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La naturaleza de las transiciones radiativas en los nanotubos de nitruro de boro dopados con o
Gaoyang Gou1, Bicai Pan, Lei Shi
1Hefei National Laboratory for Physical Science at Microscale, University of Science and Technology of China, Hefei 230026, PR China.
Journal of the American Chemical Society
|March 13, 2009
Resumen
Las impurezas de oxígeno en los nanotubos de nitruro de boro (BNNT) crean nuevas estructuras que explican las transiciones radiativas observadas. Los cálculos de primer principio revelan cómo estos BNNT dopados con O alteran las propiedades electrónicas y ópticas, lo que confirma los hallazgos experimentales.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Física de la materia condensada Física de la materia condensada
- Nanotecnología La nanotecnología es la nanotecnología.
Sus antecedentes:
- Los espectros experimentales de catodoluminiscencia de los nanotubos de nitruro de boro (BNNT) sugieren que las impurezas de oxígeno inducen transiciones radiativas.
- La configuración estructural precisa y el mecanismo de la influencia del oxígeno en los BNNT siguen sin estar claros.
Objetivo del estudio:
- Para dilucidar el patrón estructural de los BNNTs dopados con oxígeno.
- Para investigar el impacto de las impurezas de sustitución de oxígeno en las propiedades electrónicas y ópticas de BNNTs.
- Proporcionar evidencia teórica para las transiciones radiativas inducidas por oxígeno en BNNTs.
Principales métodos:
- Se utilizaron cálculos basados en el primer principio para predecir configuraciones estables de los BNNT dopados con O.
- La estructura electrónica, las propiedades ópticas y las propiedades vibratorias fueron investigadas computacionalmente.
- Se realizó una comparación con las unidades estructurales de óxido de boro.
Principales resultados:
- Se predijo una configuración de grupo B(3) O(6) novedosa y estable para los BNNT dopados con O, que se asemeja al óxido de boro.
- Los cálculos mostraron que las impurezas sustitutivas de oxígeno introducen estados de brecha similares a los de los donantes.
- Se observaron alteraciones significativas en las propiedades ópticas de los BNNT debido al dopaje de oxígeno.
Conclusiones:
- El estudio aclara el origen de los hallazgos experimentales con respecto a las transiciones radiativas en BNNTs.
- La evidencia teórica apoya la existencia de transiciones radiativas inducidas por impurezas sustitutivas de oxígeno en BNNTs.
- La estructura predicha B(3)O(6) proporciona información sobre el papel del oxígeno en las propiedades de BNNT.
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