Polysiloxane microspheres encapsulated in carbon allotropes: A promising material for supercapacitor and carbon dioxide capture

Prabu Moni; Westerley Fernandes Chaves; Michaela Wilhelm; Kurosch Rezwan

doi:10.1016/j.jcis.2019.01.087

Polysiloxane microspheres encapsulated in carbon allotropes: A promising material for supercapacitor and carbon dioxide capture

J Colloid Interface Sci. 2019 Apr 15:542:91-101. doi: 10.1016/j.jcis.2019.01.087. Epub 2019 Jan 22.

Authors

Prabu Moni¹, Westerley Fernandes Chaves¹, Michaela Wilhelm², Kurosch Rezwan³

Affiliations

¹ University of Bremen, Advanced Ceramics, Am Biologischen Garten 2, IW3, 28359 Bremen, Germany.
² University of Bremen, Advanced Ceramics, Am Biologischen Garten 2, IW3, 28359 Bremen, Germany. Electronic address: mwilhelm@uni-bremen.de.
³ University of Bremen, Advanced Ceramics, Am Biologischen Garten 2, IW3, 28359 Bremen, Germany; University of Bremen, MAPEX Center for Materials and Processes, Bibliothekstraße 1, 28359 Bremen, Germany.

PMID: 30735891
DOI: 10.1016/j.jcis.2019.01.087

Abstract

Recently, hierarchical porous materials have received tremendous attention in electrochemical supercapacitors and CO₂ adsorption. Both areas of application have a positive impact on global warming by reducing CO₂ emissions to the atmosphere. Herein, we synthesized new silica-based ceramic monoliths composed of polysiloxane microspheres sheathed by carbon allotropes (Graphene or MWCNT) and metal nanoparticles. The as-synthesized hybrid ceramics show a high specific surface area of 540 m² g^-1 with hierarchical micro-/meso-/macroporous structures. With the structural benefits, the obtained ceramics exhibits excellent performance in supercapacitors and for CO₂ adsorption as probed in this study. As an electrode material for supercapacitor, the hybrid ceramics delivered the specific capacitance of 93 F/g at 2 mV s^-1 in 0.5 M KOH electrolyte solution with a capacity retention of 88% after 50 cycles. Further, as a solid adsorbent, the hybrid ceramics shows the maximum CO₂ adsorption capacity of 2 mmol g^-1 at 100 kPa equilibrium pressure and 303 K, while maintaining 98% capacity retention after 10 cycles. Thus, the hybrid ceramics with its unusual properties make them a promising candidate for both, supercapacitors and CO₂ capture in the sheer physical adsorption process.

Keywords: CO(2) adsorption; Carbon allotropes; Emulsion; Hybrid ceramics; Supercapacitor.