Interplay of Porosity, Wettability, and Redox Activity as Determining Factors for Lithium–Organic Electrochemical Energy Storage Using Biomolecules

Abstract

Although several recent publications describe cathodes for electrochemical energy storage materials made from regrown biomass in aqueous electrolytes, their transfer to lithium–organic batteries is challenging. To gain a deeper understanding, we investigate the influences on charge storage in model systems based on biomass‐derived, redox‐active compounds and comparable structures. Hybrid materials from these model polymers and porous carbon are compared to determine precisely the causes of exceptional capacity in lithium–organic systems. Besides redox activity, particularly, wettability influences capacity of the composites greatly. Furthermore, in addition to biomass‐derived molecules with catechol functionalities, which are described commonly as redox‐active species in lithium–bio‐organic systems, we further describe guaiacol groups as a promising alternative for the first time and compare the performance of the respective compounds.

Quantifying how step-wise fluorination tunes local solute hydrophobicity, hydration shell thermodynamics and the quantum mechanical contributions of solute–water interactions

“…Tuning hydrophobicity by manipulating hydrogen bonds has been a longstanding goal and challenge in materials science, [8][9][10][11][12][13] organic chemistry [14][15][16] and supramolecular chemistry. [17][18][19][20] However, the usual strategies employed to modify hydrogen bond patterns (the simplest being methylation and hydroxylation) also result in changes in molecular surface area and topology, meaning that water-solute and water-water hydrogen bonds are simultaneously affected.…”

Sustainable Cathodes for Lithium‐Ion Energy Storage Devices Based on Tannic Acid—Toward Ecofriendly Energy Storage

“…[ 14 ] Later, redox reactivity of catecholic groups was confirmed in lithium‐organic electrolytes, suggesting the equivalent redox couple. [ 15 ] Similar mechanism was suggested for tannic acid, ester of glucose and multiple gallic acids, [ 16 ] that is rich with catecholic groups. [ 17,18 ] The good solubility of tannic acid in water and polar organic solvents of low toxicity, such as ethanol, allows for the easy extraction from plant‐based waste such as wood bark.…”

“…The average redox potential is 3.4 V (vs Li/Li + ), which is relatively high compared to conventional organic materials [ 10 ] and outstanding when compared to other electrodes from waste biomass, [ 30 ] although similar to other cathodes utilizing catecholic groups (Table S3, Supporting Information). [ 15,31,32 ]…”

Sustainable Battery Materials from Biomass

“…Importantly, the combination of redox‐active biopolymers and carbon materials results in synergistic enhancement of capacitive and battery‐like charge storage and is not merely a combination of the two. Such synergistic effects may be explained by changes in the carbon's hydrophilicity upon incorporation of biopolymers, facilitating interactions with polar electrolytes and thus resulting in enhanced double layer formation, similar to other charge storage materials . Furthermore, the choice of carbon plays a major role for performance.…”

“…Stability may instead be enhanced by crosslinking . Still, choice of the right binder may also result in enhanced interaction with the active material or electrolyte due to functionalities or changes in the electrode's polarity, respectively, and hence also increase the specific capacity . Additionally, hydrophilicity of the binder material often facilitates ion mobility, permitting higher charge–discharge rates.…”