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GATA transcription factors have been reported to function in plant growth and development and during various biotic/abiotic stresses in Arabidopsis and rice. However, the functions of wheat GATAs, particularly in the regulation of seed dormancy and germination, remain unclear. Here, we identified 78 TaGATAs in wheat and divided them into five subfamilies. Sixty-four paralogous pairs and 52 orthologous pairs were obtained, and Ka/Ks ratios showed that the TaGATAs had undergone strong purifying election during the evolutionary process. Triplet analysis indicated that a high homologue retention rate could explain the large number of TaGATAs in wheat. Gene structure analysis revealed that most members of the same subfamily had similar structures, and subcellular localization prediction indicated that most TaGATAs were located in the nucleus. Gene ontology annotation results showed that most TaGATAs had molecular functions in DNA and zinc binding, and promoter analysis suggested that they may play important roles in growth, development, and biotic/abiotic stress response. We combined three microarray datasets with qRT-PCR expression data from wheat varieties of contrasting dormancy and pre-harvest sprouting resistance levels during imbibition in order to identify ten candidate genes (TaGATA17/-25/-34/-37/-40/-46/-48/-51/-72/-73) that may be involved in the regulation of seed dormancy and germination in wheat. These findings provide valuable information for further dissection of TaGATA functions in the regulation of seed dormancy and germination, thereby enabling the improvement of wheat pre-harvest sprouting resistance by gene pyramiding.

Cubic phase garnet-type Li7La3Zr2O12 (LLZO) is a promising solid electrolyte for highly safe Li-ion batteries. Al-doped LLZO (Al-LLZO) has been widely studied due to the low cost of Al2O3. The reported ionic conductivities were variable due to the complicated Al3+-Li+ substitution and LixAlOy segregation in Al-LLZO ceramics. This work prepared Li7−3xAlxLa3Zr2O12 (x = 0.00~0.40) ceramics via a conventional solid-state reaction method. The AC impedance and corresponding distribution of relaxation times (DRT) were analyzed combined with phase transformation, cross-sectional microstructure evolution, and grain boundary element mapping results for these Al-LLZO ceramics to understand the various ionic transportation levels in LLZO with different Al-doping amounts. The low conductivity in low Al-doped (0.12~0.28) LLZO originates from the slow Li+ ion migration (1.4~0.25 μs) in the cubic-tetragonal mixed phase. On the other hand, LiAlO2 and LaAlO3 segregation occur at the grain boundaries of high Al-doped (0.40) LLZO, resulting in a gradual Li+ ion jump (6.5 μs) over grain boundaries and low ionic conductivity. The Li6.04Al0.32La3Zr2O12 ceramic delivers the optimum Li+ ion conductivity of 1.7 × 10−4 S cm−1 at 25 °C.

The unsatisfactory rate capability and poor cycling stability at high rate of sodium-ion batteries (SIBs) have impeded their practical applications. Herein, a Na3V2(PO4)3/Na3V3(PO4)4 multiphase cathode materials for high-rate and long cycling SIBs was successfully synthesized by regulation the stoichiometric ratio of raw materials. The combined experiment and simulation results show that the multiphase materials consisted of NASICON structural phase Na3V2(PO4)3 and layered structure phase Na3V3(PO4)4, possess abundant phase boundaries. Electrochemical experiments demonstrate that the multiphase materials maintain a remarkable reversible capacity of 69.0 mA h g−1 even at an ultrahigh current density of 100 C with a high capacity retention of 81.25 % even after 10,000 cycles. Na3V2(PO4)3/Na3V3(PO4)4 electrode exhibits a higher working voltage, superior rate capability and better cycling stability than Na3V2(PO4)3 electrode, which indicates that the introduction of second phase can be an effective strategy for the development of novel cathode materials for SIBs.

Poly(ethylene oxide) (PEO)-based polymer electrolytes are promising candidates for solid-state electrolytes in safer, next generation lithium metal batteries. Despite their benefits however, PEO-based electrolyte exhibits highly crystalline ethylene oxide chains that provide poor ionic conductivity and, thus severely limit its practical application. Here, we report the use of hydroxypropyl trimethylammonium bis(trifluoromethane) sulfonimide chitosan salt (HACC-TFSI), which is an amorphous poly(ionic liquid) based biomass chitosan derivative, as a modifier for PEO-based solid polymer electrolytes (SPEs) to address these deficiencies. Hybrid SPEs with HACC-TFSI display enlarged amorphous regions with enhanced ionic conductivity. Interactions between quaternary ammonium cations and TFSI− anions in hybrid SPEs are also found to promote dissociation between Li+ and TFSI−, which further increases ionic mobility. Moreover, the electrochemical stability, mechanical strength, and thermal stability of hybrid SPEs are collectively superior to blank SPEs without HACC-TFSI. LiFePO4/SPEs/Li full-cells assembled using 10wt% HACC-TFSI in PEO (10%HACC-TFSI/SPEs) electrolyte provide a capacity of 161.3 mAh g−1 and operate with excellent cycle performances at 0.2 C and 60 °C. Even when the temperature is increased to 150 °C, LiFePO4/SPEs/Li cells with 10%HACC-TFSI/SPEs still display remarkable cycle performance with 73% capacity retention after 100 cycles at 1 C rate.

