Dual‐Absorber Thin‐Film Solar Cell: A High‐Efficiency Design

The solar cell device architecture is critical for photovoltaic action and achieving high efficiency. Herein, a dual‐absorber solar cell is demonstrated where a stack of two band‐aligned absorbers with different bandgaps facilitates absorption of a broader range of the solar spectrum resulting in higher short‐circuit current. This dual‐absorber design is analyzed and a narrow range of optimal parameters which can achieve net efficiency gain is summarized. By introducing an additional absorber–absorber interface, the interfacial defect and band offset become essential parameters for the efficient functioning of a dual‐absorber device. Single‐, double‐, and triple‐absorber configurations, their performance enhancement, and synergetic spectrum utilization are compared. The proposed dual‐absorber design is more straightforward and has comparable performance to a tandem device, thus presenting a potentially cost‐effective solar cells design.