基于聚多巴胺改性的木海绵/MOFs复合材料的制备及其吸附性能研究

Preparation of Wood Sponge/MOFs Composites Based on Polydopamine Modification and Study of Their Adsorption Properties

经济发展过程中产生的环境污染已对生态环境和人类健康构成严重威胁。在众多材料中,金属有机骨架(MOFs)因其出色的吸附性能在污染物处理领域展现出巨大的潜力。然而,MOFs的刚性结构和粉末形态极大地限制了其实际应用范围。因此,寻找一种合适的载体以拓宽MOFs的应用途径显得尤为重要。随着全球资源日益紧张,可再生绿色纤维素材料受到了广泛关注。木海绵(WS)作为一种新型环保材料,以其独特的层级、管状多孔结构,高孔隙率和大比表面积等优点脱颖而出。这些特性使得WS成为MOFs的理想载体,两者的结合有望实现对有机污染物的高效吸附。针对MOFs机械强度弱、对有机污染物吸附容量低的问题,论文设计制备了一种ZIF-8@PWS的复合材料。首先利用多巴胺仿生矿化WS,得到表面覆盖有聚多巴胺的木海绵(PWS),随后在PWS表面生长沸石咪唑酯骨架(ZIF-8),形成ZIF-8@PWS复合材料。复合材料对亚甲基蓝(MB)的吸附容量可在180 min内达到151.3 mg/g,具有良好的吸附性能。

The escalating environmental pollution resulting from economic growth poses a significant threat to both the ecological balance and human health.Among a group of materials,metal-organic skeletons(MOFs)have a broad prospect in the field of pollutant adsorption.However,the rigid structure and powder morphology of MOFs severely limit their applications,so it is necessary to find a suitable carrier to broaden the application pathway of MOFs.As the global non-renewable resources are getting less and less,renewable green cellulose is gradually coming into the public's attention.Wood sponge(WS)with hierarchical and tubular porosity is a new type of environmentally friendly material developed in recent years,which has the advantages of high porosity and large specific surface area,and the composite of MOFs and WS is expected to achieve high-capacity adsorption of organic pollutants.In this paper,a composite material of ZIF-8@PWS was designed to address the problems of weak mechanical strength of MOFs and low adsorption capacity of organic pollutants.Firstly,WS was biomimetically mineralised using dopamine to obtain a wood sponge(PWS)covered with dopamine on the surface,followed by the growth of zeolite imidazolium ester skeleton(ZIF-8)on the surface of PWS.The adsorption capacity of the composite material for MB could reach 151.3 mg/g in 180 min,which has good adsorption performance.