The synthesis of high-molecular-weight bioderived polycarbonates via green routes and regulation of molecular weight is of great significance and is highly challenging. Herein, a green sequential approach toward the synthesis of bio-derived polycarbonates with adjustable molecular weights from isosorbide and dimethyl carbonate (DMC) has been developed by employing ionic liquids (ILs) as a class of eco-friendly catalysts. The structures of IL catalysts can be designed readily to control the molecular weight of isosorbide-derived polycarbonates (PIC), which is an attractive advantage of IL catalysts instead of the conventional metal-containing catalysts. In the presence of the [Bmim][4-I-Phen] catalyst, the PIC weight-average molecular weight (M_w) can reach 50 300 g mol⁻¹. By the combination of the experimental results and DFT calculations, an IL anion–cation synergistic catalytic polymerization mechanism has been proposed, which reveals the nucleophile–electrophile dual activation by H-bonds and charge–charge interactions in catalyzing the formation of PIC. The significance of this study is that it provides guidance for developing IL catalysts for synthesizing higher molecular weight polycarbonates, thereby conveniently leading to a variety of polymers with tunable properties.

A comprehensive overview of the cutting-edge applications of ionic liquids in new energy, electronic information chemicals and biotechnologies.

All-visible-light controlled fluorescence switching is more promising for bioimaging. Constructing dual-color fluorescent bisthienylethene (BTE) systems are quite challenging. Here, all-visible-light triggered dual-color fluorescence switching was achieved in a color-specific switching manner in a solid-state by associating the photochromic BTE core with a blue emissive phenanthroimidazole (PI) unit. Unique emission behaviour caused by J-aggregation of the coplanar PI unit was crucial, which suggested a novel strategy for constructing dual-color fluorescent photoswitching. Moreover, a ‘turn-off‘ fluorescence photoswitching was demonstrated in solution and PMMA films owing to the energy transfer from the PI moiety to a ring-closed isomer of the BTE moiety. Remarkably, an all-visible-light patterning application for information storage medium was developed with these compounds. BTE-P1 was successfully utilized in cellular imaging for efficient fluorescence switching.

The development of a sustainable process for producing high-performance photoresists is desirable yet challenging. In this study, we proposed an ionic liquid (IL)-assisted approach for preparing a photoresist by copolymerizing 1-butyl-3-vinyl imidazolium bromide (VBIMBr) and acrylates. The hydrophilic nature of VBIMBr improved the adhesion between the photoresist and the hydrophilic Si substrate, eliminating the use of hazardous hexamethyldisilazane (HMDS) vapor. This IL-based photoresist could be developed with water instead of the corrosive developer tetramethylammonium hydroxide (TMAH). Furthermore, the interaction between VBMIBr and H⁺ effectively reduced acid diffusion and line edge roughness (LER), resulting in superior lithography performance compared to traditional acrylate photoresists. This IL-based photoresist exhibited an excellent response to both deep ultraviolet lithography (DUV) and electron beam lithography (EBL), achieving a line resolution of 0.5 μm and 100 nm, respectively. Meanwhile, the lithography kinetics and mechanism were further investigated. Overall, this eco-friendly IL-assisted strategy provides a promising solution for producing high-performance photoresists, even in electrical applications. Additionally, this IL-assisted approach has the potential for widespread use in the development of advanced materials.

Conducting polymers are promising candidate materials in next-generation electrochromic applications due to their multicolour changes, flexible and large-scale production capability; however, poor cycling stability and relatively low optical modulation limit their widespread application. In this article, a simple electrochemical deposition method is used to create a polyaniline (PANI)/Au nanorods composite electrochromic film on ITO glass as an electrode. This PANI/Au nanorods composite film has better electrochromic properties than the straight PANI film. Moreover, the electrochromic device (ECD) was successfully fabricated by PANI/Au nanorods composite film as anode and poly(3,4-ethyloxylthiophene) as the cathode. This resultant device exhibits perfect electrochromic performance, including higher optical modulation (56%), a faster response time (0.6 s for bleaching and 0.9 s for colouring) and good cycling stability (sustained 85% after 6750 cycles). Notably, the geometric structure of the film is formed by the Au nanorods coated with PANI, which not only can provide transport channel and ion storage space but also improving the conductivity. In addition, the composite structure can provide larger surface area and benefit the electrolyte ions insertion and extraction from the composite electrode film. The rational design of stacking nanocomposites on electrodes may be a useful method for fabricating high-performance ECDs.