Freestanding WS<sub>2</sub>-MWCNT Nanocomposite for Electrochemical Detection of Contaminants of Emerging Concern─Perfluorooctanoic Acid “A Forever Chemical” and Supercapacitor Applications
Fouzia Mashkoor, Rushda Mashkoor, Mohd Shoeb, Abdul Hakeem Anwer, Hongjun Jeong, Changyoon Jeong
Abstract
Perfluorooctanoic acid (PFOA) presents a significant environmental challenge due to its persistent nature and resistance to degradation. Our research offers an innovative solution by an ingenious combination of WS 2 and multiwalled carbon nanotubes (MWCNTs) to synthesize a versatile, freestanding WS 2 -MWCNT electrode for electrochemical sensing of PFOA and as a supercapacitor device. This electrode demonstrated outstanding electrochemical sensing capabilities, exhibiting a detection limit of 2.404 pM for PFOA. The interference study revealed that the electrode has a high degree of selectivity toward PFOA. Real-world applicability was assessed through testing tap water and various food samples, yielding recovery rates within 96.53–102.11%, underscoring the viability of the WS 2 -MWCNT electrode in practical applications. Furthermore, the WS 2 -MWCNT displayed excellent supercapacitor performance. The fabricated device displayed a specific capacitance of 134.72 F/g at a current density of 6 A/g and showcased a high energy density of 46.15 Wh/kg at a power density of 500 W/kg. Furthermore, the WS 2 -MWCNT exhibited good durability, with a capacitance retention rate of 89.14% even after undergoing 10 000 cycles.These findings highlight the multifunctional electrochemical applications of the WS 2 -MWCNT NCs, attributed to the synergistic impact of WS 2 and MWCNTs to achieve suitable specific capacitance and susceptible detection of forever chemicals.