I deposit graphene films on glass/quartz substrates of the size 2cm (20 millimeters) by spray method. Spray is fixed and at a distance of around 13 cm from substrate.
Graphene is dispersed in ethanol or CHCL3 before deposition and substrate is placed on hot plate at 100 to 125°C before and during deposition.
The films of graphene that I get are of several 100s on nm thick with variotions but there are some peaks which could be as high as 1 to 2 micrometers.
1. I want to control the roughness: say a film of 300 nm with accptable roughness of 20 nm.
Is there another method of deposition which could be suitable in my case? sputtering, cvd, epitaxy are not in option. Some cheaper method is sought! Spin-coating was tried also but it was not good either due to roughness or other factors i might not know!
OR
2. Is there any method to polish the surface of film to improve the surface and remove big mountains above few hundreds of nm. I mean a nano-polisher? physical contact/non-contact method?
3. Can I coat the graphene film with some other material like a thin film of PEDOT:PSS, (to protect the graphene film) say 40 nm thick and do poilshing over PEDOT:PSS to remove the rough mountains? Iam not sure for this as PEDOT:PSS is good with water and graphene is well-dispersed in ethanol!
I am looking for the suggestions on any step/solvent/deposition method in my process.
Thanks in advance!
Roughness may be related to the quality of your substrate surface and your cleaning procedure of the substrate. Check these factors first before looking for other technique. Good luck
Two problems with your technique.. as Prof. Boufelfel pointed out, the substrate may not be smooth enough. Second, you are heating the sample to 100-125C.. this may cause evaporation of solvent intercalated in the interstatial layers.. so you are seeing extensive wrinkling.. one option is using annealing at higher temperatures preferably in vaccum.
Other technique to obtain graphene thin films is by using liquid-liquid interface approach. see this paper: http://pubs.acs.org/doi/pdf/10.1021/nl802724f
1 What is this CHCl3 doing in your spray solvent?
2 is that EHD spray you mentioned?
Can you give the details of quartz substrates for graphene films.
I mean what type of quartz substrates are used.
- Badges
- Science topic
- Similar topics
- Physical Sciences
- Materials Science
- Materials
- Carbon Materials
- Graphite
- Graphene