Eye-wearable Ti₃C₂T_x MXene-based micro-supercapacitor as a power unit for intraocular pressure applications

Ocular devices worn on human eyeballs with hemispherical appearance and intelligent functions are expected to perform continuous and nondestructive oculopathy disease management because human eyes contain abundant physiological and biochemical information. However, fabricating and integrating different devices on the hemispherical surface with varying curvature remains a challenge. Herein, we report a Ti₃C₂T_x MXene-based hemispherical integrated system that connects a micro-supercapacitor (MSC) and strain sensors to form self-powered devices for intraocular pressure monitoring. The use of the same Ti₃C₂T_x MXene material as the electrode material of MSC and piezoresistive films of the strain sensors greatly reduces the complexity of the manufacturing process. The high specific capacitance (32 mF cm⁻²) at a scan rate of 5 mV s⁻¹ and energy density (10 mW h cm⁻²) of the Ti₃C₂T_x MXene-based MSC enable stable output voltage to drive the strain sensor. Meanwhile, the Ti₃C₂T_x strain sensor provides a superior sensitivity of 0.014 mmHg⁻¹ and a wide sensing range varying from 0 to 50 mmHg, which can realize continuous IOP monitoring. Furthermore, the self-powered hemispherical integrated device provides rapid and stable response to different IOP, holding great promise for oculopathy diagnosis and treatment.