Gwon, Hyo Jin Kang, Na-Ri Lee, Yunju Won, Sung Ok Chang, Hye Jun Choi, Ji-Won Kang, Chong-Yun Kim, Seon Keun Kwon, Beomjin Nahm, Sahn Kim, Ju-Young Kim, Jin-Sang Baek, Seung-Hyub 2024-01-20T03:03:51Z 2024-01-20T03:03:51Z 2021-09-05 2016-10-11 0897-4756 https://pubs.kist.re.kr/handle/201004/123566 Controlling crystalline phases in polymorphic materials is critical not only for the fundamental understanding of the physics of phase formation but also for the technological application of forbidden, but potentially useful physical properties of the nominally unstable phases. Here, using tin oxide (SnO2) as a model system, we demonstrate a new way to enhance the mechanical hardness of an oxide by stabilizing a high-pressure dense phase through nitrogen integration in the oxide. Pristine SnO2 has a tetragonal structure at the ambient pressure, and undergoes phase transitions to orthorhombic and cubic phases with increasing pressure. Leveraging the enhanced reactivity of nitrogen in plasma, we are able to synthesize tin oxynitride (SnON) thin films with a cubic phase same as the high-pressure phase of SnO2. Such nitrogen-stabilized cubic SnON films exhibit a mechanical hardness of similar to 23 +/- 4 GPa, significantly higher than even the nitride counterpart (Sn3N4) as the result of the shortened atomic distance of the denser, high-pressure cubic phase. Moreover, SnON has a heavily doped, n-type semiconducting property with a controllable optical bandgap. Our work will provide new opportunities to search for and to utilize beneficial, but hidden physical properties that exist in a particular phase stable only at extreme conditions. English AMER CHEMICAL SOC VISIBLE-LIGHT IRRADIATION OXYNITRIDE GLASSES ORTHORHOMBIC SNO2 TETRAGONAL PHASE ZIRCONIA STABILIZATION FILMS ELECTRONEGATIVITY TRANSITIONS ELASTICITY Enhancement of Mechanical Hardness in SnOxNy with a Dense High-Pressure Cubic Phase of SnO2 Article 10.1021/acs.chemmater.6b02888 1 CHEMISTRY OF MATERIALS, v.28, no.19, pp.7051 - 7057 CHEMISTRY OF MATERIALS 28 19 7051 7057 scie scopus 000385336500029 2-s2.0-84991369039 Chemistry, Physical Materials Science, Multidisciplinary Chemistry Materials Science Article VISIBLE-LIGHT IRRADIATION OXYNITRIDE GLASSES ORTHORHOMBIC SNO2 TETRAGONAL PHASE ZIRCONIA STABILIZATION FILMS ELECTRONEGATIVITY TRANSITIONS ELASTICITY Polymorphic Phase stabilization Tin oxynitride Aliovalent anion substitution Hardness