Morphology controlling of manganese-cobalt-sulfide nanoflake arrays using polyvinylpyrrolidone capping agent to enhance the performance of hybrid supercapacitors

Tensangmu Lama Tamang; Saad Gomaa Mohamed; Ganesh Dhakal; Jae-Jin Shim

doi:10.1016/j.jcis.2022.05.103

Morphology controlling of manganese-cobalt-sulfide nanoflake arrays using polyvinylpyrrolidone capping agent to enhance the performance of hybrid supercapacitors

J Colloid Interface Sci. 2022 Oct 15:624:494-504. doi: 10.1016/j.jcis.2022.05.103. Epub 2022 May 21.

Authors

Tensangmu Lama Tamang¹, Saad Gomaa Mohamed², Ganesh Dhakal¹, Jae-Jin Shim³

Affiliations

¹ School of Chemical Engineering, Yeungnam University, 280 Daehak-ro, Gyeongsan, Gyeongbuk 38541, Republic of Korea.
² School of Chemical Engineering, Yeungnam University, 280 Daehak-ro, Gyeongsan, Gyeongbuk 38541, Republic of Korea; Mining and Metallurgy Engineering Department, Tabbin Institute for Metallurgical Studies (TIMS), Tabbin, Helwan 109, Cairo 11421, Egypt.
³ School of Chemical Engineering, Yeungnam University, 280 Daehak-ro, Gyeongsan, Gyeongbuk 38541, Republic of Korea. Electronic address: jjshim@yu.ac.kr.

PMID: 35667211
DOI: 10.1016/j.jcis.2022.05.103

Abstract

Transition metal sulfide-based electrode materials are promising candidates for energy storage applications owing to their richer redox-active sites and higher electrical conductivity than their oxide counterparts. Manganese-cobalt-sulfide (MCS) nanoflakes were synthesized on nickel foam in the presence of polyvinylpyrrolidone (PVP) as a capping agent using a one-step hydrothermal method. The variation in the amount of PVP in the reaction solution had a prominent impact on the MCS electrode morphology. PVP altered the morphology of the MCS nanoflakes. Different shapes of interconnecting-nanoflake arrays were formed with different amounts of PVP. The MCS electrode prepared using 0.2 g of PVP (MCS-P2) showed the best efficiency with a specific capacity of 1312 C g^-1 (3215 F g^-1) at 1 A g^-1 and still retained a remarkable capacity of 1000 C g^-1 (2480 F g^-1) at 20 A g^-1. Moreover, the hybrid supercapacitor (HS) device consisting of MCS-P2//reduced graphene oxide (rGO) revealed a high energy density of 48.7 Wh kg^-1 at a corresponding power density of 386 W kg^-1. Even at a higher power density of 10.8 kW kg^-1, a notable energy density of 25.5 Wh kg^-1 was retained. These remarkable results highlight the potential applications of the MCS-P2 electrode material in energy storage.

Keywords: Capping agent; Hybrid supercapacitor; Manganese-cobalt-sulfide; Nanoflakes; PVP-assisted synthesis.