The development of facile, inexpensive and large-scale methods to prepare carbon scaffolds with high sulfur content is crucial to the practical applications of Li-S Battery. Herein, Nitrogen, Oxygen and Cobalt multiple-doped graphitized mesoporous carbon sulfur composites (N-O-Co-C/S) with high sulfur content (90%) are developed via inexpensive carbonization methods. The composites exhibit superior performance with a capacity of 610 mAh g−1 at a current of 0.5 C after 200 cycles and 302 mAh g−1 at a current of 2 C after 1400 cycles. The superior performance of N-O-Co-C/S composites can be attributed to the enhanced electrical conductivity and ionic conductivity of Co-N-O-C/S composites, which can be supported by electrochemical impedance spectroscopy measurement. The polysulfide-trapping was mainly attributed to the strong O-S, N-S and Co-S interactions, thus improving the e electrochemical performance.

Solid polymer electrolytes (SPEs) are promising candidates for all-solid-state lithium batteries (ASSLBs) due to their advantages of good interfacial adhesion and shape flexibility. However, the low ionic conductivity at room temperature (RT) and inferior electrochemical stability at high voltages limit the practical applications of SPEs. In this work, we demonstrate a cryogenic engineering to improve PEO-based SPEs for ASSLBs operated at RT. The rapid in situ cooling process will lead to the uniform formation of PEO crystal nuclei, which can limit the PEO crystal growth in SPEs. The novel crystallization structure could promote the ionic conductivity of SPEs effectively. Such improved cryogenic SPEs display a superior ionic conductivity of 2.17 × 10−5 S cm−1 and a superior electrochemical stability at RT. A discharge capacity of 154.9 mAh g−1 can be achieved at 0.1 C and RT when LiFePO4 (LFP) is used as the cathode. The discharge capacity can remain at ~98%, even after 100 cycles performed at 0.1 C. Notably, cryogenic SPEs can be utilized in 4 V-class ASSLBs. A high discharge capacity of 118 mAh g−1 can be achieved at 0.2 C and RT with the LiNi0.6Co0.2Mn0.2O2 (NCM622) as the cathode and can retain a 94.1% capacity even after 100 cycles. These extraordinary performances of cryogenic SPEs break new ground for the fabrication of ASSLBs operated at RT and high voltages.

The performance of metal-free oxygen reduction reaction (ORR) electrocatalysts are far from satisfactory, thus impeding their real world application. Herein, we present a C3N4 self-templating method to construct a P and N co-doped porous carbon nanosheets with high ORR performance. The conbination of the templating effect and the synergy effect direved from N, P co-doping is revealed of utmost importance towards ORR. The optimized catalyst represents an outstanding ORR performance with an onset potential of 0.93 V and half-wave potential of 0.85 V, comparable to those of commercial Pt/C electrocatalysts (1.04 V, 0.84 V).

Solid polymer electrolytes (SPEs) have attracted considerable research interest because they are expected to solve the safety problems caused by the liquid electrolytes. However, the low ionic conductivity limits their practical applications. Constructing Li+ fast conducting network in SPEs with Li+ highly conducting ceramic fillers following the mixed matrix membrane concept have shown their limits in raising the Li+ conductivity. Herein, a new strategy using Li+ non-conducting fillers like CeO2 nanowires, is proposed to construct a Li+ fast conducting network through SPEs. CeO2 nanowires can dissociate LiTFSI, which results in a high Li+ conductivity through the SPEs near to the fiber surface. This experimental finding is confirmed by analytics (FT-IR, Raman and NMR) and theoretical calculations (DFT-MD and COHP). As a result, the network of interwoven CeO2 nanowires helps form a continuous Li+ fast conducting percolation network through the SPEs. The ionic conductivity of the composite SPEs with 10 wt% CeO2 nanowires is greatly improved (1.1 × 10−3 S cm−1 at 60 °C). The Li symmetric cells with this composite electrolyte exhibit good cyclic stability (without short circuiting after 2000 h), and the all-solid-state LiFePO4/Li cells present a superior cycling performance (remained 140 mA h g−1 after 100 cycles at 1 C).

