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Iron-based Prussian blue analogs are promising low-cost and easily prepared cathode materials for sodium-ion batteries. Their materials quality and electrochemical performance are heavily reliant on the precipitation process. Here we report a controllable precipitation method to synthesize high-performance Prussian blue for sodium-ion storage. Characterization of the nucleation and evolution processes of the highly crystalline Prussian blue microcubes reveals a rhombohedral structure that exhibits high initial Coulombic efficiency, excellent rate performance, and cycling properties. The phase transitions in the as-obtained material are investigated by synchrotron in situ powder X-ray diffraction, which shows highly reversible structural transformations between rhombohedral, cubic, and tetragonal structures upon sodium-ion (de)intercalations. Moreover, the Prussian blue material from a large-scale synthesis process shows stable cycling performance in a pouch full cell over 1000 times. We believe that this work could pave the way for the real application of Prussian blue materials in sodium-ion batteries.

Background:The molecular mechanism underlying the regulation of cellulase production by T. reesei is unclear. Results: The absence of sugar transporter Stp1 enhanced cellulase gene induction whereas the absence of Crt1 abolished cellulase gene expression. Conclusion: Crt1 is essential in cellulase gene induction independent of intracellular sugar delivery. Significance: These data shed light on the mechanism by which T. reesei senses and transmits cellulose signal.

In this paper, we report the growth of ultrathin Ni(OH) 2 nanosheets on nickel foam at room temperature via a cost-effective and simple process, oxidizing fresh nickel foam in a wet environment followed by a morphology transformation in a mixed alkaline and oxidative solution without the need for any additional nickel sources, templates, or surfactant. When tested as electrode for a supercapacitor, the Ni(OH) 2 nanosheets grown on nickel foam displayed excellent performance, demonstrating specific capacitance of 2384.3 F g-1 at a charge and discharge current density of 1 A g-1 and 1288.1 F g-1 at 5 A g-1 with a good cycling ability (~75% of the initial specific capacitance remained after 3000 cycles). The excellent electrochemical performance is attributed to its unique nanostructures, which may facilitate rapid ion transport near electrode surfaces, while allowing facile redox reactions associated with charge storage by the nanosheets. The demonstrated high specific capacity and the remarkable rate performance of the Ni(OH) 2 nanosheets, together with the flexibility of the nickel foam substrate, make the three-dimensional nanostructured electrodes ideally suited for low-cost, high-performance supercapacitor applications.

This review provides insight into various nanostructures designed by spray pyrolysis and their applications in energy storage and conversion.