Abstract: The principle of the direct-current nano-generator driven by ultrasonic waves is studied.It is shown that the nanogenerator is a wonderful disorder-energy harvester,it can convert nanoscale random minor mechanical energy into electrical energy;in other words,it is a wonderful device that can convert mess into order and refine order from disorder.The direct-current value of the nano-generator caused by stochastic vibrations noise is also calculated.Under certain conditions,the direct-current value of the nanogenerator can achieve the level of 240 nA,which can be measured by experiment.

Key words: nano-generator, stochastic vibration, disorder-energy harvester