Improvement of photoemission performance of graphene/metal van der Waals heterojunction photocathode

Yijun Zhang; Song Tang; Yu Jiang; Zehao Tong; Shiman Li; Yunsheng Qian; Rongguo Fu; Feng Shi; Gangcheng Jiao

doi:10.1117/12.3014504

18 June 2024 Improvement of photoemission performance of graphene/metal van der Waals heterojunction photocathode

Yijun Zhang, Song Tang, Yu Jiang, Zehao Tong, Shiman Li, Yunsheng Qian, Rongguo Fu, Feng Shi, Gangcheng Jiao

Proceedings Volume 13015, Photosensitive Materials and their Applications III; 1301514 (2024) https://doi.org/10.1117/12.3014504
Event: SPIE Photonics Europe, 2024, Strasbourg, France

Abstract

Photocathodes as photoelectric conversion materials play a key role in vacuum photodetectors, accelerator-based light sources, and ultrafast electron microscopy. Since graphene has unique properties such as gas impermeability, electron transparency, a large specific surface area, and atomic thinness, the graphene/metal van der Waals heterojunction material may provide the possibility to improve the photoemission performance of metal photocathodes through surface modification. The specific Cs/O activation process was performed on the surface of graphene/copper heterojunction material. Its photoemission behaviors, including light-excited current, spectral response, and degradation characteristic, were investigated to verify the effect of surface modification on the improvement of photoemission performance. The experimental results show that, by preliminary Cs/O activation, the graphene/Cu photocathode can extend the threshold of spectral response to the near-infrared region. Furthermore, through repeated Cs/O activation, the cathode sample can possess better stability of operation. The photoelectron spectroscopy measurement results present the changes in the chemical states of surface elements and the corresponding work function after Cs/O activation and degradation. This Cs/O-activated graphene/metal photocathode can provide a new strategy to enhance the photoemission performance and stability of such photocathodes.

Conference Presentation

(2024) Published by SPIE. Downloading of the abstract is permitted for personal use only.

Citation Download Citation

Yijun Zhang, Song Tang, Yu Jiang, Zehao Tong, Shiman Li, Yunsheng Qian, Rongguo Fu, Feng Shi, and Gangcheng Jiao "Improvement of photoemission performance of graphene/metal van der Waals heterojunction photocathode", Proc. SPIE 13015, Photosensitive Materials and their Applications III, 1301514 (18 June 2024); https://doi.org/10.1117/12.3014504

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available