Noninvasive imaging of the atomic arrangement in two-dimensional (2D) Ruddlesden-Popper hybrid perovskites (RPPs) is challenging because of the insulating nature and softness of the organic layers. Here, we demonstrate a sub-angstrom resolution imaging of both soft organic layers and inorganic framework in a prototypical 2D lead-halide RPP crystal via combined tip-functionalized scanning tunneling microscopy (STM) and noncontact atomic force microscopy (ncAFM) corroborated by theoretical simulations. STM measurements unveil the atomic reconstruction of the inorganic lead-halide lattice and overall twin-domain composition of the RPP crystal, while ncAFM measurements with a CO-tip enable nonperturbative visualization of the cooperative reordering of surface organic cations driven by their hydrogen bonding interactions with the inorganic lattice. Moreover, such a joint technique also allows for the atomic-scale imaging of the electrostatic potential variation across the twin-domain walls, revealing alternating quasi-1D electron and hole channels at neighboring twin boundaries, which may influence in-plane exciton transport and dissociation.

Centre for Advanced 2D Materials National University of Singapore 6 Science Drive 2 Singapore 117546 Singapore

Department of Applied Physics The Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong China

Department of Chemistry National University of Singapore 3 Science Drive 3 Singapore 117543 Singapore

Department of Physics National University of Singapore Blk S12 Science Drive 3 Singapore 117551 Singapore

Institute of Physics The Czech Academy of Sciences 162 00 Prague Czech Republic

Regional Centre of Advanced Technologies and Materials Palacký University 78371 Olomouc Czech Republic

Zobrazit více v PubMed

Grancini G., Nazeeruddin M. K., Dimensional tailoring of hybrid perovskites for photovoltaics. Nat. Rev. Mater. 4, 4–22 (2019).

Leng K., Fu W., Liu Y., Chhowalla M., Loh K. P., From bulk to molecularly thin hybrid perovskites. Nat. Rev. Mater. 5, 482–500 (2020).

Dou L., Wong A. B., Yu Y., Lai M., Kornienko N., Eaton S. W., Fu A., Bischak C. G., Ma J., Ding T., Ginsberg N. S., Wang L. W., Alivisatos A. P., Yang P., Atomically thin two-dimensional organic-inorganic hybrid perovskites. Science 349, 1518–1521 (2015). PubMed

Smith M. D., Crace E. J., Jaffe A., Karunadasa H. I., The diversity of layered halide perovskites. Annu. Rev. Mat. Res. 48, 111–136 (2018).

Smith I. C., Hoke E. T., Solis-Ibarra D., McGehee M. D., Karunadasa H. I., A layered hybrid perovskite solar-cell absorber with enhanced moisture stability. Angew. Chem. Int. Ed. 126, 11414–11417 (2014). PubMed

Katan C., Mercier N., Even J., Quantum and dielectric confinement effects in lower-dimensional hybrid perovskite semiconductors. Chem. Rev. 119, 3140–3192 (2019). PubMed

Milot R. L., Sutton R. J., Eperon G. E., Haghighirad A. A., Martinez Hardigree J., Miranda L., Snaith H. J., Johnston M. B., Herz L. M., Charge-carrier dynamics in 2D hybrid metal–halide perovskites. Nano Lett. 16, 7001–7007 (2016). PubMed

Blancon J.-C., Stier A. V., Tsai H., Nie W., Stoumpos C. C., Traoré B., Pedesseau L., Kepenekian M., Katsutani F., Noe G. T., Kono J., Tretiak S., Crooker S. A., Katan C., Kanatzidis M. G., Crochet J. J., Even J., Mohite A. D., Scaling law for excitons in 2D perovskite quantum wells. Nat. Commun. 9, 2254 (2018). PubMed PMC

Gao P., Yusoff A. R. B. M., Nazeeruddin M. K., Dimensionality engineering of hybrid halide perovskite light absorbers. Nat. Commun. 9, 5028 (2018). PubMed PMC

Abdelwahab I., Dichtl P., Grinblat G., Leng K., Chi X., Park I.-H., Nielsen M. P., Oulton R. F., Loh K. P., Maier S. A., Giant and tunable optical nonlinearity in single-crystalline 2D perovskites due to excitonic and plasma effects. Adv. Mater. 31, 1902685 (2019). PubMed

