You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["Chemical"].

Please return the output as a JSON object of the format: {"Chemical": ["Arsenic", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

Facile solution synthesis of Ag@Pt core-shell nanoparticles with dendritic Pt shells. Ag@Pt nanoparticles with various dendritic Pt shells were successfully synthesized by using nonionic surfactants at room temperature. Our recent study demonstrated that the addition of nonionic surfactant plays an important key role in the synthesis of dendritic Pt nanostructures (J. Am. Chem. Soc., 2010, 132, 13636). Here we extend this synthetic concept to prepare various Ag@Pt nanoarchitectures. The different nanostructured Pt shells on the Ag core were confirmed by ultraviolet-visible absorption spectroscopy and transmission electron microscopy. As a preliminary electrochemical application, the obtained Ag@Pt nanostructures were applied in the methanol oxidation reaction (MOR) in 0.5 M H(2)SO(4) solution containing 0.5 M methanol. The Ag@Pt nanoparticles with thin dendritic Pt shells show superior CO-tolerance performance with a I(f)/I(b) value reaching 3.71. Our Ag@Pt nanostructures with good CO tolerant activity will be prominent catalysts for MOR.
{"Chemical": ["Ag", "methanol", "CO", "H(2)SO(4)", "Pt"]}