Research Institute of Highland Forestry, Chinese Academy of Forestry, Kunming, People's Republic of China.
Faculty of Chemical Engineering and Technology, Kunming University of Science and Technology, Kunming, People's Republic of China.
Environ Technol. 2024 May;45(13):2486-2492. doi: 10.1080/09593330.2023.2176790. Epub 2023 Feb 20.
Lithium cobalt oxide (LCO) has been employed as cathode material for 40 years. However, the low solubility of LCOs in water and strong electrostatic force and H-bonding between the LCOs particles limited the use of the aqueous binders in the LCO system. We report a feasible and universal approach to fabricating a complex cathode of LCO and reduced graphene oxide (RGO). Tannic acid (TA) could simultaneously disperse LCO and RGO particles. Meanwhile, the branched polyphenol TA acts as a 'bridge' molecule for connecting the LCO and RGO, confirmed by the SEM test. The rheology properties of the PVDF slurry of cathode materials (LCO, LCO/, RGO, and TA/LCO/RGO) were also determined. It could be found that the TA could act as a crosslinking agent for the LCO and RGO particles, increasing the viscosity and storage modulus of the slurry. The cell employed the TA/LCO/RGO slurry as the cathode material, have a higher areal capacity, and had a higher redox potential than employed LCO/RGO and LCO as cathode materials, all of which could be attributed to the addition of the TA. This green molecule can be used to fabricate environmentally friendly and possibly biodegradable electrochemical energy storage devices.
钴酸锂（LCO）已被用作阴极材料 40 年。然而，LCO 在水中的低溶解度以及 LCO 颗粒之间的强静电力和 H 键合限制了水基粘结剂在 LCO 体系中的应用。我们报告了一种制造 LCO 和还原氧化石墨烯（RGO）复杂阴极的可行且通用的方法。单宁酸（TA）可以同时分散 LCO 和 RGO 颗粒。同时，支化多酚 TA 作为连接 LCO 和 RGO 的“桥”分子，这一点通过 SEM 测试得到了证实。还确定了阴极材料（LCO、LCO/、RGO 和 TA/LCO/RGO）的 PVDF 浆料的流变性能。可以发现，TA 可以作为 LCO 和 RGO 颗粒的交联剂，增加浆料的粘度和储能模量。该电池采用 TA/LCO/RGO 浆料作为阴极材料，具有更高的面容量，并且具有比采用 LCO/RGO 和 LCO 作为阴极材料更高的氧化还原电位，这都归因于 TA 的添加。这种绿色分子可用于制造环保且可能可生物降解的电化学储能器件。