This study focused on the investigation in the influencing factors of the Granick’s method for Janus particle synthesis, in which selective modification of colloidosome made from a Pickering emulsion-based process was the essential strategy. Homogenizer with high shearing forces was introduced to make stable emulsion. With increased stirring speed of the homogenizer, the sizes of the colloidosomes decrease. And the stirring time of the homogenizer and the paraffin melting point have also been proved to have influence on the size distribution of colloidosomes as well as on the assembly morphology of the silica particles on the surface of the wax sphere. 160 s of the working time and the melting point of 53−57 °C were tested respectively to be the optimal condition for making the ideal colloidosomes. By using the optimized experimental conditions, silica particles with diameters of 200, 400, and 600 nm all had success in making fine colloidosomes. The Janus character were characterized by demonstrating the abilities of interfacial assembly and anisotropic structural growth of the resultant products from the optimized procedure. The research provides the conclusions of optimal experimental conditions as references for achieving scalable synthesis of Janus particles with satisfactory quality. This research could serve as a guidance to effective implementation of Granick’s method of Janus particle synthesis.

Carbon materials are among the most important materials used for anodes in rechargeable batteries due to their extensive resources and good cycling stability. However, the electrochemical performance of carbon-based anodes is closely related with their electronic states and morphologies/microstructures. Herein, we present a simple approach to synthesize a nitrogen-doped 3D nanocarbon (N-Carbon) with nanopore defects as high-capacity and stable anodes for sodium/lithium-ion batteries. This carbon material well inherits the unique nanosheet-like morphology of the template, which is composed of twisted-interconnected cuboidal hollow nanocages with a large number of nanopores across the shells. N-Carbon with integration of N heteroatom and 3D porous structure exhibits high reversible capacities of sodium-ion batteries, up to 401.9 and 311.7 mAh g−1 at 0.1 and 0.5 A g−1 after 100 cycles, respectively. This unique carbon material simultaneously exhibits excellent rate capability and cycling stability, with reversible capacities of 199.7 and 97.9 mAh g−1 at large current densities of 1 and 5 A g−1 even after 10,000 cycles, respectively. Moreover, N-Carbon also exhibits high capacity of 709 mAh g−1 for lithium-ion batteries after 2500 cycles at 10 A g−1. The excellent reversibility, rate capability, and cycling stability are attributed to this unique N-Carbon integrating into rich nitrogen-doped induced ion-storage sites and its relative ordered 3D pore structure.

(Fe,Cr)-binary oxide thin film electrodes were prepared as negative electrode material for lithium-ion micro-batteries by thermal growth on a stainless steel (AISI 410, FeCr 12.5 ) current collector. The mechanisms of lithiation/delithiation were investigated by means of electrochemical (CV, galvanostatic cycling), spectroscopic (XPS, ToF-SIMS) and microscopic (SEM, AFM) analytical techniques. The as-prepared (Fe, Cr)-binary oxide electrodes exhibit a good cycling performance except the first discharge/charge cycle where a high irreversible capacity is observed due to formation of a solid electrolyte interphase (SEI) layer. The influence of substituting an oxidized iron by an oxidized chromium (Cr x Fe 2− x O 3 phase) was evaluated. The data show that the inferior electrochemical conversion activity of substituted oxidized chromium results in hindering lithium transport in the bulk thin film electrode. It was observed that the irreversible morphology modifications together with SEI evolution are critical to capacity degradation while retaining good coulombic efficiency.

Li4Ti5O12/graphene composite was prepared by a facile sol–gel method. The lattice structure and morphology of the composite were investigated by X-ray diffraction (XRD) and scanning electronic microscopy (SEM). The electrochemical performances of the electrodes have been investigated compared with the pristine Li4Ti5O12 synthesized by a similar route. The Li4Ti5O12/graphene composite presents a higher capacity and better cycling performance than Li4Ti5O12 at the cutoff of 2.5–1.0 V, especially at high current rate. The excellent electrochemical performance of Li4Ti5O12/graphene electrode could be attributed to the improvement of electronic conductivity from the graphene sheets. When discharged to 0 V, the Li4Ti5O12/graphene composite exhibited a quite high capacity over 274 mAh g−1 below 1.0 V, which was quite beneficial for not only the high energy density but also the safety characteristic of lithium-ion batteries.

Niobium doped lithium titanate with the composition of Li4Ti4.95Nb0.05O12 has been prepared by a sol–gel method. X-ray diffraction (XRD) and scanning electron microscope (SEM) are employed to characterize the structure and morphology of Li4Ti4.95Nb0.05O12. The Li4Ti4.95Nb0.05O12 electrode presents a higher specific capacity and better cycling performance than the Li4Ti5O12 electrode prepared by the similar process. The Li4Ti4.95Nb0.05O12 exhibits an excellent rate capability with a reversible capacity of 135 mAh g−1 at 10 C, 127 mAh g−1 at 20 C and even 80 mAh g−1 at 40 C. Electrical resistance measurement and electrochemical impedance spectra (EIS) reveal that the Li4Ti4.95Nb0.05O12 exhibits a higher electronic conductivity and faster lithium-ion diffusivity than the Li4Ti5O12, which indicates that niobium doped lithium titanate (Li4Ti4.95Nb0.05O12) is promising as a high rate anode for the lithium-ion batteries.