The organic-inorganic perovskite films CH3N-H3PbI3 were synthesized from solutions with different ratios of initial reagents (PbI2 to CH3NH3I were taken in the ratio 1:1, 1:2 and 1:3). To deposit films of organic-inorganic perovskite, solutions with different ratio of initial reagents were applied to the substrates by the spin-coating method. The organic-inorganic perovskites synthesized were of one chemical composition in spite of the fact that different chemical reactions proceeded during the synthesis. It was found that the formation of perovskite occurs according to different schemes depending on the ra-tio of PbI2 and CH3NH3I: without the formation of intermediate compounds (at ratio 1:1) and with the formation of one (CH3NH3)2PbI4 (1:2) and two intermediate compounds (CH3NH3)3PbI5, (CH3NH3)2PbI4 (1:3).
It was established that regardless of the ratio of the initial reagents, organic-inorganic perovskites with different morphology are formed. At the ratio of the initial reagents 1:1, needle particles formed, and at the ratio of 1:2 and 1:3, particles have the form of a maple leaf and round shape, respectively.
To improve the film stability, polyvinyl butyral polymer was used. It is an amorphous colorless pol-ymer which is characterized by high optical properties, environmental (in particular, H2O, O2 and O3) and light resistance. The stability of films of organic-inorganic perovskite without and with a polymer were investigated by XRD, fluorescence spectroscopy and non-contact optical methods. The stability of the films was evaluated by the content of the additional phase of PbI2, which is formed due to the degradation of the organic-inorganic perovskite film CH3NH3PbI3. It was established that the presence of a polymer layer results in improved stability of samples and decrease the rate of surface recombination velocity compared to samples without a polymer layer.
The diffusion length of minority charge carriers of the organic-inorganic perovskite films with the polymeric layer was estimated by the method of spectral dependences of the surface photovoltage. The spectra of surface photovoltage and the diffusion length of minority charge carriers of organic-inorganic perovskites with a polymer layer were compared with the literature data for samples without a polymer layer. This comparison shown that the characteristics of the samples with polymer layer are somewhat worse. It is determined that the organic-inorganic perovskite with the polymer layer is characterized by a smaller diffusion length (by 10%) of the minority charge carriers. The prepared perovskite films CH3NH3PbI3 are promising for the development of effective solar cells.
Correa-Baena J.-P., Abate A., Saliba M., Tress W., Jacobsson T. J., Grätzel M., Hagfeldt A. The rapid evolution of highly efficient perovskite solar cells. Energy Environ. Sci. 2017. 10 (3): 710.
Chen Q., De Marco N., Yang Y. M., Song T.-B., Chen C.-C., Zhao H., Hong Z., Zhou H., Yang Y. Under the spotlight: The organic–inorganic hybrid halide perovskite for optoelectronic applications. Nano Today. 2015. 10 (3): 355.
Zhao W., Yang D., Liu S. F. Organic–inorganic hybrid perovskite with controlled dopant modification and application in photovoltaic device. Small. 2017. 13 (25): 1604153.
Lee M. M., Teuscher J., Miyasaka T., Murakami T. N., Snaith H. J. Efficient hybrid solar cells based on meso-superstructured organometal halide perovskites. Science. 2012. 338 (2): 643.
Cohen B.-E., Gamliel S., Etgar L. Parameters influencing the deposition of methylammonium lead halide iodide in hole conductor free perovskite-based solar cells. APL materials. 2014. 2 (8): 081502.
Im J.-H., Jang I.-H., Pellet N., Grätzel M., Park N.-G. Growth of CH3NH3PbI3 cuboids with controlled size for high-efficiency perovskite solar cells. Nat. Nanotechnol. 2014. 9 (11): 927.
Burschka J., Pellet N., Moon S.-J., Humphry-Baker R., Gao P., Nazeeruddin M. K., Grätzel M. Sequential deposition as a route to high-performance perovskite-sensitized solar cells. Nature. 2013. 499 (7458): 316.
Kim J. H., Williams S. T., Cho N., Chueh C. C., Jen A. K. Y. Enhanced environmental stability of planar heterojunction perovskite solar cells based on blade‐coating. Advanced Energy Materials. 2014. 5 (4): 1401229.
Ahmadian-Yazdi M.-R., Eslamian M. Fabrication of semiconducting methylammonium lead halide perovskite particles by spray technology. Nanoscale research letters. 2018. 13 (1): 6.
Borchert J., Boht H., Fränzel W., Csuk R., Scheer R., Pistor P. Structural investigation of co-evaporated methyl ammonium lead halide perovskite films during growth and thermal decomposition using different PbX2 (X = I, Cl) precursors. Journal of Materials Chemistry A. 2015. 3 (39): 19842.
Domanski K., Alharbi E. A., Hagfeldt A., Grätzel M., Tress W. Systematic investigation of the impact of operation conditions on the degradation behaviour of perovskite solar cells. Nature Energy. 2018. 3 (1): 61.
Giuri A., Masi S., Listorti A., Gigli G., Colella S., Corcione C. E., Rizzo A. Polymeric rheology modifier allows single-step coating of perovskite ink for highly efficient and stable solar cells. Nano Energy. 2018. 54: 400.
Messegee Z., Al Mamun A., Ava T. T., Namkoong G., Abdel-Fattah T. M. Characterization of perovskite (CH3NH3PbI3) degradation with the integration of different polymers for increased stability. Mater. Lett. 2019. 236: 159.
