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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 m(2) 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. (C) 2019 Elsevier Inc. All rights reserved.