Ultrafast Metal-Free Microsupercapacitor Arrays Directly Store Instantaneous High-Voltage Electricity from Mechanical Energy Harvesters.

Harvesting renewable mechanical energy is envisioned as a promising and sustainable way for power generation. Many recent mechanical energy harvesters are able to produce instantaneous (pulsed) electricity with a high peak voltage of over 100 V. However, directly storing such irregular high-voltage pulse electricity remains a great challenge.

Room-Temperature Self-Standing Cellulose-Based Hydrogel Electrolytes for Electrochemical Devices.

The trend of research towards more sustainable materials is pushing the application of biopolymers in a variety of unexplored fields. In this regard, hydrogels are attracting significant attention as electrolytes for flexible electrochemical devices thanks to their combination of ionic conductivity and mechanical properties. In this context, we present the use of cellulose-based hydrogels as aqueous electrolytes for electrochemical devices.

All-in-One Gel-Based Electrochromic Devices: Strengths and Recent Developments.

Electrochromic devices (ECDs) have aroused great interest because of their potential applicability in displays and smart systems, including windows, rearview mirrors, and helmet visors. In the last decades, different device structures and materials have been proposed to meet the requirements of commercial applications to boost market entry. To this end, employing simple device architectures and achieving a competitive electrolyte are crucial to accomplish easily implementable, high-performance ECDs.

Colorless to Neutral Color Electrochromic Devices Based on Asymmetric Viologens.

Electrochromic materials have extensively been investigated because of their potential fields of application, with a significant growing interest in expanding the provided colorations. However, among all palette of colors, colorless electrochromic devices (ECDs) that provide neutral-grayish colorations with a simple configuration remain a key challenge. The present study reports on the synthesis of asymmetrically 1-alkyl-1'-aryl-substituted viologens and their incorporation in PVA-borax gel polyelectrolytes for ECDs that constitute the simplest device architecture (glass/TCO/EC gel/TCO/glass).

Multicolor Electrochromics: Rainbow-Like Devices.

Stimuli-responsive reversible coloration-change materials represent a highly demanded type of smart systems useful for a wide variety of applications, with a significant growing interest in multicolor abilities. In particular, electrochromic materials have received a great deal of attention due to their versatility and broad range of industrial uses. However, most of the existing electrochromic technologies provide a single coloration, while achieving multiple colors based on simple approaches remains a challenge.