Mingyu Ma

Abstract The bactericidal mechanism of plasma activated water (PAW) is an important issue that needs to be addressed in plasma medicine. In this paper, the pH value and the concentrations of RONS (H 2 O 2 , , , OH·, ONOOH and 1 O 2 ) in PAW were measured by chemical and optical methods. The bacteria E. coli was used as a microbial model to study the bactericidal effects of PAW. It was found that the concentration of peroxynitrous acid (ONOOH) in PAW was too low to directly realize complete bactericidal effects of PAW. Actually, ONOOH further interacted with H 2 O 2 to generate peroxynitric acid (O 2 NOOH), which eventually decomposed into superoxide anion radical ( ·) and singlet oxygen ( 1 O 2 ); these two species enhanced the bactericidal effects of PAW substantially.

Topology influences the properties and applications of polymers. Consequently, considerable efforts have been made to control topological structures. In this work, we have developed a photoorganocatalyzed divergent synthetic approach based on reversible-deactivation radical polymerization (RDRP) that enables the preparation of both linear and branched fluoropolymers of low dispersity (Ð), a tunable degree of branching and high chain-end fidelity by exposure to LED light irradiation under metal-free conditions. This method promotes the generation of complicated structures (e.g., necklace-like and mop-like fluoropolymers) via chain-extension photo-RDRP, and provides a novel and versatile platform to access fluoropolymer electrolytes with high Li-ion transference number and good ionic conductivity, which should create improved opportunities for advanced material engineering.

Polymer networks cross-linked by dynamic covalent bonds possess outstanding mechanical and rheological properties and are expected to be potential alternatives to conventional thermosets. However, while many recent studies of dynamically cross-linked thermosets focused on the employment of small molecular cross-linkers, the macro-cross-linking approach and the corresponding thermosets have been less demonstrated. In this work, reconfigurable and catalyst-free thermosets were synthesized by dynamic polymer–polymer interaction based on reversible boronic ester bond, providing simple and efficient access toward materials with improved mechanical strength and toughness in comparison to related commodity thermoplastics. The dynamic exchange of covalent bonds dispersed between polymer chains enables the materials to be malleable, recyclable, and healable under thermal conditions and readily processable with mechanical mixing without solvent. Moreover, the materials’ mechanical and rheological properties could be tuned by changing the cross-linking density. Although the dynamic networks exhibited good resistance against organic solvents, they could be cleaved as triggered by acids or diols and recycled through the de-cross-linking/re-cross-linking pathway. Given the dramatically increasing interest in environmentally sustainable materials, this polymer–polymer interaction mode provides a robust approach to engineering polymers with improved performance compared with the thermoplastic counterparts.

In this work, high voltage and high performance 3 V asymmetric supercapacitors were obtained by combining a VN nanowire electrode with an ultra-high concentration “water in salt” electrolyte.