Flexible H₂O₂ microfluidic fuel cell using graphene/Prussian blue catalyst for high performance

Microfluidic fuel cells exploit the laminar-flow pattern to eliminate the physical separator in conventional fuel cells, and represent one type of promising devices to power the microelectronics and other niche devices. However, an anolyte-catholyte interface should be strictly guaranteed in previous designs to avoid the unfavourable fuel-oxidant mixing, which increases the system complexity and sacrifices its applicability. In the report, we present a bendable microfluidic fuel cell running on H₂O₂ as sole reactant. Three-dimensional flow-through nickel foam and Prussian blue with reduced graphene oxide serve as the anode and cathode side. We establish the numerical model by COMSOL Multiphysics software to depict the concentration distributions of H₂O₂, O₂ and H⁺ during the normal operation. The microfluidic fuel cell benefits from the efficient mass transportation and reaction kinetics, and achieves a power density of 2.22 W m⁻² with a current density of 7.64 A m⁻². After bending and dropping the device several times, the power-generation property doesn't show any obvious decay, indicating a good stability and consistency. The bendable microfluidic fuel cell using H₂O₂ as sole reactant may enrich our choices of wearable and flexible power sources from super-capacitors, Li-ion batteries, solar cells to fuel cells.