Activated Carbon‐Anchored 3D Carbon Network for Bromine Activity and its Enhanced Electrochemical Performance in Zn−Br₂ Hybrid Redox Flow Battery

Abstract

There has been a huge demand on the usage of biomass‐derived activated carbon as an electrode and electrocatalyst for energy storage and conversion applications owing to its abundance, high surface area, good chemical stability, low cost, and eco‐friendliness. Herein, we report for the first time, activated carbon (AC) derived from Phyllanthus Emblica Leaves (PEL) (Indian gooseberry) biomass as an electrocatalyst for enhancing the bromine electro‐kinetics. The AC‐anchored graphite felt (AC−GF) showed excellent improvement in the bromine reversibility, which reinforces the overall performance of the zinc bromine redox flow battery (ZBRFB). Specifically, the AC−GF showed significant improvement in voltage efficiency. The flow cell employing AC in the positive electrode showed high Coulombic, voltage, and energy efficiency of 99, 83 and 82 %, respectively at a current density of 30 mA cm−2. Furthermore, the cell showed good cycle performance with 96.43 % Coulombic efficiency retention even after 100 cycles. Thus, the significant improvement in the cell performance unveils the good electrochemical/catalytic activity of the AC and therefore can be used as a potential low‐cost electrocatalyst in ZBRFB.

Carbon Nanotube Scaffolds Entrapped in a Gel Matrix for Realizing the Improved Cycle Life of Zinc Bromine Redox Flow Batteries

“…The independent operation of energy and power provides a better pathway for storing energy on a large scale sustainably. The RFBs can be classified based on the redox couples adopted in the system such as zinc/bromine, , all-vanadium, , all-iron, , zinc/vanadium, iron/chromium, etc. Among various RFBs, zinc/bromine and all-vanadium RFBs are well-matured systems and commercialized around the world.…”

Exploring Contemporary Advancements and Outlook in Viologen-Based Aqueous Organic Redox Flow Batteries: A Mini Review

“…The AORFBs and NAORFBs have materialized as viable alternatives to classic aqueous inorganic RFBs (AIRFBs). , AIRFBs are potentially safe and cost-effective grid-scale storage devices. A variety of AIRFBs were linked, including iron–titanium, iron–vanadium all vanadium, polysulfide–bromine, and zinc–bromine and zinc–iron systems. All vanadium RFBs (AVRFBs) and iron chromium systems were successfully proven at the commercial scale among these AIRFBs .…”

Electrochemical energy storage and conversion: An overview

“…The utilization of activated carbon‐anchored 3D network toward Br − /Br 2 redox couple has made significant impact on the performance of the ZBB (Pandiyan Naresh et al, 2019). Further, activated carbon‐anchored 3D structures exhibits a two‐fold lower voltage drop (198 mV) compared to that of pristine GF indicating the good interfacial contact between the AC and GF with the supporting electrode and the existence of carboxylic and hydroxyl functional groups when compared with the commercial AC (cAC).…”