Photonic effect of a central ultrathin metal film on the performance of series and parallel homo-tandem solar cells

Abstract

We compare the performances of single cells, parallel and series homo-tandem solar cells by focusing on the effect of a central ultra thin metal film acting as an interconnecting layer in the series case or as an electrode in the parallel case. Cells with this metal film are found to outperform classic solar cells thanks to better interference management. Moreover, we find that photonic optimization from an absorption point of view can be accompanied by a reduction of the total amount of active material. We show that the best types of cell strongly depends on the maximum allowed active material thickness to ensure good carrier collection. We also compare ITO and a recently devised ITO-free alternative, the Two-Resonance Tapping Cavity, as transparent electrode and we show how this choice influences

Parallel Planar Heterojunction Strategy Enables Sb2S3 Solar Cells with Efficiency Exceeding 8 %

“…[11,12] Unfortunately, there is no report on solution-processed parallel solar cells, which is very likely related to the complexity in designing terminal electrodes and/or interfacial block layers in parallel tandem systems. [13,14] Antimony trisulfide (Sb 2 S 3 ) consists of non-toxic and earth-abundant elements and is a promising photovoltaic photon-harvesting material [15] due to its large light absorption coefficient (α � 10 5 cm À 1 ) in the visible spectral range, a suitable band gap (E g = 1.4-1.8 eV), and high electron (μ e � 10 cm 2 V À 1 s À 1 ) [16] and hole (μ h � 2.6 cm 2 V À 1 s À 1 ) [17] mobility. Theoretically, an Sb 2 S 3 single-junction solar cell can deliver a power conversion efficiency (η) of 27-33 %.…”

“…Due to the critical crystallization temperature of inorganic semiconductors, solution‐processed tandem PHJ method has been rarely utilized for inorganic/inorganic systems, such as Sb 2 Se 3 /Sb 2 S 3 and Sb 2 S 3 /Si tandem solar cells [11,12] . Unfortunately, there is no report on solution‐processed parallel solar cells, which is very likely related to the complexity in designing terminal electrodes and/or interfacial block layers in parallel tandem systems [13,14] …”