Du Jiarui, Yu Guangli, Lin Huiming, Jie Pengfei, Zhang Feng, Qu Fengyu, Wen Chen, Feng Lei, Liang Xiaoqiang
Key Laboratory of Photochemical Biomaterials and Energy Storage Materials, Heilongjiang Province and College of Chemistry and Chemical Engineering, Harbin Normal University, Harbin 150025, PR China.
Key Laboratory of Polyoxometalate Science of Ministry of Education Institution, Northeast Normal University, Changchun 130024, PR China.
J Colloid Interface Sci. 2020 Aug 1;573:360-369. doi: 10.1016/j.jcis.2020.04.023. Epub 2020 Apr 7.
A series of composites have been fabricated by introducing ionic liquid (IL) (ship) into chromium terephthalate MIL-101 (bottle) by ship-in-bottle method (IL@MIL-101s), the resulting IL@MIL-101s are endowed to high water retention, which is essential to proton conducting on multiple energy-involved applications at the low relative humidity (RH). The humidifying IL can lower water loss and increase water uptake, and thus improves water retention properties of the composites aided by the mesoporous MIL-101 at low RH. The hydropenic proton transfer pathways are modeled inside MOF and between IL-MOF, diminishing energy barrier routes for proton hopping, and thus a promotive proton transfer is rendered via Grotthuss mechanism. Specially, the IL@MIL-101 (SIB-3) unfolds a high proton conductivity (σ = 4.4 × 10 S cm) at RH as low as ~23%, five orders of magnitude increase than that of parent MIL-101 (1.1 × 10 S cm) at 323 K. Besides, IL@MIL-101s as fillers are incorporated into polymer blends to form hybrid membranes, appearing the relatively high proton conductivity (4.3 × 10 S cm) under ~23% RH at 323 K.
通过瓶中造船法（离子液体@MIL-101s）将离子液体（IL）（船）引入对苯二甲酸铬MIL-101（瓶）中制备了一系列复合材料，所得离子液体@MIL-101s具有高保水性，这对于在低相对湿度（RH）下涉及多种能量的应用中的质子传导至关重要。加湿的离子液体可以减少水分流失并增加水分吸收，从而在低RH条件下借助介孔MIL-101提高复合材料的保水性能。在金属有机框架（MOF）内部以及离子液体-金属有机框架之间对亲水性质子转移途径进行了建模，减少了质子跳跃的能垒路径，从而通过格罗特斯机制实现了促进质子转移。特别地，离子液体@MIL-101（SIB-3）在低至约23%的RH下展现出高质子电导率（σ = 4.4×10 S cm），在323 K时比母体MIL-101（1.1×10 S cm）高五个数量级。此外，离子液体@MIL-101s作为填料被掺入聚合物共混物中形成混合膜，并在323 K、约23%的RH下表现出相对较高的质子电导率（4.3×10 S cm）。
