News Source: School of Materials Science and Engineering

Editor: News Agency of BIT

Translator: Zhao Guangyi, News Agency of BIT

As a new round of energy source revolution draws near, it is essential to vigorously develop power generation using renewable energy and large-scale energy storage, as to achieve industrial transformation and economical sustainable development. Though new energy source industry in our country has boosted in recent years, alternative resources such as wind energy and solar energy are random and uncertain, which can influence the stability of power grid if connected in a larger scale. Electrochemical energy storage is stable, and the lithium-ion battery, with its high energy density, high power density and high working voltage, has become one of the major energy storage devices now. But the lack of lithium source led to a higher cost, which greatly affected its large-scale energy storage. Sodium-ion battery, a rising star in the secondary battery field, is abundant in resource and relatively cheap. Taking into account factors such as its power density, energy density and manufacturing cost, sodium-ion battery is expected to be the best choice in developing large-scale energy storage system application in the future.

Figure 1 large-scale energy storage application of sodium-ion battery& its critical materials

The material of the anode and cathode as well as the electrolyte is the essential components in sodium-ion battery, which is also crucial for its chemical properties. Many types of anode materials are under research, including layered metallic oxide, polyanion, prussian blue and organic materials, while cathode materials include transition materials, alloy and carbon materials. For electrolytes, there are solid, organic and hydro ones. Different electrolytes require different cathode and anode materials.

Recently, one of the international material journals, Advanced Functional Materials (IF 16.836) covered BIT’s progress in the anode of sodium-ion battery by the research group led by professor Chen Renjie and vice-professor Xie Man from School of Materials Science and Engineering. The achievements were published online with the title “Fe₂VO₄Nanoparticles Anchored on Ordered Mesoporous Carbon with Pseudocapacitive Behaviors for Efficient Sodium Storage”. Doctor Jiang Ying is the first author, and vice-professor Xie Man and professor Chen Renjie are the corresponding authors.

Figure 2 The synthetic process of Fe2VO4@CMK-3 composites

Compared with monometallic oxide, bimetallic oxides perform better at electrical/ionic conductivity and electrochemical activity in alkali metal ion storage. Fe₂VO₄is rich in raw materials and of theoretically high specific capacity, and therefore has attracted widespread attention as an cathode material in sodium-ion battery. However, Fe₂VO₄particles agglomerate easily, which leads to unsatisfactory cycling performance and a rapid capacity fade. To address this problem, Fe₂VO₄@CMK‐3 composites were synthesized through hydrothermal reaction and subsequent calcination. This material has multiple advantages. As the carbon scaffold, ordered mesoporous CMK-3 significantly improves the electrical conductivity. Fe₂VO₄nanoparticles scattered on the CMK‐3 scaffold, which provides abundant active surfaces. Additionally, nano-composite structure provide sufficient volume expansion buffer space during cycling. Therefore, the Fe₂VO₄@CMK‐3 composites exhibit an excellent cycling performance when applied to anode material in sodium-ion batteries. The Fe₂VO₄@CMK‐3 also shows a high pseudocapacitance contribution ratio, reaching a capacitance contribution of 89.1% at a sweep rate of 1.0 mV s⁻¹, which enables a high rate performance. Moreover, Sodium-ion full cells with NaNi1/3Fe1/3Mn1/3O2 cathodes and Fe₂VO₄@CMK‐3 anodes exhibit stable cycle performance, whose capacity retention remains 81% after 500 cycles at 0.5 A g-1. The research provides a new idea for the studies in cathode material in sodium-ion battery and the construction of nano-composite materials.

Figure 3 Fe2VO4@CMK-3 full cell construction and its electrochemical capability

Link to the article: Fe₂VO₄Nanoparticles Anchored on Ordered Mesoporous Carbon with Pseudocapacitive Behaviors for Efficient Sodium Storage. Adv. Funct. Mater. 2021, 2009756. https://doi.org/10.1002/adfm.202009756

Link to the paper: Fe₂VO₄Nanoparticles Anchored on Ordered Mesoporous Carbon with Pseudocapacitive Behaviors for Efficient Sodium Storage. Adv. Funct. Mater. 2021, 2009756. https://doi.org/10.1002/adfm.202009756

