ZnO is a promising electron transport material. It has not only similar energy level position and physical properties to traditional TiO₂, but also excellent light transmittance, conductivity, stability, low cost and low temperature preparation. Studies have shown that the one-dimensional nanostructured electron transport layer has a higher electron transport rate, provides a direct electron transport channel and avoids its being recombined at the grain boundaries, thereby improving carrier collection efficiency. It has also been reported that the electron transport rate of ZnO nanorods is significantly better than that of TiO₂, showing their great potential applications. In perovskite solar cells, the verticality of ZnO nanorods is a key factor affecting device efficiency. The AZO (ZnO∶Al) glass, as an inexpensive transparent conductive substrate, is expected to obtain the best verticality because it has no lattice mismatch with ZnO nanorods. And in the field of perovskite solar cells, the light absorbing layer is usually prepared in a glove box and it has obviously not been industralized. However, there are few reports about perovskite solar cells prepared in atmospheric environment with AZO as substrate and ZnO nanorods as electron transport layer. And it is still much less efficient than the current perovskite solar cells with TiO₂ as the electronic transport layer. It can be seen that further improving the efficiency of the structural battery prepared in the atmospheric environment is an urgent problem to be solved. In this paper, ZnO nanorods are prepared as an electron transport layer by the hydrothermal method. The effects of hydrothermal temperature, the number of seed layer, the precursor concentration, the substrate type, the hydrothermal time, and the other process parameters on the morphology and crystalline properties of ZnO nanorods are systematically studied, and the growth mechanism is analyzed. The results show that the length of the nanorods is mainly controlled by the hydrothermal time and hydrothermal temperature, and that the radial size is mainly determined by the number of seed layers and the concentration of the precursor solution. And the results also indicate that the verticality of ZnO nanorods’ growth is closely related to the substrate, and that the ZnO nanorods on the AZO substrate have the best growth verticality. On this basis, the perovskite solar cell is prepared in the atmospheric environment, and the optimal efficiency of the photovoltaic device prepared with AZO substrate increases from 7.0% reported in the literature to 9.63%. This is of great significance for enriching the design ideas of perovskite solar cells and further reducing costs.