2D to 3D transition of polymeric carbon nitride nanosheets
Por:
Chamorro-Posada P., Vázquez-Cabo J., Sánchez-Arévalo F.M., Martín-Ramos P., Martín-Gil J., Navas-Gracia L.M., Dante R.C.
Publicada:
1 nov 2014
Resumen:
The transition from a prevalent turbostratic arrangement with low planar interactions (2D) to an array of polymeric carbon nitride nanosheets with stronger interplanar interactions (3D), occurring for samples treated above 650 °C, was detected by terahertz-time domain spectroscopy (THz-TDS). The simulated 3D material made of stacks of shifted quasi planar sheets composed of zigzagged polymer ribbons, delivered a XRD simulated pattern in relatively good agreement with the experimental one. The 2D to 3D transition was also supported by the simulation of THz-TDS spectra obtained from quantum chemistry calculations, in which the same broad bands around 2 THz and 1.5 THz were found for 2D and 3D arrays, respectively. This transition was also in accordance with the tightening of the interplanar distance probably due to an interplanar p bond contribution, as evidenced also by a broad absorption around 2.6 eV in the UV-vis spectrum, which appeared in the sample treated at 650 °C, and increased in the sample treated at 700 °C. The band gap was calculated for 1D and 2D cases. The value of 3.374 eV for the 2D case is, within the model accuracy and precision, in a relative good agreement with the value of 3.055 eV obtained from the experimental results. © 2014 Elsevier Inc.
Filiaciones:
Chamorro-Posada P.:
Dpto. de Teoría de la Señal y Comunicaciones e IT, Universidad de Valladolid, ETSI Telecomunicación, Paseo Belén 15, 47011 Valladolid, Spain
Vázquez-Cabo J.:
Dpto. de Teoría de la Señal y Comunicaciones, Universidad de Vigo, ETSI Telecomunicación, Lagoas Marcosende s/n, Vigo, Spain
Sánchez-Arévalo F.M.:
Univ Nacl Autonoma Mexico, Inst Invest Mat, Mexico City 04510, DF, Mexico
Martín-Ramos P.:
Dpto. de Teoría de la Señal y Comunicaciones e IT, Universidad de Valladolid, ETSI Telecomunicación, Paseo Belén 15, 47011 Valladolid, Spain
Laboratorio de Materiales Avanzados, Advanced Materials Laboratory, Universidad de Valladolid, Avenida de Madrid 44, 34004 Palencia, Spain
Martín-Gil J.:
Laboratorio de Materiales Avanzados, Advanced Materials Laboratory, Universidad de Valladolid, Avenida de Madrid 44, 34004 Palencia, Spain
Navas-Gracia L.M.:
Laboratorio de Materiales Avanzados, Advanced Materials Laboratory, Universidad de Valladolid, Avenida de Madrid 44, 34004 Palencia, Spain
Dante R.C.:
Laboratorio de Materiales Avanzados, Advanced Materials Laboratory, Universidad de Valladolid, Avenida de Madrid 44, 34004 Palencia, Spain
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