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Rational design of novel structures plays a key role in achieving high specific capacities and fast charge rates with a long cycling life for battery-type electrodes of supercapacitors. To tackle capacity fading issues of battery-type electrode materials for supercapacitors, a new approach is proposed to form a bioinspired sea-sponge nanostructure of Ni/Ni(HCO3)2-on-C, synthesized through modifying triangle nanoflakes of Ni(HCO3)2 with partially in situ reduced Ni generated on sea-sponge-like porous carbon spheres (S-PCSs). The conductive skeleton of S-PCSs facilitates fast electron transfer and ion diffusion, and maintains the morphology of Ni(HCO3)2 triangle nanoflakes to ensure a high specific capacity of Ni/Ni(HCO3)2 nanoflakes. Simultaneously, the in situ reduced Ni acts as a capacity reservoir to prevent the fading of the specific capacity. When, applied as a positive electrode material, such sea-sponge nanostructures of Ni/Ni(HCO3)2-on-C exhibit a high specific capacity (472 mA h g−1) with a good rate capability (66% capacity retention at 32 A g−1vs. 8 A g−1), superior reversibility and cyclability (92% capacity retention after 10 000 cycles). An asymmetric supercapacitor based on Ni/Ni(HCO3)2-on-C//S-PCSs shows a high energy density of 51.3 W h kg−1 at a power density of 4 kW kg−1 with a capacitance retention of 89.6% over 6000 cycles. [ABSTRACT FROM AUTHOR]

Dipelta Maxim. (Caprifoliaceae) is a Tertiary relic genus endemic to China, which includes three extant species, Dipelta floribunda, Dipelta yunnanensis, and Dipelta elegans. Recent progress in the systematics and phylogeographics of Dipelta has greatly broadened our knowledge about its origin and evolution, however, conflicted phylogenetic relationships and divergence times have been reported and warrant further investigation. Here, we utilized chloroplast genomes and population‐level genomic data restriction site‐associated DNA‐single nucleotide polymorphisms (RAD‐SNPs) to evaluate the interspecific relationships, population genetic structure and demographic histories of this genus. Our results confirmed the sister relationship between D. elegans and the D. yunnanensis–D. floribunda group, but with cyto‐nuclear phylogenetic discordance observed in the latter. Coalescent simulations suggested that this discordance might be attributed to asymmetric “chloroplast capture” through introgressive hybridization between the two parapatric species. Our fossil‐calibrated plastid chronogram of Dipsacales and the coalescent modeling based on nuclear RAD‐SNPs simultaneously suggested that the three species of Dipelta diversified at the late Miocene, which may be related to the uplift of the eastern part of Qinghai–Tibet Plateau (QTP) and adjacent southwest China, and increasing Asian interior aridification since the late Miocene; while in the mid‐Pleistocene, the climatic transition and continuous uplift of the QTP, triggered allopatric speciation via geographical isolation for D. floribunda and D. yunnanensis regardless of bidirectional gene flow. Based on both plastid and nuclear genome‐scale data, our findings provide the most comprehensive and reliable phylogeny and evolutionary histories for Dipelta and enable further understanding of the origin and evolution of floristic endemisms of China. [ABSTRACT FROM AUTHOR]