| Title: | Joule Heating-Driven Transformation of Hard-Carbons to Onion-like Carbon Monoliths for Efficient Capture of Volatile Organic Compounds |
| Author(s): | Dwivedi I; Subramaniam C; |
| Address: | "Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, Maharashtra, India" |
| DOI: | 10.1021/acsmaterialsau.1c00062 |
| ISSN/ISBN: | 2694-2461 (Electronic) 2694-2461 (Linking) |
| Abstract: | "Soft graphitizable carbon-based multifunctional nanomaterials have found versatile applications ranging from energy storage to quantum computing. In contrast, their hard-carbon analogues have been poorly investigated from both fundamental and application-oriented perspectives. The predominant challenges have been (a) the lack of approaches to fabricate porous hard-carbons and (b) their thermally nongraphitizable nature, leading to inaccessibility for several potential applications. In this direction, we present design principles for fabrication of porous hard-carbon-based nanostructured carbon florets (NCFs) with a highly accessible surface area ( approximately 936 m(2)/g), rivalling their soft-carbon counterparts. Subjecting such thermally stable hard-carbons to a synergistic combination of an electric field and Joule heating drives their transformation to free-standing macroscopic monoliths composed of onion-like carbons (OLCMs). This represents the first such structural transformation observed in sp(2)-based hard-carbon NCFs to sp(2)-networked OLCMs. Micro-Raman spectroscopy establishes the simultaneous increase in the intensity of D-, 2D-, and D + G-bands at 1341, 2712, and 2936 cm(-1) and is correlated to the reorganization in the disordered graphitic domains of NCFs to curved concentric nested spheres in OLCMs. This therefore completely precludes the formation of a nanodiamond core that has been consistently observed in all previously reported OLCs. The Joule heating-driven formation of OLCMs is accompanied by approximately 5700% enhancement in electrical conductivity that is brought about by the fusion of outermost graphitic shells of OLCs to result in monolithic OLC structures (OLCMs). The porous and inter-networked OLCMs exhibit an excellent adsorption-based capture of volatile organic compounds such as toluene at high efficiencies ( approximately 99%) over a concentration range (0.22-1.86 ppm) that is relevant for direct applications such as smoke filters in cigarettes" |
| Notes: | "PubMed-not-MEDLINEDwivedi, Itisha Subramaniam, Chandramouli eng 2021/11/30 ACS Mater Au. 2021 Nov 30; 2(2):154-162. doi: 10.1021/acsmaterialsau.1c00062. eCollection 2022 Mar 9" |
