarchical CuBi2O4 microspheres of diameter 2.0–4.0 μm are assembled by crystalline tetragonal nanoparticles with a size of 50–60 nm. The electrochemical performance of the hierarchical CuBi2O4 microspheres shows strong temperature-dependence whereby higher temperatures evidently enhance the electrochemical performance. At an elevated temperature of 70 °C, a reversible capacity of 525.1 mA h g−1 has been achieved after 500 cycles at a current density of 100 mA g−1. Even after being cycled at a high current density of 6.4 A g−1, the hierarchical CuBi2O4 microspheres are still able to deliver a capacity of 585 mA h g−1 when the current density is set back to 100 mA g−1. The superior high-temperature electrochemical performance of the hierarchical CuBi2O4 microspheres is ascribed to their hierarchical structure and outstanding thermostability.

A general approach for the synthesis of dibenzofulvene-based derivatives is demonstrated. The bisanthracene modified dibenzofulvene (F-DAn) exhibits efficient piezofluorochromic properties with the fluorescence reversibly altered between green (536 nm) and red (620 nm) under external stimuli.

In recent years low molecular weight carbazole-based materials have attracted much interest as hole-transporting and host materials for organic light emitting diode (OLED) applications. Herein we report the tri- and tetra-bromination of carbazole and the subsequent synthesis of novel carbazole oligomers substituted at the 1- and 8-positions. The oligomer series range from mono-carbazole (Cz-1) to quinque-carbazole (Cz-5) and we have carried out a comparative study of their thermal, optical, electrochemical and optoelectronic properties. The glass transition temperature increases as the carbazole core is enlarged (0 °C to 54 °C) and all oligomers exhibit excellent thermal stability with high thermal decomposition temperatures in the range of 442 °C to 494 °C. From optical data and Raman spectroscopy we observe negligible changes in the effective conjugation length as the number of peripheral carbazole units increases. However, the oxidation potential decreases as the number of carbazole units increase, in which Cz-5 exhibits the highest HOMO level (−5.19 eV) compared to other carbazole oligomers in the series. All carbazole materials emit deep blue photoluminescence ranging from 416 to 432 nm in the solid-state. Finally, electrophosphorescence was demonstrated from solution processable guest-host organic light- emitting diodes (OLEDs) fabricated using Cz(2–5) as the host materials with device configuration ITO/PEDOT/Cz1–5 : 10% Ir(mppy)3/TPBi/LiF/Al. The device efficiency decreases from Cz-3 to Cz-5. The best OLED device that incorporates Cz-3 as the host exhibits a turn-on voltage of 2.8 V, maximum brightness of 2310 cd m−2, maximum power efficiency of 33.6 lm W−1, maximum current efficiency 35.5 cd A−1 and EQE of 10.6%.