A review on the prominence of porosity in tungsten oxide thin films for electrochromism

Transition metal oxides have gained substantial attention in the previous decade by virtue of their distinctive physical and chemical properties. Amidst all, tungsten oxide (WO3) is emerging as distinct metal oxide on account of its outstanding electrochromic performance. Furthermore, optical-switching speed has topmost importance in the actual device. The sole approach to enhance this attribute is to escalate surface area of the electrochromic coatings, which can be done by instigating porosity within bulk material. Porosity can be considered as one of the pivotal facets of functionalized electrochromic thin films. Cations can be made to get transported into the depth of the host with the presence of high porosity in a structure. This featured article is attempting to pivot the path as how porosity is upgrading the electrochromic attribute of WO3 films. Furthermore, various methods to achieve optimum porosity of WO3 films leading to best electrochromic performance are also discussed.