Professor Xu Yijun, Fuzhou University: new membrane materials can purify water without pressure

Removal of heavy metal ions from water is of great importance to public health, but two-dimensional materials based films usually need pressure driving Recently, Professor Xu Yijun's research group of Fuzhou University reported a dual control strategy for the microstructure and surface properties of two-dimensional titanium carbide based film, which realized the effective removal of various heavy metal ions in water under the condition of no pressure driving Relevant papers were published in nature Sustainability (DOI: 10.1038 / s41893-019-0373-4) recently At present, the problem of water shortage and water pollution in the world is increasingly prominent Water purification is recognized as one of the effective ways to solve the problem of water shortage However, the heavy metal ions in water have the characteristics of high toxicity, high mobility and non biodegradation How to remove the heavy metal ions in water has become an important issue of global concern Because of its high specific surface area and abundant surface functional groups, the two-dimensional material-based film has a broad application prospect in the removal of heavy metal ions in water However, because the two-dimensional materials are easy to stack in the process of film formation, and finally form a dense structure with high density, the resulting membrane materials are usually pressure driven filtration membranes in water purification applications In addition, the two-dimensional membrane materials can only selectively adsorb specific heavy metal ions Under the condition of no pressure driving, it is a challenging task to remove multiple heavy metal ions on a two-dimensional material-based membrane By introducing reduced graphene oxide into the two-dimensional titanium carbide film, Xu Yijun's research group can intercalate and prevent stacking of its nano chips, thus significantly improving the contact area between the membrane materials and heavy metal ions in water On this basis, further surface hydroxylation of two-dimensional titanium carbide based films can not only effectively improve its water wettability, but also enhance the adsorption and reduction of heavy metal ions Under the synergistic effect of microstructure and surface property optimization, the two-dimensional titanium carbide based film has obvious removal effect on a variety of heavy metal cations and heavy metal anions in water In addition, the recovered two-dimensional titanium carbide based films can be recycled for recycling Experts said that this study opened up a new way for the rational use of two-dimensional material-based film and its application in water purification.