Guan Li Zhi, Patiño Julian, Cuadrado-Collados Carlos, Tamayo Aitana, Gutiérrez María C, Ferrer M Luisa, Silvestre-Albero Joaquín, Del Monte Francisco
Laboratorio de Materiales Avanzados, Departamento de Química Inorgánica-Instituto Universitario de Materiales , Universidad de Alicante , Ctra. San Vicente-Alicante s/n , E-03690 San Vicente del Raspeig , Spain.
ACS Appl Mater Interfaces. 2019 Jul 10;11(27):24493-24503. doi: 10.1021/acsami.9b02745. Epub 2019 Jun 27.
The elimination of small amounts of water from alcohols is by no means a trivial issue in many practical applications like, for instance, the dehumidification of biocombustibles. The use of carbonaceous materials as sorbents has been far less explored than that of other materials because their hydrophobic character has typically limited their water uptake. Herein, we designed a synthetic process based on the use of eutectic mixtures that allowed the homogeneous dispersion of graphene oxide (GO) in the liquid containing the carbon precursor, e.g., furfuryl alcohol. Thus, after polymerization and a subsequent carbonization process, we were able to obtain porous carbon-GO composites where the combination of pore diameter and surface hydrophilicity provided a remarkable capacity for water uptake but extremely low methanol and ethanol uptake along the entire range of relative pressures evaluated in this work. Both the neat water uptake and the uptake difference between water and either methanol or ethanol of our carbon-GO composites were similar or eventually better than the uptake previously reported for other materials, also exhibiting preferential water-to-alcohol adsorption, e.g., porous coordination polymers, metal-organic frameworks, polyoxometalates, and covalent two-dimensional nanosheets embedded in a polymer matrix. Moreover, water versus alcohol uptake was particularly remarkable at low partial pressures in our carbon-GO composites.
在许多实际应用中，如生物燃料的除湿，从醇类中去除少量水分绝不是一个小问题。与其他材料相比，碳质材料作为吸附剂的应用研究较少，因为其疏水性通常限制了它们对水的吸收。在此，我们设计了一种基于使用低共熔混合物的合成工艺，该工艺可使氧化石墨烯（GO）均匀分散在含有碳前驱体（如糠醇）的液体中。因此，经过聚合和随后的碳化过程，我们能够获得多孔碳-GO复合材料，其中孔径和表面亲水性的结合提供了显著的吸水能力，但在本工作评估的整个相对压力范围内，对甲醇和乙醇的吸收极低。我们的碳-GO复合材料的纯水吸收以及水与甲醇或乙醇之间的吸收差异与之前报道的其他材料相似，甚至最终更好，同时也表现出优先的水对醇的吸附，例如多孔配位聚合物、金属有机框架、多金属氧酸盐以及嵌入聚合物基质中的共价二维纳米片。此外，在我们的碳-GO复合材料中，在低分压下，水与醇的吸收差异尤为显著。
