title: Synthesis of monoclinic potassium niobate nanowires that are stable at room temperature.
abstract: We report the synthesis of KNbO(3) nanowires (NWs) with a monoclinic phase, a phase not observed in bulk KNbO(3) materials. The monoclinic NWs can be synthesized via a hydrothermal method using metallic Nb as a precursor. The NWs are metastable, and thermal treatment at ∼450 °C changed the monoclinic phase into the orthorhombic phase, which is the most stable phase of KNbO(3) at room temperature. Furthermore, we fabricated energy-harvesting nanogenerators by vertically aligning the NWs on SrTiO(3) substrates. The monoclinic NWs showed significantly better energy conversion characteristics than orthorhombic NWs. Moreover, the frequency-doubling efficiency of the monoclinic NWs was ∼3 times higher than that of orthorhombic NWs. This work may contribute to the synthesis of materials with new crystalline structures and hence improve the properties of the materials for various applications.
authors.affiliation: Department of Nano-Semiconductor Engineering, Korea University, Seoul 136-713, Republic of Korea.
authors.forename: Seungwook
authors.initials: S
authors.lastname: Kim
authors.forename: Ju-Hyuck
authors.initials: JH
authors.lastname: Lee
authors.forename: Jaeyeon
authors.initials: J
authors.lastname: Lee
authors.forename: Sang-Woo
authors.initials: SW
authors.lastname: Kim
authors.forename: Myung Hwa
authors.initials: MH
authors.lastname: Kim
authors.forename: Sungnam
authors.initials: S
authors.lastname: Park
authors.forename: Haegeun
authors.initials: H
authors.lastname: Chung
authors.forename: Yong-Il
authors.initials: YI
authors.lastname: Kim
authors.forename: Woong
authors.initials: W
authors.lastname: Kim
mesh_terms: D053770:Nanowires / Q000737:chemistry*; D009556:Niobium / Q000737:chemistry; D010087:Oxides / Q000138:chemical synthesis* / Q000737:chemistry; D010316:Particle Size; D011188:Potassium / Q000737:chemistry; D013499:Surface Properties; D013696:Temperature
chemical_list: D010087:Oxides; D009556:Niobium; C477466:potassium niobate; D011188:Potassium