Efficiency Enhancement of InGaN-Based Multiple Quantum Well Solar Cells Employing Antireflective ZnO Nanorod Arrays

Antireflective ZnO nanorod arrays (NRAs) by a scalable chemical method have been applied for InGaN-based multiple quantum well solar cells. The length of the NRAs plays an important role in photovoltaic characteristics. It was found that the 1.1-μm-long NRA results in enhanced conversion efficiency due to the suppressed surface reflection. However, the 2.5- μm-long NRAs, although exhibiting the lowest reflection, lead to slightly deteriorated performances, possibly due to the increased absorption of the NRAs. The results indicate that the absorption of lengthened NRAs should be considered when optimizing their antireflection performances. We demonstrated a viable efficiency-boosting way for photovoltaics.