Byatarayappa Gopalakrishna, G Radhika M, R Srilakshmi, V Tejashree, Venkatesh Krishna, N Nagaraju, Nagaraju Kathyayini
Centre for Incubation Innovation Research and Consultancy (CIIRC), Jyothy Institute of Technology, Tataguni, off Kanakapura Road, Bengaluru, 560082, Karnataka, India.
Department of Physics, R.V. College of Engineering, Bengaluru, 560059, Karnataka, India.
Heliyon. 2023 Apr 18;9(4):e15399. doi: 10.1016/j.heliyon.2023.e15399. eCollection 2023 Apr.
In the present scenario of research, the recycling of inexpensive widely available agricultural waste/biowaste to activate carbon (AC) and procurement of value-added product has significant impact on energy storage systems, particularly in Electrochemical double layer capacitors (EDLCs). Herein, we report the production of KOH activated carbons from different biomass sources such as stem (MAC), seed oil extract cake (PPC), stem (CCC) and floss (ASC) for the said purpose. Initially, the biomass materials were pyrolyzed at 550 °C and then activated with KOH at 800 °C. All the carbon materials were characterized for their physico-chemical properties by various analytical techniques and compared. Further, these materials were studied for their electrochemical performance using suitable electro-analytical techniques in 1 M KOH solution. ACs (Activated carbons) derived from MAC, PPC, CCC & ASC were estimated in three electrode system and were found to exhibit a specific capacitance (Cs) of 358, 343, 355 & 540 F/g at a scan rate of 2 mV/s and 102, 188, 253 & 256 F/g at a current density of 2.5 A/g respectively. The main novel objective of this work is to correlate the morphological and surface properties of these ACs obtained from different biomass sources with electrochemical performance. A symmetric coin cell constructed with ASC material exhibited Cs of 67 F/g at a current density of 2.5 A/g with maximum energy & power densities (ED & PD) of 37.2 W h/kg and 19.9 kW/kg respectively. Further the cell showed 25,000 cycles stability with 86% Cs retention and 100% coulombic efficiency.
在当前的研究背景下，将廉价且广泛可得的农业废弃物/生物废弃物回收利用以制备活性炭（AC）并获得增值产品，对储能系统具有重大影响，尤其是在电化学双层电容器（EDLC）方面。在此，我们报告了为上述目的从不同生物质来源（如茎（MAC）、种子油提取饼（PPC）、茎（CCC）和绒毛（ASC））制备氢氧化钾活化碳的过程。首先，将生物质材料在550℃下热解，然后在800℃下用氢氧化钾活化。通过各种分析技术对所有碳材料的物理化学性质进行了表征并进行了比较。此外，使用合适的电分析技术在1M氢氧化钾溶液中研究了这些材料的电化学性能。在三电极系统中对源自MAC、PPC、CCC和ASC的活性炭（AC）进行了评估，发现在扫描速率为2mV/s时，其比电容（Cs）分别为358、343、355和540F/g，在电流密度为2.5A/g时，比电容分别为102、188、253和256F/g。这项工作的主要新颖目标是将从不同生物质来源获得的这些活性炭的形态和表面性质与电化学性能相关联。用ASC材料构建的对称硬币电池在电流密度为2.5A/g时，比电容为67F/g，最大能量密度和功率密度（ED和PD）分别为37.2W h/kg和19.9kW/kg。此外，该电池在25000次循环中表现出稳定性，比电容保持率为86%，库仑效率为100%。
