Rational synthesis of three-dimensional porous ZnCo2O4 film with nanowire walls via simple hydrothermal method

•Hierarchically porous ZnCo2O4 film is prepared via a hydrothermal synthesis method.•Porous ZnCo2O4 film possesses nanowire walls.•ZnCo2O4 film shows high surface area and porosity.

Hierarchical porous semiconductor films are highly desirable for designing high-performance optical and electrochemical devices. Herein, we report a self-supported three-dimensional hierarchical-porous ZnCo2O4 film composed of nanowire walls. The obtained ZnCo2O4 film exhibits a porous architecture with hierarchical porosity from mesoporosity to macroporosity. Additionally, the ZnCo2O4 film is made up of porous walls consisting of interconnected nanowires with diameters of ~85 nm. The as-prepared ZnCo2O4 film also shows a high specific surface area of ~137 m2 g−1 and a noticeable porosity up to 71%. A growth mechanism is proposed. The developed strategy can be extended to the synthesis of other porous binary metal oxide films for applications in solar cells, supercapacitors and batteries.

Graphical-abstractThree-dimensional (3D) porous ZnCo2O4 film with nanowire walls is prepared via a facile hydrothermal method and shows the combined properties of hierarchical porosity and high surface area. Figure optionsDownload full-size imageDownload as PowerPoint slide