In-situ magnetization measurements and ex-situ morphological analysis of electrodeposited cobalt onto chemical vapor deposition graphene/SiO₂/Si

• 영문명: In-situ magnetization measurements and ex-situ morphological analysis of electrodeposited cobalt onto chemical vapor deposition graphene/SiO₂/Si
• 발행기관: 한국탄소학회
• 저자명: Vin？cius C. De Franco Gustavo M. B. Castro Jeaneth Corredor Daniel Mendes Jo？o E. Schmidt
• 간행물 정보: 『Carbon Letters』제21권, 16~22쪽, 전체 7쪽
• 주제분류: 자연과학 > 자연과학일반
• 파일형태: PDF
• 발행일자: 2017.01.01

영문 초록

Cobalt was electrodeposited onto chemical vapor deposition (CVD) graphene/Si/SiO2 substrates, during different time intervals, using an electrolyte solution containing a low concentration of cobalt sulfate. The intention was to investigate the details of the deposition process (and the dissolution process) and the resulting magnetic properties of the Co deposits on graphene. During and after electrodeposition, in-situ magnetic measurements were performed using an (AGFM). These were followed by ex situ morphological analysis of the samples with ΔtDEP 30 and 100 s by atomic force microscopy in the non-contact mode on pristine CVD graphene/SiO2/Si. We demonstrate that it is possible to electrodeposit Co onto graphene, and that in-situ magnetic measurements can also help in understanding details of the deposition process itself. The results show that the Co deposits are ferromagnetic with decreasing coercivity (HC) and demonstrate increasing magnetization on saturation (MSAT) and electric signal proportional to remanence (Mr), as a function of the amount of the electrodeposited Co. It was also found that, after the end of the dissolution process, a certain amount of cobalt remains on the graphene in oxide form (this was confirmed by X-ray photoelectron spectroscopy), as suggested by the magnetic measurements. This oxide tends to exhibit a limited asymptotic amount when cycling through the deposition/dissolution process for increasing deposition times, possibly indicating that the oxidation process is similar to the graphene surface chemistry.

목차

1. Introduction

2. Experimental

3. Results and Discussion

4. Conclusions

References

키워드

cobalt electrodeposition in situ magnetization measurements CVD graphene/SiO₂/Si