Hierarchical SnO₂ nanocrystallites aggregates (NAs) were prepared with a simple room temperature⁻based aqueous solution method followed by simple freeze-drying treatment. The as-prepared SnO₂ NAs were subsequently combined with SnO₂ nanosheet⁻based structures from the viewpoint of a function-matching strategy, and under an optimized condition, a power conversion efficiency (PCE) of 5.59% was obtained for the resultant hybrid photoanode, a remarkable 60% enhancement compared to that of dye-sensitized solar cells (DSCs) fabricated with bare SnO₂ NAs architecture. The significantly enhanced efficiency can be attributed to the combination of the desirable electron transport property obtained by the intentionally introduced SnO₂ nanosheets (NSs) and the effectively retained inherent characteristics of SnO₂ NAs, i.e., large surface area and strong light-scattering effect. This work provides a promising approach for the rapid development of highly efficient SnO₂ photoanode film-based DSCs with the properties of simplicity of operation and control over the photoanode composition.
Keywords: SnO2 aggregate/nanosheet composite; dye-sensitized solar cells; hierarchical SnO2 aggregates; photoanode; room temperature method.