Nolly Christopher, Ikpo Chinwe O, Ndipingwi Miranda M, Ekwere Precious, Iwuoha Emmanuel I
Sensor Laboratories (SensorLab), Department of Chemistry, University of the Western Cape, Robert Sobukwe Road, Bellville, Cape Town 7535, South Africa.
Nanomaterials (Basel). 2022 Oct 8;12(19):3514. doi: 10.3390/nano12193514.
Spinel copper manganese oxide nanoparticles combined with acid-treated multi-walled carbon nanotubes (CuMnO/MWCNTs) were used in the development of electrodes for pseudocapacitor applications. The CuMnO/MWCNTs preparation involved initial synthesis of MnO and CuMnO precursors followed by an energy efficient reflux growth method for the CuMnO/MWCNTs. The CuMnO/MWCNTs in a three-electrode cell assembly and in 3 M LiOH aqueous electrolyte exhibited a specific capacitance of 1652.91 F g at 0.5 A g current load. Similar investigation in 3 M KOH aqueous electrolyte delivered a specific capacitance of 653.41 F g at 0.5 A g current load. Stability studies showed that after 6000 cycles, the CuMnO/MWCNTs electrode exhibited a higher capacitance retention (88%) in LiOH than in KOH (64%). The higher capacitance retention and cycling stability with a Coulombic efficiency of 99.6% observed in the LiOH is an indication of a better charge storage behaviour in this electrolyte than in the KOH electrolyte with a Coulombic efficiency of 97.3%. This superior performance in the LiOH electrolyte than in the KOH electrolyte is attributed to an intercalation/de-intercalation mechanism which occurs more easily in the LiOH electrolyte than in the KOH electrolyte.
尖晶石型铜锰氧化物纳米颗粒与酸处理的多壁碳纳米管（CuMnO/MWCNTs）相结合，用于开发赝电容器应用的电极。CuMnO/MWCNTs的制备过程包括MnO和CuMnO前驱体的初始合成，然后采用节能回流生长法制备CuMnO/MWCNTs。在三电极电池组件和3 M LiOH水溶液电解质中，CuMnO/MWCNTs在0.5 A g电流负载下的比电容为1652.91 F g。在3 M KOH水溶液电解质中进行的类似研究在0.5 A g电流负载下的比电容为653.41 F g。稳定性研究表明，经过6000次循环后，CuMnO/MWCNTs电极在LiOH中的电容保持率（88%）高于在KOH中的电容保持率（64%）。在LiOH中观察到的较高电容保持率和循环稳定性以及99.6%的库仑效率表明，与库仑效率为97.3%的KOH电解质相比，该电解质具有更好的电荷存储行为。LiOH电解质中的这种优越性能优于KOH电解质，这归因于嵌入/脱嵌机制，该机制在LiOH电解质中比在KOH电解质中更容易发生。
