Scheme 1. Schematic illustration of a) the fabrication of hierarchical p-Co 3 O 4 /n-TiO 2 -HPs and b) the spatially sequential catalytic process of sulfur.

The capacity fluctuation phenomenon during cycling, which is closely related with solid electrolyte interphase and plays a key role for the design for advanced electrode, could be frequently observed in the titanium-based anode. However, the underlying reason for capacity fluctuation still remains unclear with rare related reports. Here, the origin of capacity fluctuation is verified with a long-life NaTiO anode. The reaction mechanism, structural evolution and reaction kinetics during the reported sodiation/desodiation processes were carefully investigated. The gradually enhanced diffusion controlled contribution resulted in the capacity increasing. And the capacity decay could be ascribed to the irreversible reaction of metallic titanium formation and the increasing potential polarization. It is worth noting that sodium ions seem to partially reduce NTO to metallic state, which is irreversible. The present study can provide more information for the design of advanced NaTiO anode.

As one of the most promising candidates for next-generation energy storage systems, lithium-sulfur (Li-S) batteries have gained wide attention owing to their ultrahigh theoretical energy density and low cost. Nevertheless, their road to commercial application is still full of thorns due to the inherent sluggish redox kinetics and severe polysulfides shuttle. Incorporating sulfur cathodes with adsorbents/catalysts has been proposed to be an effective strategy to address the foregoing challenges, whereas the complexity of sulfur cathodes resulting from the intricate design parameters greatly influences the corresponding energy density, which has been frequently ignored. In this review, the recent progress in design strategies of advanced sulfur cathodes is summarized and the significance of compatible regulation among sulfur active materials, tailored hosts, and elaborate cathode configuration is clarified, aiming to bridge the gap between fundamental research and practical application of Li-S batteries. The representative strategies classified by sulfur encapsulation, host architecture, and cathode configuration are first highlighted to illustrate their synergetic contribution to the electrochemical performance improvement. Feasible integration principles are also proposed to guide the practical design of advanced sulfur cathodes. Finally, prospects and future directions are provided to realize high energy density and long-life Li-S batteries.

Background: The bHLH (basic helix-loop-helix) transcription factor is one of the largest families of transcription factors in plants, containing a large number of members with diverse functions. Chinese jujube (Ziziphus jujuba Mill.) is the species with the highest economic value in the family Rhamnaceae. However, the characteristics of the bHLH family in the jujube genome are still unclear. Hence, ZjbHLHs were first searched at a genome-wide level, their expression levels under various conditions were investigated systematically, and their protein-protein interaction networks were predicted. Results: We identified 92 ZjbHLHs in the jujube genome, and these genes were classified into 16 classes according to bHLH domains. Ten ZjbHLHs with atypical bHLH domains were found. Seventy ZjbHLHs were mapped to but not evenly distributed on 12 pseudo-chromosomes. The domain sequences among ZjbHLHs were highly conserved, and their conserved residues were also identified. The tissue-specific expression of 37 ZjbHLH genes in jujube and wild jujube showed diverse patterns, revealing that these genes likely perform multiple functions. Many ZjbHLH genes were screened and found to be involved in flower and fruit development, especially in earlier developmental stages. A few genes responsive to phytoplasma invasion were also verified. Based on protein-protein interaction prediction and homology comparison, protein-protein interaction networks composed of 92 ZjbHLHs were also established. Conclusions: This study provides a comprehensive bioinformatics analysis of 92 identified ZjbHLH genes. We explored their expression patterns in various tissues, the flowering process, and fruit ripening and under phytoplasma stress. The protein-protein interaction networks of ZjbHLHs provide valuable clues toward further studies of their biological functions.

Fundamentally understanding the structureproperty relationship is critical to design advanced electrocatalysts for lithium-sulfur (LiÀ S) batteries, which remains a formidable challenge. Herein, by manipulating the regulable cations in spinel oxides, their geometrical-site-dependent catalytic activity for sulfur redox is investigated. Experimental and theoretical analyses validate that the modulation essence of cooperative catalysis of lithium polysulfides (LiPSs) is dominated by LiPSs adsorption competition between Co 3 + tetrahedral (Td) and Mn 3 + octahedral (Oh) sites on Mn 3 + Oh À OÀ Co 3 + Td backbones. Specifically, high-spin Co 3 + Td with stronger CoÀ S covalency anchors LiPSs persistently, while electron delocalized Mn 3 + Oh with adsorptive orbital (d z 2 ) functions better in catalyzing specialized LiPSs conversion. This work inaugurates a universal strategy for sculpting geometrical configuration to achieve charge, spin, and orbital topological regulation in electrocatalysts for LiÀ S batteries.

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Although single-atom catalysts (SACs) have been largely explored in lithium–sulfur (Li–S) batteries, the commonly reported nonpolar transition metal-N4 coordinations only demonstrate inferior adsorption and catalytic activity toward shuttled lithium polysulfides (LiPSs). Herein, single Fe atoms with asymmetric coordination configurations of Fe–N3C2–C were precisely designed and synthesized as efficient immobilizer and catalyst for LiPSs. The experimental and theoretical results elucidate that the asymmetrically coordinated Fe–N3C2–C moieties not only enhance the LiPSs anchoring capability by the formation of extra π-bonds originating from S p orbital and Fe d x 2–y 2 /d xy orbital hybridization but also boost the redox kinetics of LiPSs with reduced Li2S precipitation/decomposition barrier, leading to suppressed shuttle effect. Consequently, the Li–S batteries assembled with Fe–N3C2–C exhibit high areal capacity and cycling stability even under high sulfur loading and lean electrolyte conditions. This work highlights the important role of coordination symmetry of SACs for promoting the practical application of Li–S batteries.

Background Among several TF families unique to eukaryotes, the basic leucine zipper (bZIP) family is one of the most important. Chinese jujube ( Ziziphus jujuba Mill.) is a popular fruit tree species in Asia, and its fruits are rich in sugar, vitamin C and so on. Analysis of the bZIP gene family of jujube has not yet been reported. In this study, ZjbZIP s were identified firstly, their expression patterns were further studied in different tissues and in response to various abiotic and phytoplasma stresses, and their protein-protein interactions were also analyzed. Results At the whole genome level, 45 ZjbZIPs were identified and classified into 14 classes. The members of each class of bZIP subfamily contain a specific conserved domain in addition to the core bZIP conserved domain, which may be related to its biological function. Relative Synonymous Codon Usage (RSCU) analysis displayed low values of NTA and NCG codons in ZjbZIP s, which would be beneficial to increase the protein production and also indicated that ZjbZIP s were at a relative high methylation level. The paralogous and orthologous events occurred during the evolutionary process of ZjbZIPs . Thirty-four ZjbZIPs were mapped to but not evenly distributed among 10 pseudo- chromosomes. 30 of ZjbZIP genes showed diverse tissue-specific expression in jujube and wild jujube trees, indicating that these genes may have multiple functions. Some ZjbZIP genes were specifically analyzed and found to play important roles in the early stage of fruit development. Moreover, some ZjbZIP s that respond to phytoplasma invasion and abiotic stress environmental conditions, such as salt and low temperature, were found. Based on homology comparisons, prediction analysis and yeast two-hybrid, a protein interaction network including 42 ZjbZIPs was constructed. Conclusions The bioinformatics analyses of 45 ZjbZIPs were implemented systematically, and their expression profiles in jujube and wild jujube showed that many genes might play crucial roles during fruit ripening and in the response to phytoplasma and abiotic stresses. The protein interaction networks among ZjbZIPs could provide useful information for further functional studies.