Anhydrous proton conductor consisting of pectin–inorganic composite material

Abstract

An organic-inorganic proton conductive composite material consisting of a biopolymer was prepared by mixing the pectin, tetraethyl titanate, and imidazole. Although the pectin material without the composite dissolved in water, the pectin-inorganic composite material did not show water solubility. In addition, in the composite material, the pectin and imidazole formed an acidbase structure by an electrostatic interaction, and as a result, these composite materials showed a thermal stability at intermediate temperatures (100-2008C). Furthermore, these composite materials indicated the proton conductivity of 5.6 3 10 24 S cm 21 at 1808Cunder anhydrous conditions. The activation energy of the proton conduction under anhydrous conditions was 0.32-0.22 eV and these values were one order of magnitude higher than that of the typical humidified perfluorinated membrane, such as Nafion V R . The organic-inorganic composite material consisting of a biocomponent may have the potential to be utilized as a novel proton conductor under anhydrous conditions.

Imidazole-doped nanocrystalline cellulose solid proton conductor: synthesis, thermal properties, and conductivity

“…This fact explains the difference in activation energies. On the other hand, our results coincide with those obtained for the materials measured at lower humidity levels and/or containing heterocyclic molecules (Kreuer et al 1993;Tang et al 2014;Pandey et al 1999;Yamada et al 2012;Yamada et al 2004;Yamada and Ogino 2015). Generally, the higher activation energy (i.e.…”

Preparation of Gellan Gum-Inorganic Composite Film and Its Metal Ion Accumulation Property

“…The absorption band at ca. 1600 cm −1 , indicating the stretching vibration of the -COO − group [19,23,24], did not show a shift by the addition of GPTMS molecule. These results indicated that the addition of the GPTMS did not affect the -COO − group, which can interact with various metal ions.…”

“…In addition, the organic-inorganic composite materials are prepared by a soft process, such as sol-gel reaction using a silane coupling reagent, and can use various biopolymers, such as proteins, DNA, and polysaccharides, as an organic component [14][15][16]. These biopolymer-inorganic composite materials have been reported for use as an absorbent of harmful compounds [16], sensing materials [17], energy materials [18,19], biomaterials [20], etc. Therefore, composite film consisting of gellan gum and an inorganic component can be expected to be used as a novel environmental material.…”

New liquid-free proton conductive nanocomposite based on imidazole-functionalized cellulose nanofibers

“…Additionally, Nafion is complicated to manufacture and relatively expensive, about 1700 $/m 2 (Bayer et al 2016;Liu et al 2018;Hernández-Flores et al 2016;Mizera et al 2019;Tiwari et al 2016;Wong et al 2019). In the search for new solid polymer electrolytes, an interesting approach is to modify natural polymers (Fujishima et al 2008;Hernández-Flores et al 2016;Jesuraj and Manimuthu 2018;Kalaiselvimary and Prabhu 2018;Kalaiselvimary et al 2019;Połomska et al 2010Połomska et al , 2011Yamada and Goto 2012;Yamada and Ogino 2015), including the most abundant polymer in nature and the main building material of plantscellulose. Many different types of cellulose have investigated in polymeric proton-conducting electrolytes: bacterial cellulose (Gadim et al 2016;Jiang et al 2012;Vilela et al 2020), cellulose whiskers (Xu et al 2019), cellulose nanocrystals (Bano et al 2019;Bayer et al 2016;Ni et al 2016Ni et al , 2018Zhao et al 2019a), and cellulose nanofibers (CNF) (Bayer et al 2016;Di and Yin 2019;Cai et al 2018;Gu et al 2019;Guccini et al 2019;Xu et al 2018;Zhao et al 2019b).…”