In situ crystallization of high performing WO3-based electrochromic materials and the importance for durability and switching kinetics

Electrochromism in sputter-deposited W–Ti oxide films: Durability enhancement due to Ti

“…The Ti was found to promote stability both for crystallization at elevated temperature and for the electrochromic performance under extended cycling in a Li-conducting electrolyte. Our data are consistent with those in prior work [14][15][16][17][18]26,30] as regards crystallization and support earlier evidence concerning the ability of Ti to prevent permanent incorporation of Li. Furthermore, our data indicate that low sputtering powers are connected with improved stability under electrochemical cycling.…”

“…This effect is also advantageous with regard to EC performance [26] since as-sputtered films-prepared at low substrate temperature and high sputter gas pressure as in the present work-have a nanostructure with pores extending across the film thickness [32].…”

“…The enhanced stability has been investigated in depth in recent work on W-Ti oxide films made by sputtering [30,31] and chemical techniques [26]. Data based on electrochemical measurements, transmission electron microscopy, atomic force microscopy and Raman spectroscopy verify [26,30] that the Ti addition makes the crystallization occur at a higher temperature than in a film of pure W oxide.…”

“…Other, supporting studies on the electrochromism in W-Ti oxide have been reported for films prepared by sputtering [16][17][18][19], chemical technology involving spraying [20][21][22] dipping [16,23] or spinning [24][25][26], electrodeposition [27,28] and anodization [29]. The enhanced stability has been investigated in depth in recent work on W-Ti oxide films made by sputtering [30,31] and chemical techniques [26]. Data based on electrochemical measurements, transmission electron microscopy, atomic force microscopy and Raman spectroscopy verify [26,30] that the Ti addition makes the crystallization occur at a higher temperature than in a film of pure W oxide.…”

Electrochromic Composite Films of Tunable Color based on Polyoxometalate and Auxiliary Materials

“…Electrochromic materials that change their optical properties during electrochemical oxidation and reduction have displayed great potential for applications such as smart windows, antiglare mirrors and displays [1,2]. Recently, much effort has been dedicated to the improvement of the electrochromic properties including optical contrast, coloration efficiency and multicolor.…”