Fig. 5E Tunneling Electron Microscope (TEM) image of nanometer spherical silica-coat Pt--Ni particles (NP-4) for use as Nissan fuel cell catalyst after being fired in the air atmosphere
In U.S. Patent Application 20090291352, Nissan and Kyushu University, National University Corporation researchers reveal a superior electrode materials for proton exchange membrane fuel cells using platinum and nickel catalyst supported on carbon nanotubes.
According to inventors Kenzo Oshihara, Katsuo Suga, Masahiro Kishida and Sakae Takenaka the electrode material is characterized by including: catalyst particles formed by performing inclusion, by a porous inorganic material, for conductive supports and metal (noble metal) particles arranged on the conductive supports. This is because it becomes difficult to ensure electron conductivity when the inclusion of the metal particles (Pt particles and the like) is performed simply by the porous inorganic material (SiO2 and the like) in the case of performing the inclusion by the porous inorganic material in order to prevent elution of the metal (noble metal) particles. The metal particles (Pt particles and Ni) are supported (arranged) on the conductive supports, and the inclusion is performed while putting the metal particles (Pt particles and the like) into centers of the conductive supports, thus making it possible to ensure such electron conduction while suppressing movement of such metal (Pt and Ni)
FIG. 3A shows a TEM image of a CNT of a columnar and/or tubular conductive support for nanocatalyst particles of platinum and nickel.
FIG. 5A is a process schematic view specifically showing a preparation method of the production method of the catalyst particles of the electrode material for the fuel cell. The nanoparticles are added to the TEOS as the precursor of the porous inorganic material; and the ( NP-1,3,4) ammonia and the (NP-2, 5) trithylamine, which are the basic catalysts for the hydrolysis of the TEOS, and the hydrolysis/condensation reaction is performed for an obtained mixture, whereby spherical silica-coat Pt--Ni particles are synthesized