Recently, Professor Ci Lijie's research group at the School of Materials Science and Materials of Shandong University has made important progress in the research of anode materials for high-performance potassium-ion batteries, and the relevant research results have been published in Energy, an important journal of energy materials, entitled "Hierarchically porous carbon supported Sn4P3as a superior anode material for potassium-ion batteries" Storage Materials (2019, https://doi.org/10.1016/j.ensm.2019.04.037, real-time factor=13.31). The first author of the article is Li Deping, a doctoral student of the class of 2016, Professor Ci Lijie and Associate Professor Si Pengchao of the School of Materials Sciences are co-corresponding authors, and Shandong University is the first author.
In recent years, with the rapid development of portable electronic devices, electric vehicles and large-scale energy storage systems, there is a higher demand for the energy density and power density of energy storage devices. At present, lithium-ion batteries (LIB) are the most widely used, but due to the low crustal reserves of lithium resources (~17ppm) and uneven geographical distribution (~70% distributed in South America), the cost of lithium-ion batteries is increasing year by year, thus limiting its application in large-scale electrical equipment. In contrast, potassium, which is also an alkali metal element, also has similar electrochemical properties to lithium, and its crustal abundance (~15000oon) is much higher than that of lithium. As a result, potassium-ion batteries (PIBs) have attracted widespread attention from researchers. However, the capacity of carbon-based anode materials reported in large quantities is generally not high, but the cycle stability is better, and non-carbon-based materials (such as alloy negative electrodes and phase transition negative electrodes) have high theoretical capacities, but due to the large radius of potassium ions (1.38 Å, lithium ion radius of 0.76 Å), electrode materials will face serious volume expansion during potassium storage, often showing poor magnification properties and short cycle life. Therefore, the construction of carbon-based-non-carbon matrix composites is an effective strategy for the preparation of an anode of high-performance potassium-ion batteries.
Under the guidance of Professor Ci Lijie and Associate Professor Si Pengchao, Li Depingren obtained a Sn4P3@C composite electrode material coated with carbon of multi-stage pore structure by calcination and disalomy citrate as the precursor. When used as a negative electrode material for potassium-ion batteries, the material exhibits excellent potassium storage properties: high reversible capacity, excellent magnification properties and long cycle stability. In addition, the researchers also explored the potassium storage mechanism and excellent electrochemical properties of the Sn4P3@C electrodes by means of GT (constant current batch titration) and non-in situ XRD. This research work provides a learnable way for the development and exploration of large-scale energy storage systems, especially for the research of high-performance electrode materials for alkali metal ion batteries (lithium ion, sodium ion, potassium ion and zinc ion, etc.) has great reference value and guiding significance.
In addition, after the phosphating of tin-based materials, in view of the excellent electrochemical properties of tin disulfide in sodium-ion batteries, under the guidance of Professor Ci Lijie and Associate Professor Si Pengchao, Li Deping tried the preparation of SnS2@C composite materials on the basis of Sn@C composite materials, and it was found that spherical tin particles would grow into flakes in orientation during the vulcanization process, thereby piercing the carbon-coated shell layer, resulting in poor electrochemical properties. Based on this, the researchers designed the graphene surface limiting strategy, successfully achieved morphological regulation and effective carbon coating of SnS2 particles, and exhibited excellent electrochemical properties in sodium-ion batteries and potassium-ion batteries. The relevant research results were published in ChemSusChem (2019, https://doi.org/10.1002/cssc.201900719, impact factor = 7.411).
In recent years, relying on the good research platform of Shandong University and the School of Materials, the Carbon Nanomaterials Research Center of Shandong University-Rice University led by Professor Ci Lijie has made a series of research progress in new energy storage devices. Energy Mater.、Energy Storage Mater.、ACS Nano、Nano Energy、J. Mater. Chem. A、ACS Appl. Mater. Interfaces, Nano Research, ChemSusChem, Nanoscale and other internationally renowned journals have published a number of papers in materials, which have been widely concerned by domestic and foreign counterparts.
Since its establishment, the Shandong University-Rice University Carbon Nanomaterials Research Center has received continuous support from the School of Materials Science and Technology of Shandong University, the Institute of Science and Technology and the International Affairs Department. The above research is also supported by the Shandong Provincial Natural Fund, the Shandong Taishan Scholars Program, the Shandong Provincial Key R&D Program, and the Shandong University Independent Innovation Project.
Article links:
https://doi.org/10.1016/j.ensm.2019.04.037
https://doi.org/10.1002/cssc.201900719
Fig. 1 (a) Schematic diagram of the synthesis process of Sn@C, (b) Sn4P3 and (c) Sn4P3@C
Figure 2 Electrochemical potassium storage performance. (a) CV curve of Sn4P3@C electrode at 0.1 mV s-1 sweep speed; (b) charge and discharge curve of Sn4P3@C electrode at 100 mA g-1 current density; (c) cyclic performance of Sn4P3 and Sn4P3@C electrode at 100 mA g-1 current density; (d) magnification performance of Sn4P3 and Sn4P3@C electrodes; and (e) long cycle stability of Sn4P3@C electrodes at 500 mA g-1 current density.
【 Author:Zhang Jizhi Source:Shandong University】