ASTM F391-02, Standard Test Methods for Minority Carrier Diffusion Length in Extrinsic Semiconductors by Measurement of Steady-State Surface Photovoltage. Annual book of ASTM standards 10.05. (West Conshohocken, PA: 2002).
Certificate No. PT-432/14 on the attestation of the Center for testing photocurrent and photovoltaic IFN batteries V.E. Lashkarev National Academy of Sciences of Ukraine. Issued on 08/12/2014 State Enterprise "Ukrmetrteststandard". 2014. The action was prolonged by the decision of the Derzhspozhyvstandart of Ukraine in 2018. [in Ukrainian]
Belous A., Kobylianska S., V’yunov O., Torchyniuk P., Yukhymchuk V., Hreshchuk O. Effect of non-stoichiometry of initial reagents on morphological and structural properties of perovskites CH3NH3PbI3. Nanoscale Res. Lett. 2019. 14 (4): 1.
Kye Y.-H., Yu C.-J., Jong U.-G., Chen Y., Walsh A. Critical role of water in defect aggregation and chemical degradation of perovskite solar cells. J. Phys. Chem. Lett. 2018. 9 (9): 2196.
Vincent B. R., Robertson K. N., Cameron T. S., Knop O. Alkylammonium lead halides. Part 1. Isolated PbI64− ions in (CH3NH3) 4PbI6•2H2O. Can. J. Chem. 1987. 65 (5): 1042.
Rajagopal A., Yao K., Jen A. K. Y. Toward Perovskite Solar Cell Commercialization: A Perspective and Research Roadmap Based on Interfacial Engineering. Adv. Mater. 2018. 30 (32): 1800455.
Chen X., Cao H., Yu H., Zhu H., Zhou H., Yang L., Yin S. Large-area, high-quality organic–inorganic hybrid perovskite thin films via a controlled vapor–solid reaction. Journal of Materials Chemistry A. 2016. 4 (23): 9124.
Roghabadi F. A., Ahmadi V., Aghmiuni K. O. Organic–Inorganic Halide Perovskite Formation: In Situ Dissociation of Cation Halide and Metal Halide Complexes during Crystal Formation. J. Phys. Chem. C. 2017. 121 (25): 13532.
Petrov A. A., Sokolova I. P., Belich N. A., Peters G. S., Dorovatovskii P. V., Zubavichus Y. V., Khrustalev V. N., Petrov A. V., Grätzel M., Goodilin E. A. Crystal structure of DMF-intermediate phases uncovers the link between CH3NH3PbI3 morphology and precursor stoichiometry. J. Phys. Chem. C. 2017. 121 (38): 20739.
Barbieri L., Ferrari A. M., Lancellotti I., Leonelli C., Rincón J. M., Romero M. Crystallization of (Na2O–MgO)–CaO–Al2O3–SiO2 glassy systems formulated from waste products. J. Amer. Ceram. Soc. 2000. 83 (10): 2515.
Saliba M., Correa‐Baena J. P., Grätzel M., Hagfeldt A., Abate A. Perovskite solar cells: from the atomic level to film quality and device performance. Angew. Chem. Int. Ed. 2018. 57 (10): 2554.
Ishchenko A. A. Photonics and molecular design of dye-doped polymers for modern light-sensitive materials. Pure Appl. Chem. 2008. 80 (7): 1525.
Jung E. H., Jeon N. J., Park E. Y., Moon C. S., Shin T. J., Yang T.-Y., Noh J. H., Seo J. Efficient, stable and scalable perovskite solar cells using poly (3-hexylthiophene). Nature. 2019. 567 (7749): 511.
Han T.-H., Lee J.-W., Choi C., Tan S., Lee C., Zhao Y., Dai Z., De Marco N., Lee S.-J., Bae S.-H. Perovskite-polymer composite cross-linker approach for highly-stable and efficient perovskite solar cells. Nature communications. 2019. 10 (1): 520.
Park D. Y., Byun H. R., Kim H., Kim B., Jeong M. S. Enhanced Stability of Perovskite Solar Cells using Organosilane-treated Double Polymer Passivation Layers. J. Korean Phys. Soc. 2018. 73 (11): 1787.
Valero S., Collavini S., Völker S. F., Saliba M., Tress W. R., Zakeeruddin S. M., Grätzel M., Delgado J. L. Dopant-free hole-transporting polymers for efficient and stable perovskite solar cells. Macromolecules. 2019. 52 (6): 2243.
Li W., Mori T., Michinobu T. Perovskite solar cells based on hole-transporting conjugated polymers by direct arylation polycondensation. MRS Communications. 2018. 8 (3): 1244.
Bella F., Griffini G., Correa-Baena J-P. et al. Improving efficiency and stability of perovskite solar cells with photocurable fluoropolymers. Sciences. 2016.354 (6309): 203 – 206.
Hou W., Xiao Y., Han G., Lin J.-Y. The applications of polymers in solar cells: A review. Polymers. 2019. 11 (1): 143.
Kostylyov V. P., Sachenko A. V., Vlasiuk V. M., Sokolovskyi I. O., Kobylianska S. D., Torchyniuk P. V., V'yunov O. I., Belous A. G. Synthesis and investigation of the properties of organic-inorganic perovskite films with non-contact optical methods. arXiv preprint arXiv:1901.07853. 2019.