Facile synthesis of three dimensional porous ZnO films with mesoporous walls and gas sensing properties

Controllable synthesis of 3-D mesoporous ZnO films is highly desirable for gas sensor application. Herein, we report a facile preparation of 3-D mesoporous ZnO film on Ag interdigitated electrodes substrate. The as-prepared ZnO film has a mesoporous walls ranging from 2–5 nm, as revealed by XRD, SEM, and TEM. Importantly, the as-prepared 3-D ZnO film shows an excellent ethanol gas sensing. - Graphical abstract: The detailed electron microscopy studies indicated that the as grown ZnO nanowalls exhibited a mesoporous structure composed of numerous tiny single crystals nanoparticles with an average size of 5 nm. One important issue for the application of the porous material was the specific surface area. - Highlights: • Novel three dimensional porous ZnO films with mesoporous walls were synthesized via a facile solution method. • The mesoporous ZnO nanowalls showed a high sensitivity (36.67) to 200 ppm ethanol at 285 °C. • The reason of their superior response time and changing amplitude was discussed.