01911nas a2200301 4500008004100000022001400041245007100055210006900126260000900195490000700204520095100211653002301162653001801185653002401203653003801227653002601265653002401291100002801315700001601343700002401359700002601383700001601409700001901425700001601444700002401460700001901484856010601503 2023 eng d a1433-785100aChemically gradient hydrogen-bonded organic framework crystal film0 aChemically gradient hydrogenbonded organic framework crystal fil cJUL 0 v623 a

Hydrogen-bonded organic frameworks (HOFs) are ordered supramolecular solid structures, however, nothing much explored as centimetre-scale self-standing films. The fabrication of such crystals comprising self-supported films is challenging due to the limited flexibility and interaction of the crystals, and therefore studies on two-dimensional macrostructures of HOFs are limited to external supports. Herein, we introduce a novel chemical gradient strategy to fabricate a crystal-deposited HOF film on an in situ-formed covalent organic polymer film (Tam-Bdca-CGHOF). The fabricated film showed versatility in chemical bonding along its thickness from covalent to hydrogen-bonded network. The kinetic-controlled Tam-Bdca-CGHOF showed enhanced proton conductivity (8.3x10(-5) S cm(-1)) compared to its rapid kinetic analogue, Tam-Bdca-COP (2.1x10(-5) S cm(-1)), which signifies the advantage of bonding-engineering in the same system.

10aChemical Gradience10aCrystal Films10aFree-Standing Films10ahydrogen-bonded organic framework10aInterfacial Chemistry10aproton conductivity1 aMohammed, Abdul, Khayum1 aRaya, Jesus1 aPandikassala, Ajmal1 aAddicoat, Matthew, A.1 aGaber, Safa1 aAslam, Mohamed1 aAli, Liaqat1 aKurungot, Sreekumar1 aShetty, Dinesh uhttps://library.ncl.res.in/content/chemically-gradient-hydrogen-bonded-organic-framework-crystal-film02307nas a2200265 4500008004100000022001400041245015400055210006900209260000800278300001100286490000700297520133900304653002301643653003301666653002201699653003801721653002401759100001801783700001501801700002401816700002401840700002601864700002001890856013101910 2023 eng d a2352-940700aUnlocking the potential of proton conductivity in guanidinium-based ionic covalent organic nanosheets (iCONs) through pore interior functionalization0 aUnlocking the potential of proton conductivity in guanidiniumbas cAUG a1018660 v333 a

Recently, scientists have been exploring the incorporation of proton carriers such as water and phosphoric acid (PA) into the pores and channels of porous materials to enhance proton conduction performance. Ionic covalent organic nanosheets (iCONs) have been identified as promising functional materials due to their inbuilt ionic interfaces, which can facilitate strong interaction with counter ions present inside the pore structure and thus shorten ion transport pathways. However, there is a lack of research related to proton conductivity in iCONs loaded with PA. To address this, we prepared three functionalized guanidinium-based iCONs using a solvothermal condensation reaction between guanidinium amine (TG) and functionalized terephthaldehyde (Da, Dha, and Dma). PA was also incorporated into the iCON structure via ex situ loading to observe its effects on proton conduction performance. The results showed that both the iCONs and PA-iCONs were highly stable in water, organic solvents, acidic and basic media. Amongst these PA-iCONs, one with hydroxyl-functionalization (PA-DhaTG) displayed high proton conductivity at 90 degrees C and 95% relative humidity due to a Grotthuss mechanism for protons. These functionalized guanidinium-based iCONs could prove useful for applications in energy conversion devices.

10achemical stability10aFunctionalized pore interior10aGuanidinium group10aionic covalent organic nanosheets10aproton conductivity1 aKumar, Sushil1 aHu, Jiahui1 aPandikassala, Ajmal1 aKurungot, Sreekumar1 aAddicoat, Matthew, A.1 aSzekely, Gyorgy uhttps://library.ncl.res.in/content/unlocking-potential-proton-conductivity-guanidinium-based-ionic-covalent-organic-nanosheets