A mini-review on the development of Si-based thin film anodes for Li-ion batteries

This review provides a summary of the progress in research on various Si-based thin films as anode materials for lithium-ion batteries. The lithiation mechanism models, different types of materials from pure monolithic Si thin film to Si-based three-dimensional structured composite thin films, the effect of liquid and solid-state electrolytes on the performance of Si were considered and various available preparation techniques were discussed. A table summarizing important information on such systems including the thin film features, preparation methods and conditions, electrochemical test conditions and obtained results in order to elucidate the approaches used to prepare a stable thin film anode with high capacity and long cycle life is provided. We believe that this review will help the researchers to find some answers and induce some new ideas

Energy applications of ionic liquids

Ionic liquids offer a unique suite of properties that make them important candidates for a number of energy related applications. Cation–anion combinations that exhibit low volatility coupled with high electrochemical and thermal stability, as well as ionic conductivity, create the possibility of designing ideal electrolytes for batteries, super-capacitors, actuators, dye sensitised solar cells and thermoelectrochemical cells. In the field of water splitting to produce hydrogen they have been used to synthesize some of the best performing water oxidation catalysts and some members of the protic ionic liquid family co-catalyse an unusual, very high energy efficiency water oxidation process. As fuel cell electrolytes, the high proton conductivity of some of the protic ionic liquid family offers the potential of fuel cells operating in the optimum temperature region above 100 °C. Beyond electrochemical applications, the low vapour pressure of these liquids, along with their ability to offer tuneable functionality, also makes them ideal as CO2 absorbents for post-combustion CO2 capture. Similarly, the tuneable phase properties of the many members of this large family of salts are also allowing the creation of phase-change thermal energy storage materials having melting points tuned to the application. This perspective article provides an overview of these developing energy related applications of ionic liquids and offers some thoughts on the emerging challenges and opportunities