Water adsorption induced in-plane domain switching on BaTiO3 surface

Abstract

In this study, the influences of the adsorption of water molecules on the changes in the atomic and electric structures of BaTiO3 surface were investigated using ab initio calculation. Water molecules are molecularly and dissociatively adsorbed on the BaTiO3 surface, which makes electrons transfer from water molecules to the BaTiO3 surface. The redistribution of electrons in the BaTiO3 surface layers weakens the Ba-O interactions and strengthens the Ti-O interactions, so that the Ti atom shifts in TiO2 plane, i.e., an in-plane domain switching. The adsorption of water molecules on BaTiO3 surfaces also results in a reduction in the surface rumpling.

Freestanding Perovskite Oxide Films: Synthesis, Challenges, and Properties

“…[57,56] For example, Ca 2 SrAl 2 O 6 was used as a seed sacrificial layer for La 0.7 Ca 0.3 MnO 3 growth due to the nearly perfect lattice match (<0.1%). [55] The minimization lattice mismatches SrTiO 3 [12,[19][20][21][22][23] La x Sr 1−x MnO 3 [19,28,58] BaTiO 3 [59][60][61][62][63] BiFeO 3 [64,65] SrRuO 3 [27,60] LaNiO 3 [66] BiMnO 3 [67] Sr 2 IrO 4 [68] Fe 3 O 4 [69,70] CeO 2 [71] La 0.7 Ca 0.3 MnO 3 [72] [(La 0.7 Sr 0.3 MnO 3 ) 5 /(SrTiO SrTiO 3 [32] n-SrTiO 3 /n-PbTiO 3 /n-SrTiO 3 [33] [(PbTiO 3 ) 16 /(SrTiO 3 ) 16 ] 8 [33] PPC PMMA Water RT -Sr The synthesis method of each sacrificial thin film is shown along with synthesis conditions, substrates, and etching conditions; In the table, T, P O 2 , P Ar , and E indicate the synthesis temperature, pressure of oxygen gas, pressure of argon gas, and laser energy density, respectively; The list of perovskite oxide membranes obtained, the substrate, and the transfer method are also shown; In the column of etching condition, water and RT represent deionized water and room temperature; d, h, and m denote days, hours, and minutes, respectively. can largely improve the quality of the released membranes by hindering the formation of cracks, [55] which has motivated the exploration of sacrificial layers such as Ca 2 SrAl 2 O 6 ( [56,55,[52][53][54] However, small Ca ions can make more distorted geometri...…”

“…[12] Last, it is worthwhile to mention that target materials might also react with water, for example, BaTiO 3 (BTO), which could lead to Ti ion displacements in the TiO 2 plane and surface oxygen vacancies due to the hydroxylation of the first BaO layer. [60,61] Therefore, care should be taken when choosing the sacrificial layers and the target material.…”

Ferroelectric polarization switching induced from water adsorption in BaTiO3 ultrathin films

“…Despite the great importance of this phenomenon and potential applications, up to now there is no study describing the interaction of water with one of the most important ferroelectric materials, BaTiO 3 (BTO) presenting an out-of-plane polarization. Theoretically, only studies [20][21][22] describing water adsorption on in-plane polarized BaTiO 3 have been conducted.…”

Water printing of ferroelectric polarization

“…Although it has been recognized that the polarization of ferroelectrics may potentially determine their surface chemistry over 60 years ago 22 , the converse effect remains a mystery. Multiple physical and chemical processes, e.g., molecular adsorption 23 – 25 , the concomitant electron transfer 26 , were proposed to occur at the surface of ferroelectrics when it was exposed to liquids, which may change the surface polarity (e.g., LiNbO 3 , BaTiO 3 ) 23 , 27 . However, the charge transfer process becomes very complicated because both molecular/ion adsorption and dissociative adsorption coexist on these polar surfaces 23 .…”