Ionogels combine the virtues of polymers and ionic liquids (ILs) and have greater potential for supercapacitors (SCs) than hydrogels and organic gels. Undoubtedly, the self-healing ability of ionogels dramatically improves the reliability of related SCs. Herein, we reported a dynamic diol-borate ester-cross-linked polyvinyl alcohol (PVA) ionogel electrolyte for smart double-layer capacitors. The results indicated that 1-ethyl-3-methylimidazolium chloride (EmimCl) could form a strong interaction with the hydroxy groups on PVA, thereby depressing the crystallization efficiently. The resultant ionogel exhibited an amorphous nature with excellent ionic conductivity up to 2.43 × 10–3 S/cm, high flexibility, and 95% healing efficiency when the IL content was 90 vol %. It could be inferred from the fact that EmimCl acted not only as an ion provider to improve the ionic conductivity but also as a plasticizer to enhance the chain mobility and self-healing efficiency. Based on the unique properties of PVA-boric acid/EmimCl ionogels, a flexible and self-healable SC was assembled. The as-prepared SC delivered a specific capacitance of 90 F/g at 0.1 A/g and retained 98% capacitance after 3000 charge–discharge cycles at a current density of 2 A/g. More interestingly, it could tolerate physical bending and healing without significant performance deterioration. The present study provides a novel strategy to prepare self-healable ionogel electrolytes that can be applied to smart energy storage devices.

The schematic diagram of preparing the composite scaffolds.

Based on genetic diversity analysis with ISSR-PCR, this study was to access the germplasm resources of Platycodon grandiflorum in northern Anhui province. Ten primers that could produce more distinct and repeatable bands were used for ISSR-PCR. Statistic analysis was conducted by POPGENE v. 1.32, Arlequin3.l, NTSYS-pc version 2.1. (1) Seventy-four polymorphic bands (76.29 %) out of a total of 97 were generated from 105 individuals in five populations. (2) Shannon index of diversity ranged from 0.307 to 0.260, diversity at species level was 0.3581, which means superior genetic diversity. (3) Genetic diversity across all the populations revealed by AMOVA indicated that 86.02 % occurred within populations. (4) The Fst value was 0.1398, indicating a intermediate genetic differentiation among populations. (5) Dendrogram relationship illustrated genetic distance was correlated with geographic distance. ISSR markers can be used for studying genetic diversity of P. grandiflorum. Degradation of populations doesn't happen in northern Anhui province, bank of germplasm preservation should be established for cultivation of excellent variety of P. grandiflorum.