TY - JOUR
T1 - Hybrid perovskite solar cells: In situ investigation of solution-processed PbI2 reveals metastable precursors and a pathway to producing porous thin films
AU - Barrit, Dounya
AU - Sheikh, Arif D.
AU - Munir, Rahim
AU - Barbe, Jeremy
AU - Li, Ruipeng
AU - Smilgies, Detlef-M.
AU - Amassian, Aram
N1 - KAUST Repository Item: Exported on 2020-10-01
Acknowledgements: This work was supported by the King Abdullah University of Science and Technology (KAUST). CHESS is supported by the NSF & NIH/NIGMS via NSF award DMR-1332208.
PY - 2017/4/17
Y1 - 2017/4/17
N2 - The successful and widely used two-step process of producing the hybrid organic-inorganic perovskite CH3NH3PbI3, consists of converting a solution deposited PbI2 film by reacting it with CH3NH3I. Here, we investigate the solidification of PbI2 films from a DMF solution by performing in situ grazing incidence wide angle X-ray scattering (GIWAXS) measurements. The measurements reveal an elaborate sol–gel process involving three PbI2⋅DMF solvate complexes—including disordered and ordered ones—prior to PbI2 formation. The ordered solvates appear to be metastable as they transform into the PbI2 phase in air within minutes without annealing. Morphological analysis of air-dried and annealed films reveals that the air-dried PbI2 is substantially more porous when the coating process produces one of the intermediate solvates, making this more suitable for subsequent conversion into the perovskite phase. The observation of metastable solvates on the pathway to PbI2 formation open up new opportunities for influencing the two-step conversion of metal halides into efficient light harvesting or emitting perovskite semiconductors.
AB - The successful and widely used two-step process of producing the hybrid organic-inorganic perovskite CH3NH3PbI3, consists of converting a solution deposited PbI2 film by reacting it with CH3NH3I. Here, we investigate the solidification of PbI2 films from a DMF solution by performing in situ grazing incidence wide angle X-ray scattering (GIWAXS) measurements. The measurements reveal an elaborate sol–gel process involving three PbI2⋅DMF solvate complexes—including disordered and ordered ones—prior to PbI2 formation. The ordered solvates appear to be metastable as they transform into the PbI2 phase in air within minutes without annealing. Morphological analysis of air-dried and annealed films reveals that the air-dried PbI2 is substantially more porous when the coating process produces one of the intermediate solvates, making this more suitable for subsequent conversion into the perovskite phase. The observation of metastable solvates on the pathway to PbI2 formation open up new opportunities for influencing the two-step conversion of metal halides into efficient light harvesting or emitting perovskite semiconductors.
UR - http://hdl.handle.net/10754/623438
UR - https://www.cambridge.org/core/journals/journal-of-materials-research/article/hybrid-perovskite-solar-cells-in-situ-investigation-of-solutionprocessed-pbi2-reveals-metastable-precursors-and-a-pathway-to-producing-porous-thin-films/1B173FB59801ED8CE7D66F9216B29829
UR - http://www.scopus.com/inward/record.url?scp=85017513761&partnerID=8YFLogxK
U2 - 10.1557/jmr.2017.117
DO - 10.1557/jmr.2017.117
M3 - Article
SN - 0884-2914
VL - 32
SP - 1899
EP - 1907
JO - Journal of Materials Research
JF - Journal of Materials Research
IS - 10
ER -