Zn^(2+)-Ni^(2+)-Al^(3+)-类水滑石@Al薄膜制备及其光催化性能

Preparation of Zn^(2+)-Ni^(2+)-Al^(3+)-LDHs@Al thin films and its photocatalytic properties

含过渡金属元素的类水滑石(LDHs)材料在可见光催化领域显示了广泛应用前景.然而LDHs粉末在催化反应中难回收、易流失,不利于材料的循环利用.以铝板为基体,通过原位生长技术在基体表面原位生长Zn^(2+)-Ni^(2+)-Al^(3+)-LDHs,开辟制备Zn^(2+)-Ni^(2+)-Al^(3+)-LDHs@Al材料的新方法.研究表明,Zn^(2+)-Ni^(2+)-Al^(3+)LDHs薄膜在铝基底纵向生长,具有高取向性.LDHs结晶度较高,片层结构规整,极大暴露了LDHs催化活性较高的层板边缘.该薄膜材料具有较低禁带宽度、较高可见光催化活性.Zn^(2+)-Ni^(2+)-Al^(3+)-LDHs@Al能够有效降解甲基橙(MO)有机染料废水,多次循环后对染料的降解率可达98%.该材料极大的增强了对光的利用率,促进了光生电子和空穴对的分离和转移,提高了材料光催化活性,推动和强化了LDHs材料的循环利用及综合处理废水的能力,提高了其应用价值和应用范围,为LDHs材料的开发、设计及应用提供了新思路.

Transition metal-containing LDHs have shown broad application prospects in the field of visible light catalysis.However,LDHs powder is difficult to reused and easy to lose in the catalytic reaction,which hinders the recycling of materials.In this paper,Zn^(2+)-Ni^(2+)-Al^(3+)-LDHs was grown in situ on the surface of the substrate by in-situ growth technology,and a new method for preparing Zn^(2+)-Ni^(2+)-Al^(3+)-LDHs@Al materials was developed.The research shows that the Zn^(2+)-Ni^(2+)-Al^(3+)-LDHs thin film grows longitudinally on the aluminum substrate and has high orientation.LDHs have high crystallinity and regular lamellar structure,which greatly exposes the edges of the lamellae with high catalytic activity of LDHs.The thin film material has low band gap width,and high visible light catalytic activity.Photocatalytic performance studies show that Zn^(2+)-Ni^(2+)-Al^(3+)-LDHs@Al can effectively degrade MO dye wastewater,and the degradation rate of dyes can reach 98%after multiple cycles.'The photocatalytic mechanism study shows that the material greatly enhances the utilization of light,promotes the separation and transfer of photo-generated electron and hole pairs,improves the photocatalytic activity of the material,and promotes and strengthens the recycling and synthesis of hydrotalcite-like materials.The ability to treat wastewater improves its application value and application range,and provides new ideas for the development,design and application of LDHs materials.