NOVELTY - A graphene material is prepared by plating 500 nm nickel membrane on substrate surface for annealing to serve as catalyst for growing graphene, adjusting optical path and parameter of a laser to enable the facula to be uniformly aligned to the area, introducing the argon gas into the sealed quartz tube for 30 minutes, introducing the hydrogen gas for 5 minutes, opening the laser, introducing methane as a reaction precursor source, and taking hydrogen gas as reducing gas for reaction.    USE - Method for preparation of graphene for preparing electronic device and solar cell (claimed).    ADVANTAGE - The graphene has high electronic transmission feature, good response frequency, and wide optical wave transparency. It can realize high-speed optimization in the preparation of the electronic device and the solar cell conductive thin film material with high optical waveband transmission ratio, thus, the implementation in the qualified graphene material with large area of growth has importance in the development in the electronic technology and the solar cell technology. The method can realize direct heating in the growth area. There is no additional heating area, and the laser can be instantly closed to fast remove the light beam. The method has fast cooling speed and can reduce the growth of the unnecessary multi-layer graphene and realize single-layer growth in the graphene.    DETAILED DESCRIPTION - Preparation of graphene material involves plating 500 nm nickel membrane on substrate surface for annealing to serve as catalyst for growing the graphene. The substrate is put in a quartz tube. A temperature sensor is set for monitoring the temperature of the substrate. A laser is opened. The optical path and parameter of the laser are adjusted to enable the facula to be uniformly aligned to the area selected on the substrate for heating. Argon gas is introduced into the sealed quartz tube. The flow rate is kept to be 200 standard cubic centimeter per minute (sccm) to discharge the air in the quartz tube for 30 minutes. Hydrogen gas is introduced into the sealed quartz tube with the same flow rate for 5 minutes. The laser to be aligned to the substrate area with selective growth is opened for heating. At 900 degrees C, methane is introduced into the sealed quartz tube to serve as the reaction precursor source. Hydrogen gas is taken as the reducing as for reaction at 100 sccm for 3-5 minutes for graphene growth. The laser is closed to remove the light beam. The sample is taken for cooling to obtain the graphene sample with large area of growth.