Ballistic-aggregated Carbon Nanofoam in Target-side of Pulsed Laser Deposition for Energy Storage Applications

TL;DR

This study explores using target-side nanofoam from pulsed laser deposition as a binder-free supercapacitor electrode, achieving higher capacitance and cycle stability, thus promoting sustainable nanomaterials utilization.

Contribution

It introduces a novel use of target-side coated materials in pulsed laser deposition as high-performance supercapacitor electrodes, enhancing sustainability and device efficiency.

Findings

Achieved higher volumetric capacitance of 522 mF/cm³ compared to conventional nanofoam.

Demonstrated 104% retention after 10,000 cycles, indicating excellent stability.

Produced ultrafast frequency response with 134 μF/cm² at 120 Hz.

Abstract

In pulsed laser deposition, along the traditionally exploited deposition on the front-side of the plasma-plume, a coating forms on the surface of the target as well. For reproducibility, this residue is usually cleaned and discarded. Here we instead investigate the target-side coated materials and employ them as a binder-free supercapacitor electrode. The ballistic-aggregated, target-side nanofoam is compact and features a larger fraction of sp2-carbon, higher nitrogen content with higher graphitic-N and lower oxygen content with fewer COOH groups than that of diffusive-aggregated conventional nanofoams. They are highly hydrogenated graphite-like amorphous carbon and superhydrophilic. The resulting symmetric micro-supercapacitor delivers higher volumetric capacitance of 522 mF/cm3 at 100 mV/s and 104% retention after 10000 charge-discharge cycles over conventional nanofoam (215 mF/cm3 and 85% retention) with an areal capacitance of 134 {\mu}F/cm2 at 120 Hz and ultrafast frequency response. Utilizing the normally discarded target-side material can therefore enable high performing devices while reducing waste, cost and energy input per usable product. leading towards a greater sustainability on nanomaterials synthesis and deposition techniques.