Performance device electrochromic

PENNARUN, P.Y., JANNASCH, p., PAPAEFTHiMiou, s., et al.. High coloration performance of electrochromic devices assembled with electrolytes based on a branched boronate ester polymer and lithium perchlorate salt. Thin Solid Films, 2006,514,258-66. 

Stability tests performed in sandwich-type cells containing the dyes adsorbed on Sn02/Sb electrodes demonstrated a high stability, with optical density changes lower than 2% after cycling the electrochromic device 20000 times between -0.5 and +0.5 V. 

The potential benefits of using ionic liquids as electrolytes in conducting polymer devices have been investigated by a number of authors in recent years, for applications such as actuators [8-17], supercapacitors [18-20], electrochromic devices [12, 21] and solar cells [22], with significant improvements in lifetimes and device performance reported. 

The development of high performance electrolytes is an important task in the production of devices for electric energy storage and delivery such as lithium ion batteries, capacitors, and electrochromic devices. Carbonate-based materials are one of the liquid electrolytes. Carbonate-based liquid electrolytes are now commonly used for the economical lithium ion batteries [31]. The solution of carbonate and lithium salts exhibits high ionic conductivity, on the order of 10-3 S cm-1 at ambient temperature. 

Although various electrochromic devices have been demonstrated, their performance still needs to be drastically improved. This will require a major research and development effort. On the other hand, the fiber optic metal hydride hydrogen sensor already shows that metal hydride applications may provide a clear advantage over competing systems. 

Nanomaterials of undoped vanadia employed in electrochromic studies include nanowires [35-37], inverse opals [34], and mesoporous films [38]. Similar attempts were undertaken for NiO devices [39 2]. Although these recent attempts brought about an improvement in electrochromic performance, the reported switching times remained 1-2 orders of magnitude above the desired video rate of 24 frames per second [34-38]. This is mainly due to the use of sub-optimal MO morphologies in terms of their structural dimension, connectivity and integrity. 

To investigate the electrochromic performance, transparent devices were assembled similarly to Sect. 5.2.3 by capping the prepared NiO films with a FTO counter electrode using a precut thermoplastic gasket as spacer, infiltration with 1M KOH(aq) electrolyte, insertion of an Ag/AgCl wire as reference electrode, and finally sealing the device with epoxy glue. 

As naturally abundant and low-cost semiconductor, NiO is widely used in electrochromic windows [20], batteries [21], supercapacitors [22], and sensors [23], While all these applications benefit from an interconnected, three-dimensional NiO nanostructure that combines a high specific surface area with a good electric conductivity, the performance enhancement becomes vividly evident as an increased coloration contrast and improved switching behavior when applied in electrochromic devices. NiO nanomaterials recently employed in electrochromic studies include nanocomposites [24], inverse opals [25], macroporous [26] and mesoporous films [27-29],... 

To investigate the effect of the nanostructure on the electrochromic performance of NiO, transparent devices were assembled from nontemplated and DG-structured films with a FTO counter electrode and a 1M KOH(aq) electrolyte, see Fig. 6.9a. The active electrode material used was limited in area to 0.95mm. During the nickel electroplating process limiting the deposition area improve the control and quality of the deposit. 

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