The is a comprehensive review on the needs and potential storage technologies for electrical grid that is expected to integrate significant levels of renewables. This review offers details of the technologies, in terms of needs, status, challenges and future R&d directions.

/pdf/electrochemical-energy-storage-for-green-grid-22ttg0wpz1.pdf

Electrochemical Energy Storage for Green Grid

A novel and simple method for preparing highly photoactive nanocrystalline F--doped TiO2 photocatalyst with anatase and brookite phase was developed by hydrolysis of titanium tetraisopropoxide in a mixed NH4F−H2O solution. The prepared F--doped TiO2 powders were characterized by differential thermal analysis-thermogravimetry (DTA-TG), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV−vis absorption spectroscopy, photoluminescence spectra (PL), transmission electron microscopy (TEM), and BET surface areas. The photocatalytic activity was evaluated by the photocatalytic oxidation of acetone in air. The results showed that the crystallinity of anatase was improved upon F- doping. Moreover, fluoride ions not only suppressed the formation of brookite phase but also prevented phase transition of anatase to rutile. The F--doped TiO2 samples exhibited stronger absorption in the UV−visible range with a red shift in the band gap transition. The photocatalytic activity of F--doped TiO2 powders prep...

Effects of F- Doping on the Photocatalytic Activity and Microstructures of Nanocrystalline TiO2 Powders

The progress in the research and development of high temperature sodium batteries suggests that all-solid-state batteries with inorganic or polymer solid electrolytes are promising power sources for a wide range of applications due to their high thermal stability, reliability, long-cycle life and versatile geometries. The electrolytes play a fundamental role in terms of current (power) density, the time stability, and the safety of batteries and, as a result, their continuous improvement and innovation are indeed critical to success. In fact, inorganic solid electrolytes pave the way for improving the cost-effective development of rechargeable sodium batteries. This review describes a state-of-the-art overview of most of the Na+ conductors for use as electrolytes in sodium/sulphur and ZEBRA batteries. The emphasis of this article is on inorganic solid electrolytes, especially, ceramic and glass-ceramic electrolytes as promising alternatives applicable to all solid-state batteries. As part of a continuous effort to find new materials that operate at room temperature and moderate temperatures, NASICON electrolytes will also be considered. Polymer electrolytes based on poly(ethylene oxide) (PEO) are also very suitable for all solid-state batteries. Hence, the review focuses on ion transport based on the observed conductivity, electrolyte preparation, safety and environmental impact.

High temperature sodium batteries: status, challenges and future trends

Effects of acidic and basic hydrolysis catalysts on the photocatalytic activity and microstructures of bimodal mesoporous titania

Advanced materials for sodium-beta alumina batteries: Status, challenges and perspectives

TiO2 precursors were prepared by the sol-gel method using titanium tetraisopropoxide. The effects of water and hydrochloric acid addition for the hydrolysis and polymerization reaction on the crystal lattice or the molecular structure, and on the crystallization behaviour of prepared precursors, were examined by using Raman, and infrared spectroscopy, X-ray diffraction, DTA-TG and carbon analysis. The quantity of unhydrolysed alkyls in precursors decreased with increasing amounts of H2O and HCl addition, but the alkyls always remained. Raman spectroscopy revealed that the molecular structure of prepared amorphous precursors resembled that of the anatase phase with increased H2O and HCl addition. On the crystallization process of these precursors, the ratio of anatase formed at 310 °C was influenced by residual unhydrolysed alkyls. Steric hindrance by the residual alkyls preventing crystallization to crystalline anatase was observed, and there was estimated to be 2.5 mol of octahedral coordination of Ti-O per 1 mol of residual alkyls. It is noted that crystallization of the anatase phase and the transformation from anatase to the rutile phase were also observed on long-term ageing of precursors at room temperature.

Microstructure and crystallization behaviour of TiO2 precursor prepared by the sol-gel method using metal alkoxide

Ionic conduction in Sr hexa-aluminate with β-alumina structure

Formation and crystallization of beta-alumina from precursor prepared by sol-gel method using metal alkoxides

The high-temperature resistivity of YBa2Cu3O7-x was measured by a DC four-probe technique at partial oxygen pressures (pO2 ) of 1.0, 0.2, 0.053, 0.013 and 0.006 atm. The determined resistivity values increased with increasing temperature and decreasing pO2 in accordance with the increase of the oxygen deficiency. The discontinuous change of the slopes d(log ρ)/d(1/T) was observed at temperatures 20–95°C lower than those reported for the orthorhombic-to-tetragonal transition.

Atsuo Imai

Papers

Microstructure and crystallization behaviour of TiO2 precursor prepared by the sol-gel method using metal alkoxide

Ionic conduction in Sr hexa-aluminate with β-alumina structure

Formation and crystallization of beta-alumina from precursor prepared by sol-gel method using metal alkoxides

High-Temperature Resistivity Measurements of YBa2Cu3O7-x

Characterization of sodium β-alumina prepared by sol-gel method