Chen Y., Sun Y., Peng J., Tang J., Zheng K., Liang Z., 2D Ruddlesden-Popper perovskites for optoelectronics. Adv. Mater. 30, 1703487 (2018). PubMed

Cao D. H., Stoumpos C. C., Farha O. K., Hupp J. T., Kanatzidis M. G., 2D Homologous perovskites as light-absorbing materials for solar cell applications. J. Am. Chem. Soc. 137, 7843–7850 (2015). PubMed

Cui P., Wei D., Ji J., Huang H., Jia E., Dou S., Wang T., Wang W., Li M., Planar p–n homojunction perovskite solar cells with efficiency exceeding 21.3%. Nature Energy 4, 150–159 (2019).

Tsai H., Nie W., Blancon J. C., Stoumpos C. C., Asadpour R., Harutyunyan B., Neukirch A. J., Verduzco R., Crochet J. J., Tretiak S., Pedesseau L., Even J., Alam M. A., Gupta G., Lou J., Ajayan P. M., Bedzyk M. J., Kanatzidis M. G., Mohite A. D., High-efficiency two-dimensional Ruddlesden-Popper perovskite solar cells. Nature 536, 312–316 (2016). PubMed

Shi E., Yuan B., Shiring S. B., Gao Y., Akriti, Guo Y., Su C., Lai M., Yang P., Kong J., Savoie B. M., Yu Y., Dou L., Two-dimensional halide perovskite lateral epitaxial heterostructures. Nature 580, 614–620 (2020). PubMed

Pan D., Fu Y., Spitha N., Zhao Y., Roy C. R., Morrow D. J., Kohler D. D., Wright J. C., Jin S., Deterministic fabrication of arbitrary vertical heterostructures of two-dimensional Ruddlesden-Popper halide perovskites. Nat. Nanotechnol. 16, 159–165 (2021). PubMed

Leng K., Abdelwahab I., Verzhbitskiy I., Telychko M., Chu L., Fu W., Chi X., Guo N., Chen Z., Chen Z., Zhang C., Xu Q.-H., Lu J., Chhowalla M., Eda G., Loh K. P., Molecularly thin two-dimensional hybrid perovskites with tunable optoelectronic properties due to reversible surface relaxation. Nat. Mater. 17, 908–914 (2018). PubMed

Deng S., Shi E., Yuan L., Jin L., Dou L., Huang L., Long-range exciton transport and slow annihilation in two-dimensional hybrid perovskites. Nat. Commun. 11, 664 (2020). PubMed PMC

Seitz M., Magdaleno A. J., Alcázar-Cano N., Meléndez M., Lubbers T. J., Walraven S. W., Pakdel S., Prada E., Delgado-Buscalioni R., Prins F., Exciton diffusion in two-dimensional metal-halide perovskites. Nat. Commun. 11, 2035 (2020). PubMed PMC

Straus D. B., Kagan C. R., Electrons, excitons, and phonons in two-dimensional hybrid perovskites: Connecting structural, optical, and electronic properties. J. Phys. Chem. Lett. 9, 1434–1447 (2018). PubMed

Mauck C. M., Tisdale W. A., Excitons in 2D organic–inorganic halide perovskites. Trends Chem. 1, 380–393 (2019).

Baldwin A., Delport G., Leng K., Chahbazian R., Galkowski K., Loh K. P., Stranks S. D., Local energy landscape drives long-range exciton diffusion in two-dimensional halide perovskite semiconductors. J. Phys. Chem. Lett. 12, 4003–4011 (2021). PubMed PMC

Rothmann M. U., Kim J. S., Borchert J., Lohmann K. B., O’Leary C. M., Sheader A. A., Clark L., Snaith H. J., Johnston M. B., Nellist P. D., Herz L. M., Atomic-scale microstructure of metal halide perovskite. Science 370, eabb5940 (2020). PubMed

Zhang D., Zhu Y., Liu L., Ying X., Hsiung C.-E., Sougrat R., Li K., Han Y., Atomic-resolution transmission electron microscopy of electron beam-sensitive crystalline materials. Science 359, 675–679 (2018). PubMed

Yuanyuan Z., Sternlicht H., Padture N. P., Transmission electron microscopy of halide perovskite materials and devices. Joule 3, 641–661 (2019).

