Phenolic-metal complexation coatings have been discovered to be a universal route for the deposition of multifunctional coatings. However, most complexation coatings have been prepared by the immersion method, which limits their practical large-scale application. Herein, we describe a facile and green engineering strategy that involves spraying phenolic compound and metal ions on substrate to form in-situ complexation coating with different coordination states. The coating is formed within minutes and it can be achieved in large scale by the spray method. The pyrogallol-Fe^III complexation coating is prepared at pH 7.5, which consists predominantly of biscoordination complexation with a small amount of tris-coordination complexation. It displays that the water contact angle is near zero due to the generation of rough hierarchical structures and massive hydroxyl groups. The superhydrophilic cotton resulting from the deposition of the pyrogallol-Fe^III complexation can separate oil/water mixtures and surfactant-stabilized oil-in-water emulsions with high separation efficiency. The formation of the phenolic-metal complexation coating by using spray technique constitutes a cost-effective and environmentally friendly, strategy with potential to be applied for large-scale surface engineering processes and green oil/water separation.

现已发现，酚醛金属络合涂层是多功能涂层沉积的通用途径。然而，大多数络合涂料是通过浸没法制备的，这限制了它们的实际大规模应用。在本文中，我们描述了一种简便而绿色的工程策略，其中涉及在基材上喷涂酚类化合物和金属离子以形成具有不同配位态的原位络合涂层。涂层可在数分钟内形成，并且可以通过喷涂方法大规模实现。邻苯三酚-Fe ^III在pH 7.5下制备络合涂层，该涂层主要由双配位络合和少量的tris-配位络合组成。结果表明，由于粗糙的分层结构和大量的羟基的生成，水的接触角接近于零。邻苯三酚-Fe ^III络合物沉积产生的超亲水棉可以高分离效率分离油/水混合物和表面活性剂稳定的水包油乳液。通过喷涂技术形成酚醛金属络合涂层构成了一种具有成本效益且对环境友好的策略，有望应用于大规模表面工程工艺和绿色油水分离。