{"title":"Highly Efficient Aqueous Symmetric Redox Electrochemical Capacitor Based on UiO-66-NH2–Polyaniline Composite Powering Yellow LEDs","authors":"Krishna Chattopadhyay, Ankur Basak, Gi-Bbeum Lee, Manas Mandal, Changwoon Nah, Dilip K. Maiti","doi":"10.1021/acsaem.4c01646","DOIUrl":null,"url":null,"abstract":"Metal–organic frameworks (MOFs) have garnered considerable attention as supercapacitor electrode materials due to their large specific surface area and adjustable pore structure, but they are practically limited by poor conductivity. To address this limitation, in this study, the MOF, UiO-66-NH<sub>2</sub>, is modified with a conducting polymer, polyaniline (PANI), through <i>in situ</i> polymerization. In the composite, the MOF unit enriches the PANI polymers with a large number of electroactive centers, facilitating the electron transfer process. Among the as-synthesized composites, UP0.1 exhibited best electrochemical performance with a high specific capacitance of 462.2 F g<sup>–1</sup> at a specific current of 1 A g<sup>–1</sup> in a 2 M KOH electrolyte. Introducing the redox-active substance K<sub>4</sub>[Fe(CN)<sub>6</sub>] into KOH resulted in reduced diffusion and charge transfer resistances, leading to an enhanced specific capacitance value of 859.5 F g<sup>–1</sup> at the same current. The as-fabricated aqueous symmetric supercapacitor device can be operated up to 1.4 V without any oxygen evolution reaction, exhibiting a high specific capacitance of 252.3 F g<sup>–1</sup>, which is equivalent to the areal capacitance of 1.3 F cm<sup>–2</sup> at a specific current of 0.8 A g<sup>–1</sup>. The device achieved a high specific energy of 68.7 W h kg<sup>–1</sup> at a high specific power of 2.24 kW kg<sup>–1</sup>, along with good electrochemical stability. Two devices connected in series were used to demonstrate the practical application using yellow LEDs, paving the way toward the futuristic production of energy storage electronics.","PeriodicalId":4,"journal":{"name":"ACS Applied Energy Materials","volume":null,"pages":null},"PeriodicalIF":5.4000,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"ACS Applied Energy Materials","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.1021/acsaem.4c01646","RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
Metal–organic frameworks (MOFs) have garnered considerable attention as supercapacitor electrode materials due to their large specific surface area and adjustable pore structure, but they are practically limited by poor conductivity. To address this limitation, in this study, the MOF, UiO-66-NH2, is modified with a conducting polymer, polyaniline (PANI), through in situ polymerization. In the composite, the MOF unit enriches the PANI polymers with a large number of electroactive centers, facilitating the electron transfer process. Among the as-synthesized composites, UP0.1 exhibited best electrochemical performance with a high specific capacitance of 462.2 F g–1 at a specific current of 1 A g–1 in a 2 M KOH electrolyte. Introducing the redox-active substance K4[Fe(CN)6] into KOH resulted in reduced diffusion and charge transfer resistances, leading to an enhanced specific capacitance value of 859.5 F g–1 at the same current. The as-fabricated aqueous symmetric supercapacitor device can be operated up to 1.4 V without any oxygen evolution reaction, exhibiting a high specific capacitance of 252.3 F g–1, which is equivalent to the areal capacitance of 1.3 F cm–2 at a specific current of 0.8 A g–1. The device achieved a high specific energy of 68.7 W h kg–1 at a high specific power of 2.24 kW kg–1, along with good electrochemical stability. Two devices connected in series were used to demonstrate the practical application using yellow LEDs, paving the way toward the futuristic production of energy storage electronics.
基于 UiO-66-NH2-Polyaniline 复合材料的高效水基对称氧化还原电化学电容器为黄色 LED 供电
金属有机框架(MOF)因其较大的比表面积和可调节的孔隙结构而作为超级电容器电极材料备受关注,但实际上却因导电性差而受到限制。为了解决这一局限性,本研究通过原位聚合,用导电聚合物聚苯胺(PANI)修饰了 MOF UiO-66-NH2。在复合材料中,MOF 单元使 PANI 聚合物富含大量电活性中心,从而促进了电子转移过程。在合成的复合材料中,UP0.1 的电化学性能最好,在 2 M KOH 电解液中,比电流为 1 A g-1 时,比电容高达 462.2 F g-1。在 KOH 中引入氧化还原活性物质 K4[Fe(CN)6]可降低扩散和电荷转移电阻,从而在相同电流下将比电容值提高到 859.5 F g-1。所制备的水基对称超级电容器装置可在高达 1.4 V 的电压下运行,且不会发生任何氧进化反应,比电容高达 252.3 F g-1,相当于在 0.8 A g-1 的比电流下 1.3 F cm-2 的等面积电容。在 2.24 kW kg-1 的高比功率下,该装置获得了 68.7 W h kg-1 的高比能量和良好的电化学稳定性。利用两个串联装置演示了黄色 LED 的实际应用,为未来生产储能电子产品铺平了道路。
期刊介绍:
ACS Applied Energy Materials is an interdisciplinary journal publishing original research covering all aspects of materials, engineering, chemistry, physics and biology relevant to energy conversion and storage. The journal is devoted to reports of new and original experimental and theoretical research of an applied nature that integrate knowledge in the areas of materials, engineering, physics, bioscience, and chemistry into important energy applications.