Chen S., Gao P., Challenges, myths, and opportunities of electron microscopy on halide perovskites. J. App. Phys. 128, 010901 (2020).

Giessibl F. J., The Qplus sensor, a powerful core for the atomic force microscope. Rev. Sci. Instrum. 90, 011101 (2019). PubMed

Labidi H., Koleini M., Huff T., Salomons M., Cloutier M., Pitters J., Wolkow R. A., Indications of chemical bond contrast in AFM images of a hydrogen-terminated silicon surface. Nat. Commun. 8, 14222 (2017). PubMed PMC

Gross L., Mohn F., Moll N., Liljeroth P., Meyer G., The chemical structure of a molecule resolved by atomic force microscopy. Science 325, 1110–1114 (2009). PubMed

de Oteyza D. G., Gorman P., Chen Y.-C., Wickenburg S., Riss A., Mowbray D. J., Etkin G., Pedramrazi Z., Tsai H.-Z., Rubio A., Crommie M. F., Fischer F. R., Direct imaging of covalent bond structure in single-molecule chemical reactions. Science 340, 1434–1437 (2013). PubMed

Jelínek P., High resolution SPM imaging of organic molecules with functionalized tips. J. Phys.-Condens. Mat. 29, 343002 (2017). PubMed

Peng J., Guo J., Hapala P., Cao D., Ma R., Cheng B., Xu L., Ondráček M., Jelínek P., Wang E., Jiang Y., Weakly perturbative imaging of interfacial water with submolecular resolution by atomic force microscopy. Nat. Commun. 9, 122 (2018). PubMed PMC

Shiotari A., Sugimoto Y., Ultrahigh-resolution imaging of water networks by atomic force microscopy. Nat. Commun. 8, 14313 (2017). PubMed PMC

Hsu H.-C., Huang B.-C., Chin S.-C., Hsing C.-R., Nguyen D.-L., Schnedler M., Sankar R., Dunin-Borkowski R. E., Wei C.-M., Chen C.-W., Ebert P., Chiu Y.-P., Photodriven dipole reordering: Key to carrier separation in metalorganic halide perovskites. ACS Nano 13, 4402–4409 (2019). PubMed

Hieulle J., Wang X., Stecker C., Son D.-Y., Qiu L., Ohmann L. R., Ono L. K., Mugarza A., Yan Y., Qi Y., Unraveling the impact of halide mixing on perovskite stability. J. Am. Chem. Soc. 141, 3515–3523 (2019). PubMed PMC

Stecker C., Liu K., Hieulle J., Ohmann R., Liu Z., Ono L. K., Wang G., Qi Y., Surface defect dynamics in organic−inorganic hybrid perovskites: From mechanism to interfacial properties. ACS Nano 13, 12127–12136 (2019). PubMed

She L., Liu M., Li X., Cai Z., Zhong D., Growth and interfacial structure of methylammonium lead iodide thin films on Au(111). Surf. Sci. 656, 17–23 (2017).

She L., Liu M., Zhong D., Atomic structures of CH3NH3PbI3 (001) surfaces. ACS Nano 10, 1126–1131 (2016). PubMed

Ohmann R., Ono L. K., Kim H.-S., Lin H., Lee M. V., Li Y., Park N.-G., Qi Y., Real-space imaging of the atomic structure of organic–inorganic perovskite. J. Am. Chem. Soc. 137, 16049–16054 (2015). PubMed

Hieulle J., Luo S., Son D. Y., Jamshaid A., Stecker C., Liu Z., Na G., Yang D., Ohmann R., Ono L. K., Zhang L., Qi Y., Imaging of the atomic structure of all-inorganic halide perovskites. J. Phys. Chem. Lett. 11, 818–823 (2020). PubMed

Heijden N. J., Hapala P., Rombouts J. A., Lit J., Smith D., Mutombo P., Švec M., Jelínek P., Swart I., Characteristic contrast in Δfmin maps of organic molecules using atomic force microscopy. ACS Nano 10, 8517–8525 (2016). PubMed

Stoumpos C. C., Cao D. H., Clark D. J., Young J., Rondinelli J. M., Jang J. I., Hupp J. T., Kanatzidis M. G., Ruddlesden-Popper hybrid lead iodide perovskite 2D homologous semiconductors. Chem. Mater. 28, 2852–2867 (2016).

