TY - JOUR

T1 - Structure and Properties of a Nanoporous Supercapacitor

AU - Fayon, P.

AU - Thomas, J. M. H.

AU - Trewin, A.

PY - 2016/11/17

Y1 - 2016/11/17

N2 - In this paper we have shown through the use of simulated synthesis that the structure of Aza-CMP is an amorphous interpenetrated network. We also show that structural differences, including the nanoporosity, found for Aza-CMP synthesized at different temperatures are due to the differences in melting points and hence miscibility of the reactants. Network bonding errors leave unreacted carbonyl and amine groups that introduce regions of higher network charge and thus are highly favorable binding sites for electrolyte ions. Binding of the electrolyte ions is favorable whether the system is charged or neutral meaning that uptake of electrolyte ions before application of a voltage bias is highly likely. We show that the SO42- electrolyte ion is restricted to the mesoporous regions due to its larger size. In mesoporous and microporous models, SO42- ion diffusion is slow and tortuous, with the possibility that the SO42- ion becomes trapped in pore dead ends. This suggests that the charging mechanism in Aza-CMP supercapacitor electrodes is likely to be dominated by movement of H3O+ electrolyte ions through the nanoporous structure.

AB - In this paper we have shown through the use of simulated synthesis that the structure of Aza-CMP is an amorphous interpenetrated network. We also show that structural differences, including the nanoporosity, found for Aza-CMP synthesized at different temperatures are due to the differences in melting points and hence miscibility of the reactants. Network bonding errors leave unreacted carbonyl and amine groups that introduce regions of higher network charge and thus are highly favorable binding sites for electrolyte ions. Binding of the electrolyte ions is favorable whether the system is charged or neutral meaning that uptake of electrolyte ions before application of a voltage bias is highly likely. We show that the SO42- electrolyte ion is restricted to the mesoporous regions due to its larger size. In mesoporous and microporous models, SO42- ion diffusion is slow and tortuous, with the possibility that the SO42- ion becomes trapped in pore dead ends. This suggests that the charging mechanism in Aza-CMP supercapacitor electrodes is likely to be dominated by movement of H3O+ electrolyte ions through the nanoporous structure.

KW - MOLECULAR-DYNAMICS SIMULATIONS

KW - MICROPOROUS POLYMER NETWORKS

KW - GRAPHICS PROCESSING UNITS

KW - SURFACE-AREA

KW - CARBON

KW - CAPACITANCE

KW - STORAGE

U2 - 10.1021/acs.jpcc.6b08712

DO - 10.1021/acs.jpcc.6b08712

M3 - Journal article

VL - 120

SP - 25880

EP - 25891

JO - The Journal of Physical Chemistry C

JF - The Journal of Physical Chemistry C

SN - 1932-7447

IS - 45

ER -