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1. Bezerra, Raquel Costabile. Estudo te?rico via DFT da adsor??o de glicerol sobre catalisadores de Pt e Pt-Sn.

Degree: 2015, Universidade Federal do Amazonas

O glicerol ? apontado como um bom canditado para aplica??o em c?culas a combust?vel, contudo, nestes sistemas ? necess?rio um catalisador para oxid?-lo e a intera??o dele com o catalisador n?o ? totalmente compreendida. Assim, neste trabalho, a adsor??o do glicerol sobre as superf?cies de Pt(001) e Pt 3Sn1 (001) foi investigada atrav?s da Teoria do Funcional de Densidade (DFT) fazendo o uso da corre??o de van der Waals para as intera??es de longo alcance. O funcional usado nos c?lculos foi o PBE-GGA. As tr?s estruturas para o glicerol foram constru?das com base em coordenadas reportadas na literatura ou desenhada e otimizadas, sendo tr?s as diferentes estruturas para este ?lcool usadas neste trabalho, as quais foram colocadas nas superf?cies met?licas em diferentes posi??es. As estruturas met?licas foram constru?das como superc?lulas 2x2x1 a partir de suas c?lulas unit?rias. As configura??es do glicerol sobre as superf?cies mostraram que a intera??o de apenas um grupo OH ? mais fraca que a intera??o envolvendo dois ou tr?s grupos OH. Os dados das densidades de estados projetadas sobre as fun??es de ondas (PDOS) indicam que as intera??es do glicerol com as superf?cies ocorrem, principalmente, por meio dos ?tomos de oxig?nio, al?m disso, varia??es nas densidades de cargas ratificam essa coloca??o. Foi verificado ainda que o uso da corre??o de van der Waals favoreceu a configura??o em que o glicerol interage com a as superf?cies atrav?s dos dois ?tomos de oxig?nio dos grupos CH2OH terminais, enquanto que, sem esta corre??o, as configura??es de mais baixa energia continham o ?tomo de oxig?nio do grupo CH2OH central sendo o mais pr?ximo das superf?cies.

Glycerol is considered as a good candidate for fuel cell application, however, in these systems a catalyst is required to oxidize it and its interaction with the catalyst is not fully understood. Thus, in this work, glycerol adsorption on the Pt (001) and Pt3Sn1 (001) surfaces was investigated through the Functional Theory of Density (DFT) using van der Waals correction for long range interactions and using the PBE-GGA functional in our calculations. The three structures for glycerol were constructed based on coordinates reported in the literature or designed and optimized, being the three different structures for this alcohol used in this work, which were placed on the metal surfaces in different positions. The metal structures were constructed as 2x2x1supercells from their unit cells. The glycerol on the surfaces configurations showed that the interaction of only one OH group is weaker than the interaction involving two or three OH groups. The data from projected state densities (PDOS) indicate that glycerol interactions with surfaces occur, mainly, via the oxygen atoms. Also the variations in charge densities confirm this fact. In addition, we verified that the use of van der Waals correction favored the configuration in which glycerol interacts with surfaces through both oxygen atoms of the terminal CH2OH groups, while without this correction the lower energy…

Advisors/Committee Members: Passos, Raimundo Ribeiro, 473576143-87, http://lattes.cnpq.br/2022301821222852, Frota, Hidembergue Ordozgoith da, http://lattes.cnpq.br/5700103079488064, Oliveira, Kelson Mota de, http://lattes.cnpq.br/8167226394049801, [email protected], https://orcid.org/0000-0002-5478-9604.

Subjects/Keywords: C?lulas ? combust?vel; CIENCIAS EXATAS E DA TERRA; DFT; Pt e Pt-Sn; Adsor??o do glicerol

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APA (6th Edition):

Bezerra, R. C. (2015). Estudo te?rico via DFT da adsor??o de glicerol sobre catalisadores de Pt e Pt-Sn. (Masters Thesis). Universidade Federal do Amazonas. Retrieved from https://tede.ufam.edu.br/handle/tede/7436

Chicago Manual of Style (16th Edition):

Bezerra, Raquel Costabile. “Estudo te?rico via DFT da adsor??o de glicerol sobre catalisadores de Pt e Pt-Sn.” 2015. Masters Thesis, Universidade Federal do Amazonas. Accessed December 05, 2020. https://tede.ufam.edu.br/handle/tede/7436.

MLA Handbook (7th Edition):

Bezerra, Raquel Costabile. “Estudo te?rico via DFT da adsor??o de glicerol sobre catalisadores de Pt e Pt-Sn.” 2015. Web. 05 Dec 2020.

Vancouver:

Bezerra RC. Estudo te?rico via DFT da adsor??o de glicerol sobre catalisadores de Pt e Pt-Sn. [Internet] [Masters thesis]. Universidade Federal do Amazonas; 2015. [cited 2020 Dec 05]. Available from: https://tede.ufam.edu.br/handle/tede/7436.

Council of Science Editors:

Bezerra RC. Estudo te?rico via DFT da adsor??o de glicerol sobre catalisadores de Pt e Pt-Sn. [Masters Thesis]. Universidade Federal do Amazonas; 2015. Available from: https://tede.ufam.edu.br/handle/tede/7436

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