Journal
NANO LETTERS
Volume 15, Issue 11, Pages 7671-7677Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acs.nanolett.5b03667
Keywords
Potassium ions intercalation; batteries; graphitic materials; first-principles; band structure modulation
Categories
Funding
- NSF-CBET [1335944, 1335979]
- NSF [ACI-1053575]
- Directorate For Engineering
- Div Of Chem, Bioeng, Env, & Transp Sys [1335979] Funding Source: National Science Foundation
- Directorate For Engineering
- Div Of Chem, Bioeng, Env, & Transp Sys [1335944] Funding Source: National Science Foundation
- Directorate For Engineering
- Div Of Civil, Mechanical, & Manufact Inn [1300361] Funding Source: National Science Foundation
Ask authors/readers for more resources
Graphite intercalation compounds (GICs) have attracted tremendous attention due to their exceptional properties that can be finely tuned by controlling the intercalation species and concentrations. Here, we report for the first time that potassium (K) ions can electrochemically intercalate into graphitic materials, such as graphite and reduced graphene oxide (RGO) at ambient temperature and pressure. Our experiments reveal that graphite can deliver a reversible capacity of 207 mAh/g. Combining experiments with ab initio calculations, we propose a three-step staging process during the intercalation of K ions into graphite: C --> KC24 (Stage III) --> KC16 (Stage II) --> KC8 (Stage I). Moreover, we find that K ions can also intercalate into RGO film with even higher reversible capacity (222 mAh/g). We also show that K ions intercalation can effectively increase the optical transparence of the RGO film from 29.0% to 84.3%. First-principles calculations suggest that this trend is attributed to a decreased absorbance produced by K ions intercalation. Our results open opportunities for novel nonaqueous K-ion based electrochemical battery technologies and optical applications.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available