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Discovering and constructing molecular functionality platforms for materials chemistry innovation has been a persistent target in the fields of chemistry, materials, and engineering. Around this task, basic scientific questions can be asked, novel functional materials can be synthesized, and efficient system functionality can be established. Poly(ionic liquid)s (PILs) have attracted growing interest far beyond polymer science and are now considered an interdisciplinary crossing point between multiple research areas due to their designable chemical structure, intriguing physicochemical properties, and broad and diverse applications. Recently, we discovered that 1,2,4-triazolium-type PILs show enhanced performance profiles, which are due to stronger and more abundant supramolecular interactions ranging from hydrogen bonding to metal coordination, when compared with structurally similar imidazolium counterparts. This phenomenon in our view can be related to the smart hydrogen atoms (SHAs), that is, any proton that binds to the carbon in the N-heterocyclic cations of 1,2,4-triazolium-type PILs. The replacement of one carbon by an electron-withdrawing nitrogen atom in the broadly studied heterocyclic imidazolium ring will further polarize the C–H bond (especially for C5–H) of the resultant 1,2,4-triazolium cation and establish new chemical tools for materials design. For instance, the H-bond-donating strength of the SHA, as well as its Bro̷nsted acidity, is increased. Furthermore, polycarbene complexes can be readily formed even in the presence of weak or medium bases, which is by contrast rather challenging for imidazolium-type PILs. The combination of SHAs with the intrinsic features of heterocyclic cation-functionalized PILs (e.g., N-coordination capability and polymeric multibinding effects) enables new phenomena and therefore innovative materials applications. In this Account, recent progress on SHAs is presented. SHA-related applications in several research branche

Heteroatom-doped porous carbon materials (HPCMs) have found extensive applications in adsorption/separation, organic catalysis, sensing, and energy conversion/storage. The judicious choice of carbon precursors is crucial for the manufacture of HPCMs with specific usages and maximization of their functions. In this regard, polymers as precursors have demonstrated great promise because of their versatile molecular and nanoscale structures, modulatable chemical composition, and rich processing techniques to generate textures that, in combination with proper solid-state chemistry, can be maintained throughout carbonization. This Review comprehensively surveys the progress in polymer-derived functional HPCMs in terms of how to produce and control their porosities, heteroatom doping effects, and morphologies and their related use. First, we summarize and discuss synthetic approaches, including hard and soft templating methods as well as direct synthesis strategies employing polymers to control the pores and/or heteroatoms in HPCMs. Second, we summarize the heteroatom doping effects on the thermal stability, electronic and optical properties, and surface chemistry of HPCMs. Specifically, the heteroatom doping effect, which involves both single-type heteroatom doping and codoping of two or more types of heteroatoms into the carbon network, is discussed. Considering the significance of the morphologies of HPCMs in their application spectrum, potential choices of suitable polymeric precursors and strategies to precisely regulate the morphologies of HPCMs are presented. Finally, we provide our perspective on how to predefine the structures of HPCMs by using polymers to realize their potential applications in the current fields of energy generation/conversion and environmental remediation. We believe that these analyses and deductions are valuable for a systematic understanding of polymer-derived carbon materials and will serve as a source of inspiration for the design of futur

Poly(ionic liquid)s (PILs), as an innovative class of polyelectrolytes, are composed of polymeric backbones with IL species in each repeating unit. The combined merits of the polymers and ILs make them promising materials for composites in materials science. Particularly, the integration of PILs with functional substances (PIL composites) opens up a new dimension in utilizing ionic polymers by offering novel properties and improved functions, which impacts multiple subfields of our chemical society. This review summarizes recent developments of PIL composites with a special emphasis on the preparation techniques that are based on the intrinsic properties of the PILs and the synergistic effects between the PILs and substances of interest for diverse applications.

This poster will present two topics that are active in our research group, the porous poly(ionic liquid) membranes and the ionic organic cages. Functional nanoporous polymer membranes with expanded surface area can be applied in broad fields, including separation, filtration, catalysis and energy applications. There are a number of established methods for the preparation of nanoporous membranes using neutral or weakly charged polymers. Although, fabrication of nanoporous polymer membranes from strong polyelectrolytes is far more difficult, we present our approach to nanoporous polyelectrolyte membranes by using poly(ionic liquid)s. [1] Poly(ionic liquid)s (PILs) are the polymerization products of ionic liquids, which combine certain properties and functions of polymeric materials (e,g. durability and good processability) and ILs (e.g. ion conductivity and thermal stability). We have exploited these favorable properties in the fabrication of nanoporous membranes from imidazolium based PILs through electrostatic complexation of PILs with polyacids. [2,3] The porous structure forms as a result of microphase separation of the hydrophobic PIL chains from the aqueous environment and is simultaneously stabilized by ionically crosslinked networks between the cationic PIL and the negatively charged neutralized polyacids. The membrane pore sizes can be tuned from nano- to micrometer scale by varying the degree of electrostatic complexation. In this meeting, we will update you with our latest progress in making nanoparticle-decorated nanoporous PIL membranes in a single step. In the ionic organic cage part, we present our work about operating ionic organic cages (I-cages) to enclose small noble metal clusters (MCs) with adaptivity to water-oil phase. Organic molecular cages are a kind of multifunctional materials with molecular solubility, intrinsic open channels and unique ability to accommodate guest objects such as (MCs). [4] Herein, we report physical confinement of small

A nanoporous material bearing a high ion density and inherent organic radical character was synthesized by a facile one-pot process, which exhibits photo-, piezo- and chemochromism, driven by the diverse electron transfer processes between the acceptor framework and different electron donors. The responsive behavior is useful for its sensing application, as demonstrated here for pressure, anion and gas sensing.