Hybridization of a Polymer inside the Pores of Activated Carbon and Pore Structural Characterization

Abstract

A polymer, polydicyclopentadiene (PDCPD), is hybridized within the pores of activated carbon (AC) that has micropores and mesopores of ∼4 nm. The hybridization is performed via gas-phase adsorption of dicyclopentadiene (DCPD) on AC and subsequent thermal polymerization. It is confirmed from a variety of analytical techniques, such as scanning and transmittance electron microscopies, a nitrogen adsorption− desorption analysis, and electrochemical measurements, that there is little PDCPD on the particle surfaces of AC. The nitrogen adsorption−desorption measurement of the resulting AC/PDCPD hybrids reveals that the micropore and mesopore volumes decrease with the increasing amount of the hybridized PDCPD. Moreover, the electric double-layer capacitance decreases and the diffusion resistance increases with the increasing amount of the hybridized PDCPD. These results cannot be explained by a micropore filling model where micropores are first filled with PDCPD. Our experimental results reveal that PDCPD does not exist as layers covering the pore walls of AC but exists as agglomerates uniformly distributing inside both micropores and mesopores.

Synthesis of Polynorbornadiene within the Pores of Activated Carbons: Effects on EDLC and Hydrogen Adsorption Performances

“…The results of the AC-4/PNBD hybrids are in good agreement with the results of the hybrids prepared from AC-4 and polydicyclopentadiene (PDCPD) . We have previously reported the hybridization of PDCPD within the pores of AC-4, and three models of PDCPD were considered for the AC-4/PDCPD hybrids, as shown in Figure : layer (a), agglomeration (b), and micropore-filling (c) models.…”

“…, ∼2 nm) and AC-4 with both micropores and mesopores below 4 nm . Unless the amount of NBD exceeds the saturation amount of AC, NBD is completely adsorbed on AC by using a gas-phase adsorption technique. , Therefore, the amount of the adsorbed NBD can be accurately controlled. The NBD-adsorbed ACs are denoted as AC-2/NBD ( X ) and AC-4/NBD ( X ) for the samples prepared using AC-2 and AC-4, respectively, where X represents the amount of the adsorbed NBD per 1 g of AC ( i.e.…”

“…The dried AC was added to a glass vial under a nitrogen atmosphere, and the mass of the dried AC was calculated by the weight difference of the glass ampoule. Subsequently, NBD (Tokyo Chemical Industry Co., Ltd.) was added to a glass tube, and the glass tube was frozen by liquid nitrogen so as not to evaporate during a subsequent procedure . The amount of NBD was adjusted to make accurate AC/NBD weight ratios.…”

“…The following characterizations were done as described in ref : nitrogen adsorption/desorption, Raman spectroscopy, and XRD analyses; TEM and SEM observations. The Brunauer–Emmett–Teller (BET) specific surface area was calculated using the adsorption isotherm in a P / P 0 range of 0.05–0.20.…”

“…The structures of the redox-active materials hybridized within the pores of porous carbons seem to have an effect on the charge/discharge characteristics but cannot be identified by conventional spectroscopic and observation techniques because the amorphous structure of porous carbons hampers the observation of the confined materials, and conductive polymers and redox-active organic compounds consist of light elements. We have reported the existing form of the hybridized polydicyclopentadiene (PDCPD) within the pores of activated carbon (AC) by combining conventional structural characterizations with nitrogen adsorption/desorption and electrochemical measurements . The AC had micropores and mesopores below 4 nm, and PDCPD was not hybridized as a layer nor preferentially localized inside micropores but was uniformly distributed inside both micropores and mesopores as an agglomerate.…”