Title: Highly Efficient Flexible Hybrid Nanocrystal-Cu(In,Ga)Se-2 (CIGS) Solar Cells
Authors: Liao, Yu-Kuang
Brossard, Mael
Hsieh, Dan-Hua
Lin, Tzu-Neng
Charlton, Martin D. B.
Cheng, Shun-Jen
Chen, Chyong-Hua
Shen, Ji-Lin
Cheng, Lung-Teng
Hsieh, Tung-Po
Lai, Fang-I
Kuo, Shou-Yi
Kuo, Hao-Chung
Savvidis, Pavlos G.
Lagoudakis, Pavlos G.
Department of Electrophysics
Department of Photonics
Keywords: scattering;luminescent down shifting;nanocrystal quantum dots;hybrid photonics
Issue Date: 21-Jan-2015
Abstract: A novel scheme for hybridizing inkjet-printed thin film Cu(In,Ga)Se-2 (CIGS) solar cells with self-assembled clusters of nanocrystal quantum dots (NQDs), which provides a 10.9% relative enhancement of the photon conversion efficiency (PCE), is demonstrated. A non-uniform layer of NQD aggregates is deposited between the transparent conductive oxide and a CdS/CIGS p-n junction using low cost pulsed-spray deposition. Hybridization significantly improves the external quantum efficiency of the hybrid devices in the absorption range of the NQDs and in the red to near-IR parts of the spectrum. The low wavelength response enhancement is found to be induced by luminescent down-shifting (LDS) from the NQD layer, while the increase at longer wavelengths is attributed to internal scattering from NQD aggregates. LDS is demonstrated using time-resolved spectroscopy, and the morphology of the NQD layer is investigated in fluorescence microscopy and cross-sectional transmission electron microscopy. The influence of the NQD dose on the PCE of the hybrid devices is investigated and an optimum value is obtained. The low costs and limited material consumptions associated with pulsed-spray deposition make these flexible hybrid devices promising candidates to help push thin-film photovoltaic technology towards grid parity.
URI: http://dx.doi.org/10.1002/aenm.201401280
ISSN: 1614-6832
DOI: 10.1002/aenm.201401280
Appears in Collections:Articles