Abstract:

Multiple metal selenides (MMSs) have drawn pronounced attraction as promising anodes for sodium ion batteries (SIBs) owing to their greatly enhanced electrochemical performances originating from the superior intrinsic conductivities and richer redox sites, compared to single-metal chalcogenides. Moreover, the use of binder in electrode manufacturing not only causes dead weight inclusion, but also reduces the exposed surface area of active material. Hence, high surface area bearing and hierarchical nanostructures of iron-cobalt selenide (FCSe) and iron-nickel selenide (FNSe) were deposited over carbon fiber cloth (termed as FCSe/CFs and FNSe/CFs, respectively) and employed directly as anodes of SIBs. Carbon fiber cores not only act as intimate current collecting conductive highways for electron transport but also provide strength needed for self-standing electrode of battery. A simple and scalable hydrothermal strategy was employed with to prepare nanowire or nanosphere like morphologies of precursors were prepared under different conditions which were then selenized under optimized conditions to obtain corresponding MMSs. When employed in SIBs, FCSe/CFs and FNSe/CFs exhibited adequately high energy capacities and appreciable rate capabilities. In addition to this, FCSe/CFs and FNSe/CFs electrodes also presented extraordinary stable life of over 200 cycles. Structure robustness of cycled electrodes was also evaluated via ex-situ X-ray diffraction and various microscopic analysis techniques. We are confident that the presented strategy will pave the way for facile synthesis of a large family of MMSs with carbon fiber hybrids which are the potential materials for energy storage and conversion systems.

Subject Field of Topic: Materials engineering

Name of Speaker: Dr Zeeshan Ali

Professorial Rank of Speaker: Assistant professor

University Email of Speaker: [email protected]

Research Group Weblink or University Profile weblink: https://scme.nust.edu.pk/research/faculty-me/
Affiliation of Speaker: School of Chemical and Materials Engineering (SCME), National University of Sciences and Technology (NUST)