## 1 Introduction  
Platinum is one of the most widely used active components of catalysts for a wide range of oxidative reactions. Platinum catalysts are used for complete oxidation of CO, soot and hydrocarbons [1; 2], epoxidation [3], in fuel cells [4] and selective oxidation [5; 6]. Most commonly, platinum is used in supported form. Depending on the type of the catalytic process, different supports are chosen: carbon materials [7], inert oxides such as SiO\({}_{2}\)[8] or Al\({}_{2}\)O\({}_{3}\)[9], reducible oxides, e.g., CeO\({}_{2}\)[10], Fe\({}_{2}\)O\({}_{3}\)[11], TiO\({}_{2}\)[12]. When using reducible oxide supports a high degree of the platinum interaction with the support (strong metal-support interaction, SMSI) can be achieved. This may result in formation of Pt particles of specific morphology, clusters, ionic Pt forms stabilized in the support oxide lattice [13], or isolated platinum sites on the surface [14].  
For many reactions an increased dispersion of the active component helps improving activity of the catalysts [15]. However, in some cases, high dispersion of the active component is not beneficial [16]. For instance, selective oxidation of ammonia to N\({}_{2}\) (ammonia slip removal) proceeds most efficiently on platinum nanoparticles with sizes of at least 2 and up to 10 nm [9; 17] supported on aluminum, niobium, silicon or titanium oxides. The latter is known for its strong interaction with platinum when heated in reducing atmosphere. The Pt/TiO\({}_{2}\) interaction, on the one hand, can stabilize Pt particles on the surface. On the other hand, it might result in Pt encapsulation by the support, preventing adsorption of reagents [18; 19]. It is also known that at high temperatures a phase transformation of TiO\({}_{2}\) from anatase to rutile can occur leading to a loss of the catalyst activity [20].  
For industrial applications, catalyst stability is required, so thermal stability of the active component is of high importance. Using TiO\({}_{2}\) as a support might help to stabilize platinum particles of required sizes and oxidation states on the surface due to the SMSI. The metal-support interaction is ensured by defects of the support surface. Therefore, the most suitable synthesis methods are those which use nonequilibrium processes to produce structures with high density of defects: burning a precursor solution (solution-combustion) [21; 22], spraying in a flame (spray pyrolysis) [23; 24], atomization in electric discharge [25; 26] or laser evaporation [27; 28; 29]. Pulsed laser ablation (PLA) in liquid phase is a simple and environmentally friendly method for obtaining dispersions of particles with a high density of defects. The pulsed laser ablation (PLA)-prepared dispersions of nanoparticles can be further used for the synthesis of powder catalysts. The efficiency of the PLA technique for preparation of powder catalysts was previously shown for a number of catalytic systems based on ceria, alumina, and iron oxides in which either the support nanoparticles (NPs) or Pt NPs were prepared by the PLA [30; 31; 32].  
The aim of this work was to study the influence of the TiO\({}_{2}\) support synthesized by the PLA technique on the catalytic performance of Pt/TiO\({}_{2}\) catalysts during selective oxidation of ammonia to N\({}_{2}\) (ammonia slip catalysts, ASCs).