Functionalization of Graphite Electrodes with Aryl Diazonium Salts for Lithium‐Ion Batteries

Abstract

The functionalization of electrode surfaces is a useful approach to gain a better understanding of solid–electrolyte interphase formation and battery performance in lithium‐ion batteries (LIBs). Electrografting and deprotection of alkyl silyl protected ethynyl aryl diazonium salts on graphite electrodes were performed. Furthermore, electrografting of aryl diazonium salts carrying functional groups such as amino, carboxy and nitro, and their influence on the electrochemical performance in LIBs were investigated. The drawbacks of electrografted and especially deprotected samples were evaluated and compared to corresponding in situ grafted samples. While electrografted samples tend to lower the delithiation capacities, in situ grafted samples, except amino groups, reveal higher capacities. Ethynyl (TMS) shows improved capacities at 1 C and better capacity retention compared to the pristine graphite electrode. Additionally, the Coulombic efficiency of the first cycle was enhanced for in situ grafted samples.

Boosting the Low-Temperature Performance of Graphite Anodes by Creating an Electrochemically Active Interface

“…The grafting of aryl diazonium salts onto the graphite surface has been previously explored as an effective means to enhance electrochemical performance. − These layers can act as a stable and compact artificial solid electrolyte interphase (SEI), providing protection to graphite particles during (de)­lithiation. However, to the best of our knowledge, these layers have rarely been designed as electrochemically active layers to facilitate lithium diffusion on the graphite surface.…”

Crucial interactions of functional pyrenes with graphite in electrodes for lithium‐ion batteries

“…Recently, we observed this trend to be true for functionalization of graphite electrodes with p ‐carboxy and p ‐amino aryl diazonium salts. [ 21 ] In contrast to aryl diazonium modification, the pyrene functional groups are orientated in parallel to the graphite surface. Additionally, we evaluated 1‐pyrenebutyric acid and 1‐pyrenebutylamine, where the functional groups are able to orientate either parallel to the basal plane or the edge site.…”

Covalent grafting of aryls to modulate the electrical properties of phthalocyanine-based heterostructures: Application to ammonia sensing

“…This is manifested by the modifications of a range of surfaces, such as those of carbon [6][7][8], metals [9,10] and semiconductors [11,12] with plethora of aromatic molecules, bearing peripheral functionalities among nitro, amine, thiol, ester, alcohol, alkyl and halogen. Owing to the advantages of performing electrografting directly on the electrode, this method has been exploited in multitude of application areas, such as sensors [13,14], catalysis [15,16], energy conversion and storage [17,18] and molecular electronics [19,20]. Some of these applications sought the growth of a monolayer of organic film, employing different strategies, among which those based on the control of charges consumed [21], use of bulky substituents [22,23] in the precursor aryldiazonium salt and employing radical scavenger [24], are worth mentioning.…”