Xuanhui Qu’s group at the Institute for Advanced Materials and Technology, University of Science and Technology Beijing recently published an article in

Xuanhui Qu’s group at the Institute for Advanced Materials and Technology, University of Science and Technology Beijing recently published an article in Energy & Environmental Science (IF = 30.067) titled “Zero-strain K_0.6Mn₁F_2.7 hollow nanocubes for ultrastable potassium ion storage” (DOI: 10.1039/C8EE01611A), which reported a new route toward the synthesis of uniform-sized hollow KMnF-NCs, utilizing a controlled etching reaction time for generating structural defects and vacancies within the crystal. Owing to the existence of K and F vacancies, this special structure can accommodate a volume expansion resulting from the intercalation of potassium ions, thereby boosting the KIBs in terms of capacity, rate ability, and stability. Moreover, the study demonstrated that the crystal structure and defects in KMnF-NCs have an important influence on the etching reaction. During the reversible charge and discharge processes, hollow nanocube frameworks with nanoporous shells provide a highly specific surface area and pseudocapacitance characteristics, endowing the material with a high capacity, stability, and good rate performance. Even at a very high current density of 400 mA·g⁻¹, the capacity can still retain 110 mAh·g⁻¹ over 10 000 cycles with a high capacity retention of 99%. Moreover, the in situ XRD and DFT calculations prove that the etched KMnF-NCs exhibit a negligible volume change during K ion intercalation and deintercalation, making it a new zero-strain negative electrode material for KIBs with excellent cycling stability. Dr. Zhiwei Liu and professor Ping Li from the University of Science and Technology Beijing are the co-first authors of the paper, whereas Dr. Wei Wang from Peking University is a co-corresponding author.

The group headed by professor Xuanhui Qu has long engaged in investigations on the preparation of special powder materials and powder metallurgy for near net shape technology. In recent years, under the leadership of professors Xuanhui Qu, Mingli Qin, and Ping Li, the group has dedicated itself to the application of new powder material technologies for refractory metals, soft magnetic alloys, aluminum nitride with a high thermal conductivity, lithium- and potassium-ion electrode materials, fuel cell catalysts, and other new materials. The development of subspherical micro(nano) tungsten powder, iron powder, and aluminum nitride ceramic powder satisfying the technical standards for powder injection molding has realized a precise near net shaping using these intractable materials. Related products have found application in both national defense and civilian areas. The achievements have resulted in forty national invention patents, first prize of the Technological Invention Award from the Ministry of Education (2011), and two first prizes of the Science and Technology Invention Award of China Nonferrous Metals Industry (2016 and 2017).

Since 2016, the group has been designing a series of novel electrode materials, significantly improving the cycle capacity and stability of lithium- and potassium-ion batteries. Furthermore, to reduce the use of noble metal catalysts during catalysis, the idea of attaching catalytic noble metal nanocrystals to the surface of catalytic base metals has been proposed. Based on these new materials, the group has explored their application in capacitors, the electrolysis of water for hydrogen and oxygen gases, and wave-absorbing materials. A series of innovative results have been published in internationally renowned journals such as Adv. Funct Mater, 2018 (accepted); Energy Storage Mater, 2018, 10, 268. J. Mater. Chem. A, 2018, 6, 11147; J. Mater. Chem. A, 2018, 6, 7053; ACS Appl. Mater. Inter, 2016, 8, 15582; ACS Appl. Mater. Inter, 2016, 8, 25954, Chem. Commun, 2017, 53, 2922.