Authors: Nobuhiro Ogihara | Masaki Hasegawa | Hitoshi Kumagai | Riho Mikita | Naoyuki Nagasako
Source: ECS Meeting Abstracts (article, 2024-11-22)
Field: Chemistry — Inorganic Chemistry

(Invited) Heterogeneous Intercalated Metal-Organic Frameworks for Fast-Charging Electrodes Significant progress has been made in recent years with metal-organic frameworks (MOFs) being used as electrode materials for energy storage devices. 1, 2 These frameworks comprise organic molecules and metal ions that form self-assembled structures. Intercalated MOFs (iMOFs) based on aromatic dicarboxylate are particularly appealing as negative electrode active materials for Li-based batteries 3, 4 and capacitors. 5, 6 Such iMOFs store Li ions at approximately 0.8 V vs . Li/Li + and hence avoid Li metal plating during cell operation. The conductive mechanisms 7 and phase transition reactions 8 have been investigated, and the relationship between these properties and structural factors has been clarified. Our proposal involves using machine learning 9 to synthesize iMOFs with multi-aromatic units via solution spray drying, 10 resulting in fast-charging electrodes (Fig. 1). 11 The naphthalene-based multivariate material has been proposed, which has a nanometric thickness and allows for reversible storage of Li-ions in a non-aqueous Li metal cell configuration. This active material can retain up to 85% of its capacity at a discharge rate of 400 mA g −1 , which means that it takes only 30 minutes to fully charge at 20°C, compared to 10 hours for a full charge when cycling at 20 mA g −1 . When this material was tested as negative electrode with an activated carbon-based positive electrode, it showed a discharge capacity retention of about 91% after 1000 cycles at 0.15 mA cm −2 , which takes 2 hours for a full charge at 20°C. It also exhibited improved high-temperature stability at 60°C. Through our research, we have analyzed the changes in the XRD patterns and confirmed the vibration modes by Raman spectra and first-principles phonon calculations during Li intercalation. As a result, we have discovered that samples with fast charging performance have a distorted structure that restrains the bending vibration perpendicular to the naphthalene plane. This structure promotes the delocalization of electrons within the crystal, leading to a phase transition that suppresses phase separation. Consequently, the electrode shows better performance during fast charging. References Z. Liang, C. Qu, W. Guo, R. Zou and Q. Xu, Adv. Mater. , 30 , 1702891 (2018). P. Poizot, J. Gaubicher, S. Renault, L. Dubois, Y. Liang and Y. Yao, Chem. Rev. , 120 , 6490-6557 (2020). N. Ogihara, T. Yasuda, Y. Kishida, T. Ohsuna, K. Miyamoto and N. Ohba, Angew. Chem. Int. Ed. Engl. , 53 , 11467-11472 (2014). T. Yasuda and N. Ogihara, Chem. Commun. , 50 , 11565-11567 (2014). N. Ogihara, Y. Ozawa and O. Hiruta, J. Mater. Chem. A , 4 , 3398-3405 (2016). Y. Ozawa, N. Ogihara, M. Hasegawa, O. Hiruta, N. Ohba and Y. Kishida, Communs. Chem. , 1 , 65 (2018). N. Ogihara, N. Ohba and Y. Kishida, Sci. Adv. , 3 , e1603103 (2017). R. Mikita, N. Ogihara, N. Takahashi, S. Kosaka and N. Isomura, Chem. Mater. , 32 , 3396-3404 (2020). H. Hazama, D. Murai, N. Nagasako, M. Hasegawa and N. Ogihara, Adv. Mater. Technol. , 5 , 2000254 (2020). N. Ogihara, M. Hasegawa, H. Kumagai and H. Nozaki, ACS Nano , 15 , 2719-2729 (2021). N. Ogihara, M. Hasegawa, H. Kumagai, R. Mikita and N. Nagasako, Nat. Commun. , 14 , 1472 (2023). Figure 1 Metal-organic framework ; Electrode ; Materials science ; Metal ; Nanotechnology ; Environmental science ; Chemistry ; Metallurgy ; Organic chemistry ; Adsorption ; Physical chemistry Metal-Organic Frameworks: Synthesis and Applications