Confinement of poly(allylamine) in Preyssler-type polyoxometalate and potassium ion framework for enhanced proton conductivity
Confinement of poly(allylamine) in Preyssler-type polyoxometalate and potassium ion framework for enhanced proton conductivity
复制标题
DOI：
10.1038/s42004-019-0111-x
复制
发表时间：
2019-01-25
影响因子：
5.9
通讯作者：
Uchida, Sayaka
中科院分区：
文献类型：
--
作者：
Iwano, Tsukasa;Miyazawa, Satoru;Uchida, Sayaka
多金属酸氧基固体是极有前途的质子导电固体电解质。在这项工作中，preyssler型多金属氧酸盐与钾离子和聚丙烯胺（也是一种良好的质子导体）从水溶液中结晶。本研究表明，聚金属氧酸盐和聚烯丙胺的吸湿性引起的低耐久性可以通过固态的聚金属氧酸盐和质子化胺部分之间的静电相互作用来规避。用不同平均分子量的聚烯丙胺合成结晶化合物，在温湿和低温条件下，所有化合物的质子电导率均达到10(-2)S cm（-1）。光谱研究表明，聚烯丙胺的侧链迁移率和氢键网络重排分别有助于低平均分子量和高平均分子量聚烯丙胺化合物的质子传导。虽然以前已经报道了许多质子导电的非晶多金属氧酸-聚合物复合材料，但这些结果显示了晶体复合材料的结构-性能关系和高功能。
Polyoxometalate based solids are promising candidates of proton-conducting solid electrolytes. In this work, a Preyssler-type polyoxometalate is crystallized with potassium ions and poly(allylamine), which is also a good proton conductor, from aqueous solutions. Here we show that the hygroscopicity induced low durability of polyoxometalate and poly(allylamine) can be circumvented by the electrostatic interaction between the polyoxometalate and protonated amine moieties in the solid state. Crystalline compounds are synthesized with poly(allylamine) of different average molecular weights, and all compounds achieve proton conductivities of 10(-2) S cm(-1) under mild-humidity and low-temperature conditions. Spectroscopic studies reveal that the side-chain mobility of poly(allylamine) and hydrogen-bonding network rearrangement contribute to the proton conduction of compounds with poly(allylamine) of low and high average molecular weights, respectively. While numbers of proton-conducting amorphous polyoxometalate-polymer composites are reported previously, these results show both structure-property relationship and high functionality in crystalline composites.