▎ 摘　　要

NOVELTY - Method for preparing self-powered flexible droplet sensor based on laser processing technology, involves (i) using pulsed laser based on the photothermal effect to generate porous graphene interdigitated electrodes on the surface of the polyimide film, (ii) stirring polydimethylsiloxane solution, fixing porous graphene finger electrode on the spin coater and fixing the polydimethylsiloxane, pouring the dimethylsiloxane solution on the sample, leaving still, adjusting the rotation speed, moving the sample into the oven and baking for 18-22 minutes, (iii) repeating the step (ii) several times, (iv) baking the sample prepared in the step (iii) in an oven for 1 hour to obtain polydimethylsiloxane, (v) peeling the polydimethylsiloxane film from the polyimide substrate, and transferring the patterned porous graphene to the surface (A) of the polydimethylsiloxane film and (vi) using pulsed laser to cross-scan the sample (B) surface to generate super-hydrophobic structure. USE - The flexible droplet sensor is used for real-time monitoring of clinical intravenous injections or blood transfusions. ADVANTAGE - The flexible droplet sensor has the characteristics of large area rapid preparation, low cost, and easy preparation, and can be conformally attached to the surface of umbrellas and raincoats to collect natural energy. DETAILED DESCRIPTION - Method for preparing self-powered flexible droplet sensor based on laser processing technology, involves (i) using pulsed laser based on the photothermal effect to generate porous graphene interdigitated electrodes on the surface of the polyimide film, (ii) uniformly stirring polydimethylsiloxane solution with a solution mixing ratio of 10:1, removing the bubbles in a vacuum, fixing the porous graphene finger electrode prepared in the step (i) on the spin coater and fixing the polydimethylsiloxane on the spin coater, pouring the dimethylsiloxane solution on the surface of the sample, leaving still for 2 minutes, adjusting the rotation speed of the spin coater to 180-220 rpm for 5-8 seconds, increasing the speed to 90-1100 rpm for 3-8 seconds, moving the sample into the oven and baking for 18-22 minutes, (iii) repeating the step (ii) several times to precisely control the thickness of the spin-coated polydimethylsiloxane to 100-500 microns, (iv) placing the sample prepared in the step (iii) in an oven and baking for 1 hour to fully cure the polydimethylsiloxane, (v) peeling the polydimethylsiloxane film from the polyimide substrate, and transferring the patterned porous graphene to the surface (A) of the polydimethylsiloxane film and (vi) using pulsed laser to cross-scan the sample (B) surface obtained in the step (v) to generate super-hydrophobic structure.