In-Situ Hydrothermal Growth of Bi-Hierarchical ZnO Nanoarchitecture with Surface Modification for Efficient Hybrid Solar Cells

Abstract The ability to fabricate hierarchical one-dimensional (1D) ZnO nanoarchitecture with a high degree of multifunctionalities by suitable synthetic strategies still represents a vital issue towards boosting the ultimate photoelectric conversion efficiency of organic-inorganic hybrid solar cells (HSCs). We herein synthesize a hierarchical 1D ZnO nanoarchitecture i.e. ZnO NAR/NR grown on a dual-dimension seeded layer via an all-solution chemical bath deposition process. It is found that ZnO NAR/NR nanoarchitecture can accelerate electron separation and the D205 dye uptake, and hence simultaneously maximizing the key features of photoelectrode in HSCs i.e. carrier generation and charge transport. A remarkable efficiency of 1.30% is achieved under 1 sun illumination for D205-modified hierarchical ZnO HSC fabricated with a very thin layer of ZnO NAR/NR (thickness ∼1 μm) and a significant improvement is evaluated with respect to a reference photoanode made from ZnO nanorods.