TY - JOUR

T1 - A Study of Pt/Al2O3 Nanocomposites Obtained by Pulsed Laser Ablation to Be Used as Catalysts of Oxidation Reactions

AU - Fedorova, E. A.

AU - Stadnichenko, A. I.

AU - Slavinskaya, E. M.

AU - Kibis, L. S.

AU - Stonkus, O. A.

AU - Svintsitskiy, D. A.

AU - Lapin, I. N.

AU - Romanenko, A. V.

AU - Svetlichnyi, V. A.

AU - Boronin, A. I.

PY - 2020/2/1

Y1 - 2020/2/1

N2 - Pulsed laser ablation (PLA) in liquids is an effective high-energy method for the synthesis of functional nanomaterials. In the present work, a nanocomposite catalyst Pt/Al2O3(PLA) is prepared by mixing solutions of platinum and aluminium nanodispersions obtained by the PLA method in alcohol and water, respectively. After being dried out, the obtained nanocomposite is thermally treated in air at 400 °C and 550 °C. It is shown by X-ray photoelectron spectroscopy (XPS) and X-ray diffraction that platinum in the composition of the calcined samples stabilizes on the Al2O3 surface in the form of metal nanoparticles. The main crystal structure of η-Al2O3 is determined and impurity phases of Al(OH)3 hydroxide and metallic aluminium are revealed using X-ray powder diffraction (XRPD). The Pt/Al2O3 nanocomposite samples obtained by the PLA method are found to be highly prospective for the use in reactions of catalytic oxidation of CO and NH3. The Pt/Al2O3(PLA) nanocomposites are compared with the Pt/Al2O3 (IMP) catalyst synthesized by the method of solution chemistry. The Pt/Al2O3(IMP) sample containing highly dispersed platinum nanoparticles (1–2 nm) on the γ-Al2O3 surface has a lower T50 value (188 °C) in the reaction of CO oxidation that the PLA catalyst (T50 = 198 °C). At the same time, in the reaction of NH3 oxidation, the PLA catalyst is more active (T50 = 167 °C) than the IMP sample (T50 = 180 °C). The observed regularities are discussed in terms of the dispersion and the oxidation depth of platinum particles in the composition of Pt/Al2O3 catalysts.

AB - Pulsed laser ablation (PLA) in liquids is an effective high-energy method for the synthesis of functional nanomaterials. In the present work, a nanocomposite catalyst Pt/Al2O3(PLA) is prepared by mixing solutions of platinum and aluminium nanodispersions obtained by the PLA method in alcohol and water, respectively. After being dried out, the obtained nanocomposite is thermally treated in air at 400 °C and 550 °C. It is shown by X-ray photoelectron spectroscopy (XPS) and X-ray diffraction that platinum in the composition of the calcined samples stabilizes on the Al2O3 surface in the form of metal nanoparticles. The main crystal structure of η-Al2O3 is determined and impurity phases of Al(OH)3 hydroxide and metallic aluminium are revealed using X-ray powder diffraction (XRPD). The Pt/Al2O3 nanocomposite samples obtained by the PLA method are found to be highly prospective for the use in reactions of catalytic oxidation of CO and NH3. The Pt/Al2O3(PLA) nanocomposites are compared with the Pt/Al2O3 (IMP) catalyst synthesized by the method of solution chemistry. The Pt/Al2O3(IMP) sample containing highly dispersed platinum nanoparticles (1–2 nm) on the γ-Al2O3 surface has a lower T50 value (188 °C) in the reaction of CO oxidation that the PLA catalyst (T50 = 198 °C). At the same time, in the reaction of NH3 oxidation, the PLA catalyst is more active (T50 = 167 °C) than the IMP sample (T50 = 180 °C). The observed regularities are discussed in terms of the dispersion and the oxidation depth of platinum particles in the composition of Pt/Al2O3 catalysts.

KW - aluminium oxide

KW - platinum

KW - powder XRD

KW - pulsed laser ablation

KW - XPS

KW - THERMAL-STABILITY

KW - TEMPERATURE AMMONIA OXIDATION

KW - OXIDIZED PLATINUM

KW - PT/CEO2 CATALYSTS

KW - CO OXIDATION

KW - PT/AL2O3 CATALYSTS

KW - CARBON-MONOXIDE

KW - PD/AL2O3 CATALYSTS

KW - PROGRESSIVE OXIDATION

KW - MOLECULAR-OXYGEN

UR - http://www.scopus.com/inward/record.url?scp=85087957353&partnerID=8YFLogxK

U2 - 10.1134/S0022476620020171

DO - 10.1134/S0022476620020171

M3 - Article

AN - SCOPUS:85087957353

VL - 61

SP - 316

EP - 329

JO - Journal of Structural Chemistry

JF - Journal of Structural Chemistry

SN - 0022-4766

IS - 2

ER -