Glucose derived ionothermal carbons with tailor-made porosity

Abstract

An ionothermal synthesis strategy to obtain a set of glucose derived carbons with tailored pore system is demonstrated. The biomass derived materials possess high surface areas and large total pore volumes with values up to 2160 m2 g−1 and 1.74 cm3 g−1, respectively. The tailoring of the pore system is realized by simply changing the molar composition of the KCl/ZnCl2 mixture which serves as combined solvent-porogen. Increasing \KCl\} contents result in a continuous pore opening and rising pore volume leading to enhanced mass transport porosity. Those effects are accompanied by a linear decrease of the specific surface area which allows for the preparation of porous carbons of high and predictable surface areas between 2160 and 960 m2 g−1. Experiments exemplarily shown for the application as supercapacitor electrodes, the different materials show a decreased gravimetric capacity, but enhanced capacity retention as well as improved areal capacity with incresased \{KCl\ content nicely supporting the improved mass transport properties

Ionothermal template transformations for preparation of tubular porous nitrogen doped carbons

“…with very high alkali chloride amounts) also caused additional macrotemplating due to remaining solid, dispersed salt particles in the carbonizing reaction mixture. 23,33 This recent finding inspired us to investigate the utilization of intermediately crystallizing salt phases as structured templates. In situ formation of templates is well-known from soft templating, e.g.…”

Hierarchically porous carbon derived from the activation of waste chestnut shells by potassium bicarbonate (KHCO 3 ) for high‐performance supercapacitor electrode

“…Figure 1A displays the SEM image of the as-prepared carbon through calcination of chestnut shell without addition of KHCO 3 . [30][31][32][33] With higher magnification, the elaborate macropores are clearly displayed in Figure 1E. The micro fibers with a length of hundreds of micrometers grow on the surface of the bulky sheet.…”

Nanoporous Carbon Synthesis: An Old Story with Exciting New Chapters

“…In fact, the use of ionothermal/molten salt process can be linked either to the preparation of carbon materials with incipient porosity obtained at temperatures ≈ 200°C (ionothermal carbonization-ITC) [102] or to the preparation of porous carbons by a two-step process including the previously mentioned ITC followed by a thermal treatment of the ionothermal derived carbon at high temperatures (attaining 1000°C or more) [103,104]. Ionothermal/molten salt process is also considered in the case where the mixture of the carbon precursor and the ionic solvent is directly thermally treated at high temperature [105,106]. , and the authors demonstrated the influence of the ionic liquid nature on the development of mainly microporous or micro + mesoporous materials [107].…”