Billing D. G., Lemmerer A., Synthesis, characterization and phase transitions in the inorganic–organic layered perovskite-type hybrids [(CnH2n + 1NH3)2PbI4], n = 4, 5 and 6. Acta Crystallogr. 63, 735–747 (2007). PubMed

Leguy A. M. A., Frost J. M., McMahon A. P., Sakai V. G., Kockelmann W., Law C. H., Li X., Foglia F., Walsh A., O’Regan B. C., Nelson J., Cabral J. T., Barnes P. R. F., The dynamics of methylammonium ions in hybrid organic–inorganic perovskite solar cells. Nat. Commun. 6, 7124 (2015). PubMed PMC

Motta C., El-Mellouhi F., Kais S., Tabet N., Alharbi F., Sanvito S., Revealing the role of organic cations in hybrid halide perovskite CH3NH3PbI3. Nat. Commun. 6, 7026 (2014). PubMed PMC

Hapala P., Kichin G., Wagner C., Stefan Tautz F., Temirov R., Jelínek P., Mechanism of high-resolution STM/AFM imaging with functionalized tips. Phys. Rev. B 90, 085421 (2014). PubMed

Krejčí O., Hapala P., Ondráček M., Jelínek P., Principles and simulations of high-resolution STM imaging with a flexible tip apex. Phys. Rev. B 95, 045407 (2017).

Hapala P., Temirov R., Tautz F. S., Jelínek P., Origin of high-resolution IETS-STM images of organic molecules with functionalized tips. Phys. Rev. Lett. 113, 226101 (2014). PubMed

Liu Y., Collins L., Proksch R., Kim S., Watson B. R., Doughty B., Calhoun T. R., Ahmadi M., Ievlev A. V., Jesse S., Retterer S. T., Belianinov A., Xiao K., Huang J., Sumpter B. G., Kalinin S. V., Hu B., Ovchinnikova O. S., Chemical nature of ferroelastic twin domains in CH3NH3PbI3 perovskite. Nat. Mater. 17, 1013–1019 (2018). PubMed

Bertolotti F., Protesescu L., Kovalenko M. V., Yakunin S., Cervellino A., Billinge S. J. L., Terban M. W., Pedersen J. S., Masciocchi N., Guagliardi A., Coherent nanotwins and dynamic disorder in cesium lead halide perovskite nanocrystals. ACS Nano 11, 3819–3831 (2017). PubMed PMC

Hermes I. M., Bretschneider S. A., Bergmann V. W., Li D., Klasen A., Mars J., Tremel W., Laquai F., Butt H. J., Mezger M., Berger R., Rodriguez B. J., Weber S. A. L., Ferroelastic fingerprints in methylammonium lead iodide perovskite. J. Phys. Chem. C 120, 5724–5731 (2016).

Kutes Y., Ye Y. L., Zhou Y., Pang S., Huey B. D., Padture N. P., Direct observation of ferroelectric domains in solution-processed CH3NH3PbI3 perovskite thin films. J. Phys. Chem. Lett. 5, 3335–3339 (2014). PubMed

Rothmann M. U., Li W., Zhu Y., Bach Y., Spiccia L., Etheridge J., Cheng Y.-B., Direct observation of intrinsic twin domains in tetragonal CH3NH3PbI3. Nat. Commun. 8, 14547 (2017). PubMed PMC

Warwick A. R., Íñiguez J., Haynes P. D., Bristowe N. C., First-principles study of ferroelastic twins in halide perovskites. J. Phys. Chem. Lett. 10, 1416–1421 (2019). PubMed

Liu S., Zheng F., Koocher N. Z., Takenaka H., Wang F., Rappe A. M., Ferroelectric domain wall induced band gap reduction and charge separation in organometal halide perovskites. J. Phys. Chem. Lett. 6, 693–699 (2015). PubMed

Melitz W., Shen J., Kummel A. C., Lee S., Kelvin probe force microscopy and its application. Surf. Sci. Rep. 66, 1–27 (2011).

