In Situ Self‐Assembled La and Y Nanoparticles Based on Biomineralization of Diatom Frustules to Boost the Electrochemical Performance of SiO ₂ Anodes for Lithium‐Ion Batteries

Abstract Using diatoms, a typical microbial system of biomineralization, as a template, La 2 O 3 and Y 2 O 3 are synthesized in situ via biological self‐assembly during the cultivation of diatoms in La 3+ /Y 3+ ‐containing media without any supplements, reducing agents or triggering agents. Then, diatom frustules modified with La and Y nanoparticles (NPs) are prepared via high‐temperature reduction and crystallization. Furthermore, it has been used as an anode material for lithium‐ion batteries and has excellent electrochemical properties. The DFT calculations reveal that the doping of La and Y changes the energy band structure near the Fermi level of SiO 2 and increases the current carrying density. The diatom frustule SiO 2 anodes loaded with La and Y nanoparticles (DBS@C‐La‐10 and DBS@C‐Y‐10) have specific discharge capacities of approximately 1021.3 and 980.7 mAh g −1 , respectively, after 220 cycles. This is the first study in which the mineralization behavior of rare earth elements on diatom frustules is reported and applied to anodes in lithium‐ion batteries. This work provides a new option for applying rare earth elements in the field of energy storage.