Hierarchical porous carbon spheres derived from larch sawdust via spray pyrolysis and soft-templating method for supercapacitors

Abstract

Hierarchical porous carbon spheres (PCSs) with a tunable pore structure were prepared from larch sawdust via spray pyrolysis and a soft-templating method. Decomposition of the soft template, i.e., Pluronic F127, in the carbonization step led to formation of a hierarchical porous structure with mesopores and macropores. Swelling of the core, presumably predominantly of the poly(propylene oxide) component, was induced by evaporation of water. This led to the generation of ultra-large mesopores and macropores. The surface morphology and pore structure of the carbon spheres were controlled by varying the F127 concentration. The PCSs morphologies changed from smooth to rough with increasing addition of F127, and the particle sizes became more uniform. When the content of F127 reached 0.075 (ratio of F127/ larch-based resin), the prepared PCSs (PCSs-0.075) had structural integrity, a high surface area (760.3 m 2 g −1 ), and a large pore volume (0.59 cm 3 g −1 ), and contained a combination of micropores, macropores, and mesopores. X-ray diffraction and Raman spectroscopy showed that addition of F127 had little effect on the graphitic degree of the samples. Because of its hierarchical pore structure and high surface area, the optimized sample, i.e., PCSs-0.075, gave an excellent electrochemical performance as an electrode material for supercapacitors, with a specific capacitance of 338.8 F g −1 at 0.2 A g −1 and a good rate capability (165.1 F g −1 at 5 A g −1 ) in 6 M KOH solution. These PCSs with mesopores and macropores, which facilitate penetration of ions into pores, are promising as efficient electrode materials for supercapacitors.

Engineered/designer hierarchical porous carbon materials for organic pollutant removal from water and wastewater: A critical review

“…In addition, CaCO3 [40] and Na2CO3 [41] are also commonly used as porogen of hard template. Soft templates are typically organic polymers that can be thermally decomposed and removed [1,42,43]. These thermally decomposed polymers can be polystyrene (PS) [44,45], polymethyl methacrylate (PMMA) [46], polyurethane (PU) and surfactants [47].…”

Recent Advances in the Fabrication and Functionalization of Nanostructured Carbon Spheres for Energy Storage Applications

“…In some studies, ordered mesoporous CSs have been fabricated by a simple one-step process. Song et al synthesized hierarchical porous CSs using Pluronic F127 as a soft template and biomass (e.g., larch sawdust) as the carbon precursor via a spray pyrolysis method (Song et al, 2019). (Fei et al, 2020).…”

N-doped CNTs wrapped sulfur-loaded hierarchical porous carbon cathode for Li–sulfur battery studies

“…To improve the connement ability, highly porous carbon hosts are required, so that they can have high adsorption capacity along with large storage space for sulfur and afford large buffer volume to the sulfur cathode. [31][32][33] Having ordered pores with different diameters, hierarchically porous carbon (PC) materials exhibit high performances in various applications such as energy storage, deionization, CO 2 capture, catalyst, etc. [34][35][36][37][38] The porous architectures of the host can accommodate large buffering volumes to sulfur and trap the polysulde species during Li + reactions.…”