NOVELTY - The apparatus (100) has vaporizers (110,120) for vaporizing samples respectively. The heaters (130,140) are used to heat vaporizers respectively. A connector pipe (150) is used to connect vaporizers. The vaporized samples are passed inside reactor (160). A composite structure of powder form is synthesized in the state where adherence surface is electrostatically adhered with composite structure, when samples of gaseous state flow into reactor from pipe and while the samples are instantaneously dispersed by pressure and temperature differences to produce powdery composite structure.    USE - Composite structure synthesizing apparatus for synthesizing metal-metal or metal-carbon hybrid particle used as electrode raw material of metal catalyst for gas phase reactions, fuel cell, and secondary battery. Can also be used in various adsorption agents, absorber, and gas and liquid separation membrane.    ADVANTAGE - Different kinds of composites such as metal-metal or metal-carbon hybrid particle can be synthesized in the state where the adherence surface is adhered with composite structure electrostatically, without the chemical bonding. Mass production of the composite structure is ensured. The synthesized composite structures can be collected easily by simple collection work. The quantity of the synthesized composite particles can be controlled easily by adjusting the diameter of connector pipe in which the precursor of gaseous state is transmitted. The metal-metal or metal-carbon hybrid composite particles can be effectively synthesized by adjusting the reactor temperature. The composite structure property can be controlled effectively. The composite structures of large quantities can be produced even if scale is not changed. The apparatus is effective in the ability to actualize the application object through the change of metal component, or the change of carbon structure.    DETAILED DESCRIPTION - The reactor is provided with a cross section diameter of a relatively large dimension compared with the connector pipe, and is maintained at a temperature lower than pipe temperature. The filter of quartz or a carbon raw material is installed in the lower portion of reactor. The board or metal plate (162) consisting of glass is installed in upper portion of filter. The heating furnace is provided in the circumference of reactor. The inside temperature of reactor is maintained at 60 degrees . The connector pipe is equipped with a heat wire for heating the samples of gaseous state which are transmitted to the reactor via connector pipe. The reaction gas supply device (180) required for reaction of first and second samples is included in the reactor. A recycle device (190) is used for supplying the waste gas which flows out of the reactor to the inside of reactor. The gas supply portion (116) or discharge portion (118) is equipped with a stop cock (SC) for keeping the sample from contacting with air. INDEPENDENT CLAIMS are included for the following:    (1) the reactor for composite structure synthesizing apparatus; and    (2) the composite structure synthesizing method.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the composite structure synthesizing apparatus.    Composite structure synthesizing apparatus (100)    Vaporizers (110,120)    Gas supply portion (116)    Discharge portion (118)    Heaters (130,140)    Connector pipe (150)    Reactor (160)    Metal plate (162)    Reaction gas supply device (180)    Recycle device (190)    Stop cock (SC)