Surface-Activated Corrosion in Tin-Lead Halide Perovskite Solar Cells

Journal Article · Tue Sep 29 04:00:00 EDT 2020 · ACS Energy Letters

DOI:https://doi.org/10.1021/acsenergylett.0c01445· OSTI ID:1762455

Mundt, Laura E.; Tong, Jinhui; Palmstrom, Axel F.; Dunfield, Sean P.; Zhu, Kai; Berry, Joseph J.; Schelhas, Laura T.; Ratcliff, Erin L.

Mixed tin–lead halide perovskite solar cells have promising power conversion efficiencies, but long-term stability is still a challenge. Herein we examine the stability of a 60:40 tin–lead perovskite to better understand diminished device performance upon thermal treatment, both in ambient and inert atmosphere. Operando X-ray diffraction shows a stable bulk structure of the perovskite absorber, leading to the hypothesis that surface chemistry dominates the degradation mechanism. X-ray photoelectron spectroscopy reveals two new observations post-thermal annealing that accompany previously reported Sn4+ evolution: (i) the formation of I3– intermediates preceding I2 loss at the surface and (ii) evidence of under-coordinated tin and lead surface sites (Snd<2+ and Pbd<2+, respectively) in inert and ambient conditions. These two species indicate an activated corrosion (i.e., both oxidation and reduction) process at the surface as a possible chemical pathway for degradation, which is expected to be accelerated under operando voltage and light biases.

• Research Organization: National Renewable Energy Laboratory (NREL), Golden, CO (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Solar Energy Technologies Office (EE-4S)
• DOE Contract Number: AC36-08GO28308
• OSTI ID: 1762455
• Report Number(s): NREL/JA-5900-78853; MainId:32770; UUID:38af78c8-33be-418f-8ad6-e57d02be965e; MainAdminID:19165
• Journal Information: ACS Energy Letters, Journal Name: ACS Energy Letters Journal Issue: 11 Vol. 5
• Country of Publication: United States
• Language: English

Related Subjects

41 EE - Solar Energy Technologies Office (EE-4S)
X-ray photoelectron spectroscopy
corrosion
degradation
lead compounds
lead metallography
perovskite
photodegradation
surface chemistry
tin compounds
tin metallography