Codesigning Alloy Compositions of CdSeyTe1−y Absorbers and MgxZn1−xO Contacts to Increase Solar Cell Efficiency
Abstract
Thin‐film solar cells such as CdTe are a major commercial photovoltaic technology, with more than 25 GW installed worldwide and levelized costs of electricity competitive with fossil fuels. Further progress may result from integrating CdSeyTe1−y absorbers with MgxZn1−xO contacts, but the device efficiency is difficult to maximize due to coupled dependence on chemical composition of both alloys. Herein, a high‐throughput approach is demonstrated to codesign chemical compositions in alloyed MgxZn1−xO/CdSeyTe1−y thin‐film solar cells, using combinatorial libraries of PV devices with orthogonal composition gradients in CdSeyTe1−y absorbers and MgxZn1−xO contacts. It is found that the solar cell performance is a strong and coupled function of both elemental compositions, with efficiency up to 17.7% (VOC = 836 mV, fill factor = 69%, JSC = 30.6 mA cm−2) at atomic compositions of Mg/(Mg + Zn) ≈18% and average Se/(Se + Te) ≈4%. These performance trends among >100 devices are explained by >100 ns lifetime of photoexcited charge carriers at the MgxZn1−xO/CdSeyTe1−y interface where strong Se accumulation is also observed. This study reports the optimal compositions of the commercially relevant MgxZn1−xO/CdSeyTe1−y solar cells and demonstrates a general approach to codesigning performance of alloyed thin‐film solar cells and other optoelectronic devices.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jul 20, 2022
- Source ID
- 10.1002/solr.202200394
Entities
People
- Andriy Zakutayev
- Brian Good
- Craig L. Perkins
- Deborah L. McGott
- Imran S. Khan
- Tursun Ablekim
- Wyatt K. Metzger
Organizations
- Fuel Cell Technologies Office
- National Renewable Energy Laboratory
- Office of Basic Energy Sciences
- Office of Naval Research
- Solar Energy Technologies Office