Graphene as an efficient interfacial layer for electrochromic devices

Recent Advances in Inorganic Electrochromic Materials from Synthesis to Applications: Critical Review on Functional Chemistry and Structure Engineering

For the assembly of electrochromic devices (ECDs) generally with multilayer structures, supportive components usually are needed to be incorporated with EC materials. The reasonable project and development of ECDs will achieve broad expected applications. In this study, we reviewed several impressive methods to design and fabricate ECDs with high-performance and versatility based on recent frontier research. The first part of the review is centered on the desirability and strengthening mechanism of nanostructured inorganic EC materials. The second part illustrates the recent advances in transparent conductors. We then summarize the demands and means to modify the formation of electrolytes for practicable ECDs. Moreover, efforts to increase the compatibility with the EC layer and ion capacity are delineated. In the end, the application prospects of inorganic ECDs are further explored, which offers a guideline for the industrialization process of ECDs.

Transparent Conductive Electrodes Based on Graphene-Related Materials

Transparent conducting electrodes (TCEs) are the most important key component in photovoltaic and display technology. In particular, graphene has been considered as a viable substitute for indium tin oxide (ITO) due to its optical transparency, excellent electrical conductivity, and chemical stability. The outstanding mechanical strength of graphene also provides an opportunity to apply it as a flexible electrode in wearable electronic devices. At the early stage of the development, TCE films that were produced only with graphene or graphene oxide (GO) were mainly reported. However, since then, the hybrid structure of graphene or GO mixed with other TCE materials has been investigated to further improve TCE performance by complementing the shortcomings of each material. This review provides a summary of the fabrication technology and the performance of various TCE films prepared with graphene-related materials, including graphene that is grown by chemical vapor deposition (CVD) and GO or reduced GO (rGO) dispersed solution and their composite with other TCE materials, such as carbon nanotubes, metal nanowires, and other conductive organic/inorganic material. Finally, several representative applications of the graphene-based TCE films are introduced, including solar cells, organic light-emitting diodes (OLEDs), and electrochromic devices.

Tungsten Trioxide Doped with CdSe Quantum Dots for Smart Windows

Nanocrystal quantum dots (QDs) provide tunable optoelectronic properties on the basis of their dimension. CdSe QDs, which are size-dependent colloidal nanocrystals, are used for efficient electrochromic devices owing to their unique properties in modulating quantum confinement, resulting in enhanced electron insertion during the electrochromic process. Incorporating a well-known metal oxide electrochromic material such as WO₃ into CdSe QDs enhances the redox process. Herein, we propose a facile method for producing and optimizing CdSe QDs doped in WO₃. The fabrication of the electrochromic film involves a solution and annealing process. Moreover, the effect of the QD size to optimize the electrochromic layer is studied. As a result, the coloration efficiency of WO₃ and optimized CdSe QD-WO₃ are obtained as 68.6 and 112.3 cm²/C, respectively. Thus, size-tunable nanocrystal QDs combined with a metal oxide yield high-performance electrochromic devices and are promising candidates for producing smart windows.

Facile preparation of aqueous suspensions of WO3/sulfonated PEDOT hybrid nanoparticles for electrochromic applications

An aqueous suspension of WO₃/PEDTS nanoparticles is facilely prepared, giving the hybrid electrochromic devices an enhanced optical contrast and electrochemical stability.