Chemistry of Materials最新文献

The rapid advancement of flexible electronic technologies, including wearable electronics, implantable medical devices, and smart textiles, has spurred a growing interest in developing biocompatible, high-performance, and flexible energy-storage systems. Among these, fiber-shaped supercapacitors have emerged as promising candidates for next-generation flexible power sources due to their high power density, long cycle life, and excellent flexibility. In this regard, nanomaterial-based composites have been developed to further enhance their performance and practical applicability. This review systematically summarizes recent research progress in fibrous supercapacitors, with a special emphasis on design strategies and performance optimization related to established fabrication methods (such as wet spinning and coating), typical structural configurations (parallel, twisted, and coaxial designs), and key electrode materials (including metal wires, carbon-based substances, graphene, and MXene). Furthermore, this article highlights cutting-edge applications of fibrous supercapacitors in self-powered systems, wearable electronics, and biomedical devices, and discusses the prevailing challenges and future directions for their large-scale fabrication, system integration, and practical deployment.

Conjugated polyelectrolytes (CPEs) are a distinct class of polymers that feature a π-conjugated backbone and pendant ionic groups, which confers them unique properties. In particular, since the discovery, during their purification in water, that some CPEs have the ability to be self-doped, they have attracted increasing interest from the organic electronics community. More recently, a self-acid doping mechanism was proposed after it was proven that the degree of doping can be modulated by the addition of an acid or a base. However, the explanation of both the self-doping and self-acid doping processes remains ambiguous, and their investigation continues to present significant challenges. In this work, we address the problem through a combination of experimental and computational techniques, including spectroscopy (UV–vis and Raman) and electrochemistry measurements in conjunction with DFT calculations and molecular dynamics simulations. We performed a comprehensive investigation into the self-doping mechanism of CPE-2K, poly [2,6-(4,4-bis-potassium butanylsulfonate-4H-cyclopenta-[2.1-b:3,4-b′] dithiophene)-alt-4,7-(2,1,3-benzothiazole)], and its homologue with only one alkyl ionic chain, CPE-K. Our findings point to a framework that integrates the self- and self-acid doping mechanisms into a unified one, in which backbone aggregation acts as the driving force.

Operando Raman spectroscopy measurements are becoming increasingly common in battery materials research. Yet, from a measurement science perspective, there is little consistency in the literature in terms of experimental design, and methodological validity is often not thoroughly considered. In this paper, we experimentally critique the most commonly used operando Raman approach to examining commercial battery electrodes─the “through-hole” method, in which optical access to the electrode under investigation is gained via a hole in the opposing electrode and separator. We benchmark the electrochemical performance of the operando cell against a conventional 2032 coin cell, identifying critical factors that can negatively impact electrochemical performance. Using the well-established lithiation of graphite as a test system, we demonstrate systematic spatial variations in the localized operando Raman response upon moving from the center to the edge of the optical access hole. These variations highlight the importance of sampling location and statistical analysis in connecting local spectral metrics with the global electrochemical characteristics of the cell. Secondary ion mass spectrometry imaging also indicates spatial variations in surface chemistry resulting from the reduced stack pressure at the position of the optical window, which is an important consideration when interpreting the observed operando Raman response.