Dipotassium terephthalate as promising potassium storing anode with DFT calculations. (September 2020)

• Record Type: Journal Article
• Authors: Ghosh, Sourav; Makeev, Maxim A.; Macaggi, Martina Lucia; Qi, Zhimin; Wang, Haiyan; Rajput, Nav Nidhi; Martha, Surendra K.; Pol, Vilas G.
• Is Part Of: Materials today energy. Volume 17(2020)
• Publication Date: 2020-09
• Subjects: Waste PET -- Microwave irradiation -- Organic anode -- K-ion battery -- Density functional theory; Energy development -- Periodicals; Energy industries -- Periodicals; Power resources -- Periodicals; Energy policy -- Periodicals; Energy development; Energy industries; Energy policy; Power resources; Electronic journals; Periodicals; 621.042
• DOI: 10.1016/j.mtener.2020.100454
• Languages: English
• ISSNs: 2468-6069

Abstract

Abstract: We report combined experimental and theoretical studies of dipotassium terephthalate as anode material for K-ion battery application. Both pristine and carbon nanotube-containing dipotassium terephthalate materials are synthesized using an ultrafast microwave-assisted method. We found that carbon nanotube (CNT)-containing dipotassium terephthalate composite electrode delivers an initial reversible capacity of 247 mAh/g with 78% capacity retention, whereas pristine K2 Tp deliveries an initial reversible capacity of 212 mAh/g with 53% capacity retention at the end of 100 cycles, at a current density of 50 mA/g. The density functional theory-based calculations have shown superior stability of dipotassium terephthalate lattice against the intercalation of potassium atoms. The quantum calculations are also employed to unravel the specifics of intercalation energetics of potassium ions into dipotassium terephthalate lattice. The intercalation and de-intercalation potentials of K-ions are obtained using cyclic voltammetry and compared with theoretical calculations under the assumption of a two-electron transfer reaction. The results of this study lay the ground for understanding the electrochemical processes involved in the operation of an organic anode in K-ion batteries, and thereby can facilitate the design of optimal organic molecular crystal-based electrode materials for battery applications. Graphical abstract: Dipotassium terephthalate (K2 Tp) nanosheets are upcycled from waste PET plastic using ultrafast microwave process to study the K-ion storage behavior. Image 1 Highlights: CNT embedded dipotassium terephthalate (K2 Tp) nanosheets are upcycled from PET plastic using microwave process. The inclusive contact between the CNT and K2 Tp nanosheets leads to superior cycling and C-rate behavior. DFT calculations investigate K-ion storage mechanism and its potential bonding sites in K2 Tp.