Flexible Aqueous Cr-Ion Hybrid Supercapacitors with Remarkable Electrochemical Properties in all Climates.

The integration of hostless battery-like metal anodes for hybrid supercapacitors is a realistic design method for energy storage devices with promising future applications. With significant Cr element deposits on Earth, exceptionally high theoretical capacity (1546 mAh g-1), and accessible redox potential (-0.74 V vs. reversible hydrogen electrode) of Cr metals, the design of Cr anodes has rightly come into our focus. This work presents a breakthrough design of a flexible Cr-ion hybrid supercapacitor (CHSC) based on a porous graphitized carbon fabric (PGCF) substrate prepared by K2FeO4 activation. In the CHSC device, PGCF acts as both a current collector and cathode material due to its high specific surface area and superior conductivity. The use of a highly concentrated LiCl-CrCl3 electrolyte with high Cr plating/stripping efficiency and excellent antifreeze properties enables the entire PGCF-based CHSC to achieve well-balanced performance in terms of energy density (up to 1.47 mWh cm-2), power characteristics (reaching 9.95 mW cm-2) and durability (95.4 % capacity retention after 30,000 cycles), while realizing it to work well under harsh conditions of -40 °C. This work introduces a new concept for low-temperature energy storage technology and confirms the potential application of Cr anodes in hybrid supercapacitors.

Urchin-like (NH4)2V10O25·8H2O hierarchical arrays with significantly expanded interlayer spacing for superior aqueous zinc-ion batteries.

The practical application of zinc ion batteries (ZIBs) can be facilitated by designing cathode materials with unique structures that can overcome the critical problems of slow reaction kinetics and large volume expansion associated with the intercalation reaction of divalent zinc ions. In this study, a novel urchin-like (NH4)2V10O25·8H2O assembled from nanorods was synthesized by a simple hydrothermal method, noted as U-NVO. The interlayer organic pillar of cetyltrimethylammonium cation (CTAB) has been intercalated between layers to regulate the interlayer microstructure and expand the interlayer spacing to 1.32 nm, which effectively increased the contact between the electrode and electrolyte interface and shortened the diffusion path of electrolyte ions. The interlayer pillars of structural H2O and NH4+ provide a flexible framework structure and enhance the cohesion of the layered structure, which helps to maintain structural stability during the charging and discharging process, resulting in long-term durability. These unique properties result in the U-NVO cathodes demonstrating high specific capacity (401.7 mA h g-1 at 0.1 A g-1), excellent rate capability (99.6 % retention from 0.1 to 5 A g-1 and back to 0.1 A g-1), and long-term cycling performance (∼87.5 % capacity retention after 2600 cycles). These results offer valuable insights into the design of high-performance vanadium oxide cathode materials.

The MYB transcription factor OsMYBxoc1 regulates resistance to Xoc by directly repressing transcription of the iron transport gene OsNRAMP5 in rice.

Bacterial leaf streak caused by Xanthomonas oryzae pv. oryzicola (Xoc) is a continuous threat to rice cultivation, leading to substantial yield losses with socioeconomic implications. Iron ions are essential mineral nutrients for plant growth, but little information is available on how they influence mechanisms of rice immunity against Xoc. Here, we investigated the role of the myeloblastosis-related (MYB) transcriptional repressor OsMYBxoc1 in modulation of rice resistance through control of iron ion transport. Overexpression of OsMYBxoc1 significantly increased rice resistance, whereas OsMYBxoc1 RNA-interference lines and knockout mutants showed the opposite result. Suppression of OsMYBxoc1 expression dampened the immune response induced by pathogen-associated molecular patterns. We demonstrated that OsMYBxoc1 binds specifically to the OsNRAMP5 promoter and represses transcription of OsNRAMP5. OsNRAMP5, a negative regulator of rice resistance to bacterial leaf streak, possesses metal ion transport activity, and inhibition of OsMYBxoc1 expression increased the iron ion content in rice. Activity of the ion-dependent H2O2 scavenging enzyme catalase was increased in plants with suppressed expression of OsMYBxoc1 or overexpression of OsNRAMP5. We found that iron ions promoted Xoc infection and interfered with the production of reactive oxygen species induced by Xoc. The type III effector XopAK directly inhibited OsMYBxoc1 transcription, indicating that the pathogen may promote its own proliferation by relieving restriction of iron ion transport in plants. In addition, iron complemented the pathogenicity defects of the RS105_ΔXopAK mutant strain, further confirming that iron utilization by Xoc may be dependent upon XopAK. In conclusion, our study reveals a novel mechanism by which OsMYBxoc1 modulates rice resistance by regulating iron accumulation and demonstrates that Xoc can accumulate iron ions by secreting the effector XopAK to promote its own infection.