Crystalline hydrates of calix[4]arene-para-sulfonic acid with n (n = 6–16) water molecules: a structure modeling

Supramolecular Calix[n]arenes-Intercalated Graphene Oxide Membranes for Efficient Proton Conduction

“…Previous investigations have found that SC[n]A exhibited high proton conductivity up to 10 −1 S cm −1 at room temperature, 80%−85% RH, 39,40 close to or even higher than that of heteropolyacids H 3 PW 12 O 40 •xH 2 O or Nafion, 41,42 and increased in the order of SC [4]A < SC [6]A < SC [8]A. 37,43 Thus, SC[n]As hold great promise in incorporating sufficient proton donors within GO nanosheets, while firmly supporting adjacent GO nanosheets with less space occupancy.…”

“…It can thus be speculated that intercalators with high theoretical IEC w and rigid framework structure are highly desired, because they can synergistically optimize chemical microenvironment and physical microenvironment for proton transport. 32 p-Sulfonato calix[n]arenes (p-SC[n]A, n = 4−8), an emerging family of hydrophilic supramolecular substances, have been extensively explored in molecular or ionic recognition and sensing, enzyme assays, and biological/medical chemistry et al 33−36 From the standpoint of proton conductivity, SC[n]A should be a preferred choice owing to its unique properties: a rigid fragment of an organic core, layers comprised of proton donors (−SO 3 H) that was surrounded by a large amount of bound water molecules, 37,38 an ultrahigh theoretical ion exchange capacity (IEC w ) of 5.37 mmol g −1 and easy modifiability. Previous investigations have found that SC[n]A exhibited high proton conductivity up to 10 −1 S cm −1 at room temperature, 80%−85% RH, 39,40 close to or even higher than that of heteropolyacids H 3 PW 12 O 40 •xH 2 O or Nafion, 41,42 and increased in the order of SC [4]A < SC [6]A < SC [8]A.…”

“…p -Sulfonato calix­[ n ]­arenes ( p -SC­[ n ]­A, n = 4–8), an emerging family of hydrophilic supramolecular substances, have been extensively explored in molecular or ionic recognition and sensing, enzyme assays, and biological/medical chemistry et al − From the standpoint of proton conductivity, SC­[ n ]­A should be a preferred choice owing to its unique properties: a rigid fragment of an organic core, layers comprised of proton donors (−SO 3 H) that was surrounded by a large amount of bound water molecules, , an ultrahigh theoretical ion exchange capacity (IEC w ) of 5.37 mmol g –1 and easy modifiability. Previous investigations have found that SC­[ n ]­A exhibited high proton conductivity up to 10 –1 S cm –1 at room temperature, 80%–85% RH, , close to or even higher than that of heteropolyacids H 3 PW 12 O 40 · x H 2 O or Nafion, , and increased in the order of SC[4]­A < SC[6]­A < SC[8]­A. , Thus, SC­[ n ]As hold great promise in incorporating sufficient proton donors within GO nanosheets, while firmly supporting adjacent GO nanosheets with less space occupancy.…”