Study of the FLG transferring technique on grids and the particle angular scattering characteristics for next-generation space TOF instruments with higher mass resolution

Carbon foils are widely used in time-of-flight (TOF, a measurement method that derives particle velocity from flight time over a defined spatial interval) mass spectrometers, yet their accuracy is constrained by thickness-induced scattering and fragility. Featuring atomic thickness and superior mechanical strength, graphene introduces less angular scattering and delivers improved mass resolution, thereby offering a compelling alternative for space-based TOF systems. Nonetheless, the application of graphene into such systems remains constrained by challenges in transferring it onto mesh grids, which is a key step for its integration in TOF systems. Hence, to achieve an optimal balance among minimal thickness, high graphene coverage, and high grid open fraction, we optimized and adapted a graphene transfer technique suitable for space applications and successfully prepared several few-layer graphene (FLG, graphene with more than 3 atomic layers) samples by this technique. These samples, with 2 nm thickness, a grid open fraction of 40%, and a graphene coverage exceeding 95%, were subsequently irradiated with ion beams to characterize their angular scattering behavior, yielding half-width at half‑maximum (HWHM) values and scattering half‑angles. Computer simulation of the angular scattering experiment was also conducted to validate the experimental measurements. For FLG, scattering half‑angles ranged from 1.33° to 4.76°. Under identical ion species and energy conditions, carbon foils exhibited scattering half‑angles between 1.56° and 11.02°. These results indicate that FLG induces less angular scattering than carbon foils, thereby enhancing measurement accuracy in TOF systems. These findings demonstrate the potential of FLG for next‑generation space plasma instruments and provide a foundation for further investigation. Further development of large-area(>1×1 cm) FLG transfer techniques is still recommended for practical space application.