Jun Zang

A novel bi-functional double-layer rGO–PVDF/PVDF composite nanofiber membrane separator with enhanced thermal stability and effective polysulfide inhibition for high-performance lithium–sulfur batteries

A novel, bi-functional double-layer reduced graphene oxide (rGO)–polyvinylidene fluoride (PVDF)/PVDF membrane was fabricated by a simple electrospinning technique and was used as a promising separator for lithium–sulfur batteries. This double-layer membrane separator delivers two different functionalities: (i) the porous PVDF nanofiber framework in both rGO–PVDF and PVDF layers provides good thermal stability and maintains the structural integrity of the separator; and (ii) the conductive rGO–PVDF layer serves as a polysulfide inhibitor and ensures the fast transfer of lithium ions. Compared to conventional polypropylene membrane separators, this new separator design can significantly enhance the cycling stability and rate capability of the incorporated lithium–sulfur batteries. Overall, it is demonstrated that this new double-layer rGO–PVDF/PVDF composite membrane separator opens an alternate avenue in the structural design of high-performance lithium–sulfur batteries in dealing with multiple challenges.

Sol-Gel Synthesis of Carbon Xerogel-ZnO Composite for Detection of Catechol

Carbon xerogel-zinc oxide (CXZnO) composites were synthesized by a simple method of sol-gel condensation polymerization of formaldehyde and resorcinol solution containing zinc salt followed by drying and thermal treatment. ZnO nanoparticles were observed to be evenly dispersed on the surfaces of the carbon xerogel microspheres. The as-prepared CXZnO composites were mixed with laccase (Lac) and Nafion to obtain a mixture solution, which was further modified on an electrode surface to construct a novel biosensing platform. Finally, the prepared electrochemical biosensor was employed to detect the environmental pollutant, catechol. The analysis result was satisfactory, the sensor showed excellent electrocatalysis towards catechol with high sensitivity (31.2 µA·mM−1), a low detection limit (2.17 µM), and a wide linear range (6.91–453 µM). Moreover, the biosensor also displayed favorable repeatability, reproducibility, selectivity, and stability besides being successfully used in the trace detection of catechol existing in lake water environments.

Li0.33La0.557TiO3 ceramic nanofiber-enhanced polyethylene oxide-based composite polymer electrolytes for all-solid-state lithium batteries

A polyethylene oxide (PEO)-based composite solid polymer electrolyte filled with one-dimensional (1D) ceramic Li0.33La0.557TiO3 (LLTO) nanofibers was designed and prepared. It exhibits a high ionic conductivity of 2.4 × 10−4 S cm−1 at room temperature and a large electrochemical stability window of up to 5.0 V vs. Li/Li+, and is a promising electrolyte candidate for all solid-state lithium batteries.