With the support of academician Wu Feng and National Key R&D Program of China (Research on basic scientific issues of high safety, long life and low-cost sodium-based energy storage batteries, 2016YFB0901500), the sodium-ion battery research group carried out systematic studies in the field of key materials of sodium-ion battery. In the past three years, in terms of cathode materials, different types of materials including high-quality Prussian blue and Manganese based P2 phase cathodes have been synthesized by optimizing synthesis process, structural design and regulation, as well as precise ion exchange. In terms of anode materials, anode materials with fast reaction rate, stable interface and small volume expansion were synthesized by various design methods such as structural regulation, heterogeneous structure design and dynamical optimization. The group participated in the College Material Innovation Competition, the Century Cup, the Challenge Cup and the China College Students' ‘Internet+' Innovation and Entrepreneurship Competition, and won the 6th internet+ I&E Competition with gold award, as well as the first prize of the 2020 Excellent Entrepreneurial Team in Beijing, and other prizes.

About the authors：

Jiang Ying, a doctoral candidate from class of 2019 majoring in Materials Science and Engineering, BIT, tutored by Academician Wu Feng. Her main academic interest lies in electrode materials in sodium-ion batteries. She published two SCI papers on journals such as Advanced Functional Materials and Journal of Materials Chemistry A. She participated in the 6th internet+ I&E Competition and won the second award in Beijing as the project leader. She also participated multiple times in the Challenge Cup and the Century Cup.

Xie Man, Associate Professor, mainly engages in new energy source and the development and application of Green secondary batteries. Her key research area is the development of lithium-ion battery, sodium-ion battery and aqueous battery system, as well as studies on key materials of the batteries mentioned above. At present, as the program leader, she is responsible for the research The Basic Scientific Issues of High Safety, Long Life and Low Cost Sodium-based Energy Storage Batteries in the National Key R & D Program Project. She participated in the National Basic Research Program of China (973 Program), Chinese National Programs for High Technology Research and Development (863 Program) and other significant programs as a key member. She also won a first prize of science and technology at provincial level, and published an academic monograph and over 40 academic essays on international journals such as Advanced Science, Nano Energy and Small. Xie man was awarded about 10 national invention patents, and selected in Science and technology Talent Entrepreneurship Plan of Beijing and Zhenjiang city, and was funded by the government financially as well as enjoying policy support. As a coach, she guided her students to participate in the science and technology innovation and entrepreneurship competition and won a national gold medal and many other provincial awards, including the first prize of excellent entrepreneurial team in Beijing.

Chen Renjie, professor and doctoral tutor, member of the Energy Professional Group of National Ministries and Commissions, the director of Chinese Materials Research Society (C-MRS), Secretary General of Energy Conversion and Storage Materials Branch, director of the Chinese Society of Solid Ionics, director of the International Academy of Electrochemical Energy Sciences (IAOEES), member of the New Chemical Material Department of CIESC and an expert in the national battery industry of the China Battery Industry Association (CBIA). He mainly engages in the teaching and research work in multi-electron high specific energy secondary battery new system and key materials, new ionic liquids and multi-functional electrolyte materials, new film materials and structural devices for special power supply, as well as green secondary battery recycling. He led several researches of National Key R&D Program of China, 863 program, Major achievements transformation project of Central University in Beijing and Beijing Science and technology project. Professor Chen has also published over 200 SCI essays on journals such as Chemical Reviews, Chemical Society Reviews, National Science Reviews, Advanced Materials, Nature Communications, Angewandte Chemie-International Edition, Advanced Functional Materials and Energy Storage Materials. He applied for 96 patents and received 42, and was awarded 10 software copyrights. He published 2 academic monographs (Advanced battery functional electrolyte materials, Science Publisher, 2020, book number ISBN 978-7-03-060718-8 and Multi-electron and High Specific Energy Lithium-Sulphur Secondary Battery, Science Publisher, 2020, book number ISBN 978-7-03-060718-8). He won a national technology invention second prize and four ministerial invention first prizes, and was selected as the distinguished professor of Changjiang Scholar, Outstanding Young Scientists of Beijing advanced universities, Outstanding young scholars of Chinese engineering frontier, committee of RSC and the global highly-cited scientist of Clarivate Analytics 2020.