Laser-Assisted Fabrication of Microphotocapacitors with High Energy Density and Output Voltage

Self-powered devices have great potential in daily applications ranging from portable electronics to wearable body sensors, yet their working lifetime and performance are normally limited by the low energy density of the power unit as well as additional resistive losses induced by connections between electronic and power moieties. Herein, we report an effective programmable laser-assisted fabrication of facilely integrated microphotocapacitors (integrated devices of solar cells and microsupercapacitors, mPCs) exhibiting high output voltage and energy density (32.3 μWh cm^-2). An mPC pack (8 mPCs in series within a size of 3 × 3 cm²) delivers an excellent V_oc of 7.3 V, and an output voltage of 90 V can be obtained with an array of 14 mPC packs when tested outdoors under solar illumination (63 mW cm^-2), setting a new benchmark for integrated self-charging power packs. These devices have also shown good stability (stable operation over 2000 cycles, 2.1 × 10⁴ s) and performance under low- or intermittent-intensity light illuminations, highlighting their abilities to work indoors or under cloudy weather.