Ion beam engineering of nanostructured materials for superior performance in supercapacitor applications: Recent progress and future perspectives

In recent times, efforts were made by researchers worldwide, to enhance the performance of energy storage devices such as innovative modification and synthesis of different low dimensional nanomaterials, and optimisation of electrode materials in order to achieve an optimised power and energy density with increased lifetime. The ion-irradiation technique has been recognised as a promising technology among several other methodologies that can change materials in desirable manners. Ion beam technique has the ability to achieve arbitrary elemental doping without caring about ionic radius mismatch and it does not introduce any undesired contaminants into the target materials during the treatment process. Ion beam can further control defects and structural properties, which may act in favour of desired technology such as charge storage. In this review, the effect of ion beam irradiation on various electrode materials is discussed in detail. The effects include the introduction of defects, the regulation of the electronic structure, morphological control, and enhancing the electrical conductivity among other modifications. The use of ion-irradiated electrode materials in energy storage devices (mainly supercapacitors) are then summarised, with a focus on the benefits of increasing the characteristics of the materials and the performance of the final device. In conclusion, the challenges that need to be overcome and potential solutions are discussed in order to make ion irradiation techniques more applicable to the production of high-performance electrode materials for energy storage applications.