In:
Advanced Functional Materials, Wiley, Vol. 30, No. 1 ( 2020-01)
Abstract:
In thin‐film photovoltaic (PV) research and development, it is of interest to determine where the chief losses are occurring within the active layer. Herein, a method is developed and presented by which the spatial distribution of charge collection, operando, is ascertained, and its application in colloidal quantum dot (CQD) solar cells is demonstrated at a wide range of relevant bias conditions. A systematic computational method that relies only on knowledge of measured optical parameters and bias‐dependent external quantum efficiency spectra is implemented. It is found that, in CQD PV devices, the region near the thiol‐treated hole‐transport layer suffers from low collection efficiency, as a result of bad band alignment at this interface. The active layer is not fully depleted at short‐circuit conditions, and this accounts for the limited short‐circuit current of these CQD solar cells. The high collection efficiency outside of the depleted region agrees with a diffusion length on the order of hundreds of nanometers. The method provides a quantitative tool to study the operating principles and the physical origins of losses in CQD solar cells, and can be deployed in thin‐film solar cell device architectures based on perovskites, organics, CQDs, and combinations of these materials.
Type of Medium:
Online Resource
ISSN:
1616-301X
,
1616-3028
DOI:
10.1002/adfm.201908200
Language:
English
Publisher:
Wiley
Publication Date:
2020
detail.hit.zdb_id:
2029061-5
detail.hit.zdb_id:
2039420-2
SSG:
11
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