Sherkar T. S., Jan Anton Koster L., Can ferroelectric polarization explain the high performance of hybrid halide perovskite solar cells? Phys. Chem. Chem. Phys. 18, 331–338 (2015). PubMed

Bi F., Markov S., Wang R., Kwok Y. H., Zhou W., Liu L., Zheng X., Chen G. H., Yam C. Y., Enhanced photovoltaic properties induced by ferroelectric domain structures in organometallic halide perovskites. J. Phys. Chem. C 121, 11151–11158 (2017).

Frost J. M., Butler K. T., Brivio F., Hendon C. H., Schilfgaarde M., Walsh A., Atomistic origins of high-performance in hybrid halide perovskite solar cells. Nano Lett. 14, 2584–2590 (2014). PubMed PMC

Li Y., Behtash M., Wong J., Yang K., Enhancing ferroelectric dipole ordering in organic–inorganic hybrid perovskite CH3NH3PbI3: Strain and doping engineering. J. Phys. Chem. C 122, 177–184 (2018).

Jones T. W., Osherov A., Alsari M., Sponseller M., Duck B. C., Jung Y. K., Settens C., Niroui F., Brenes R., Stan C. V., Li Y., Abdi-Jalebi M., Tamura N., Macdonald J. E., Burghammer M., Friend R. H., Bulović V., Walsh A., Wilson G. J., Lilliu S., Stranks S. D., Lattice strain causes non-radiative losses in halide perovskites. Energy Environ. Sci. 12, 596–606 (2019).

Xiao X., Zhou J., Song K., Zhao J., Zhou Y., Rudd P. N., Han Y., Li J., Huang J., Layer number dependent ferroelasticity in 2D Ruddlesden–Popper organic-inorganic hybrid perovskites. Nat Commun. 12, 1332 (2021). PubMed PMC

Schuler B., Qiu D. Y., Refaely-Abramson S., Kastl C., Chen C. T., Barja S., Koch R. J., Ogletree D. F., Aloni S., Schwartzberg A. M., Neaton J. B., Louie S. G., Weber-Bargioni A., Large spin-orbit splitting of deep in-gap defect states of engineered sulfur vacancies in monolayer WS2. Phys. Rev. Lett. 123, 076801 (2019). PubMed

Schulz F., Ritala J., Krejčí O., Seitsonen A. P., Foster A. S., Liljeroth P., Elemental identification by combining atomic force microscopy and Kelvin probe force microscopy. ACS Nano 12, 5274–5283 (2018). PubMed PMC

Lewis J. P., Jelínek P., Ortega J., Demkov A. A., Trabada D. G., Haycock B., Wang H., Adams G., Tomfohr J. K., Abad E., Wang H., Drabold D. A., Advances and applications in the FIREBALL ab initio tight-binding molecular-dynamics formalism. Phys. Status Solidi B. 248, 1989–2007 (2011).

Becke A. D., Density-functional exchange-energy approximation with correct asymptotic behavior. Phys. Rev. A 38, 3098–3100 (1988). PubMed

Lee C., Yang W., Parr R. G., Development of the Colle-Salvetti correlation-energy formula into a functional of the electron density. Phys. Rev. B 37, 785–789 (1988). PubMed

Grimme S., Ehrlich S., Goerigk L., Effect of the damping function in dispersion corrected density functional theory. J. Comput. Chem. 32, 1456–1465 (2011). PubMed

Basanta M. A., Dappe Y. J., Jelínek P., Ortega J., Optimized atomic-like orbitals for first-principles tight-binding molecular dynamics. J. Comput. Mater. Sci. 39, 759–766 (2007).

Leng K., Wang L., Shao Y., Abdelwahab I., Grinblat G., Verzhbitskiy I., Li R., Cai Y., Chi X., Fu W., Song P., Rusydi A., Eda G., Maier S. A., Loh K. P., Electron tunneling at the molecularly thin 2D perovskite and graphene van der Waals interface. Nat. Commun. 11, 5483 (2020). PubMed PMC

Gross L., Mohn F., Liljeroth P., Repp J., Giessibl F., Meyer G., Measuring the charge state of an adatom with noncontact atomic force microscopy. Science 324, 1428–1431 (2009). PubMed