Recently, Prof. Fuqiang Huang from the Key Laboratory of Intelligent Creation for Extreme Energy Materials of the Ministry of Education, School of Materials Science and Engineering, and Zhang jiang Institute for Advanced Study, Shanghai Jiao Tong University, has developed a lattice distortion engineering strategy enabled by Joule thermal shock technology. This approach successfully constructs a partially atomic-disordered phase and introduces oxygen vacancies within Ti2Nb10O29-x. Experimental results demonstrate that the induced non-equilibrium structure effectively broadens lithium-ion diffusion pathways, significantly accelerating ion transport kinetics. As a result, the engineered Ti2Nb10O29-x electrode exhibits outstanding electrochemical performance, maintaining excellent capacity retention under ultrahigh-rate conditions of 150 C and at an extremely low temperature of −40 °C. This work establishes a fundamental understanding of the relationship between atomic-scale disorder engineering and electrochemical kinetics, providing new insights into the rational design of advanced electrode materials that simultaneously achieve high energy density and high-power density for next-generation energy storage systems.
The research, entitled “Partial Atomic Disordered Ti2Nb10O29-x Induced by Joule Thermal Shock for Superior Lithium-Ion Storage,” has been published in Advanced Materials (DOI: 10.1002/adma.73607). Prof. Fuqiang Huang and Associate Researcher Wujie Dong are the corresponding authors and Dr. Yuwei Zhao is the first author.
The present study successfully develops an atomic-disordered and oxygen-vacancy-rich Ti2Nb10O29-x anode material through a Joule thermal shock strategy. This unique synthesis approach induces lattice distortion and partial atomic disordering at the atomic scale while simultaneously introducing abundant oxygen vacancies, resulting in the formation of a distinctive amorphous-shell/crystalline-core microstructure. Such a structural configuration provides a favorable physical foundation for subsequent rapid ion transport.
This strategy effectively addresses the long-standing challenges associated with conventional niobium-based oxide anodes, where the intrinsically long-range ordered Ti/Nb atomic arrangement restricts the full utilization of their high-rate capability and the relatively poor intrinsic electronic conductivity limits electrochemical kinetics. By breaking the conventional structural ordering and tailoring the local atomic environment, the engineered Ti2Nb10O29-x achieves accelerated charge transport and enhanced electrochemical performance.
Figure 1. Design, morphology, and crystal structure characterization of Ti2Nb10O29-x. a) Schematic diagram of thermal treatment process and corresponding crystal structure of S-Ti2Nb10O29, b) O-Ti2Nb10O29-x, and c) Ti2Nb10O29-x. d) SEM images with an inset of particle size distribution diagram, e) UV-visible absorption spectra with an inset of photograph and f) Rietveld refined XRD pattern of Ti2Nb10O29-x. g) HRTEM, h) inversed fast Fourier transform image, and i-j) STEM image of Ti2Nb10O29-x.
Figure 2. Atomic structure and arrangement of Ti2Nb10O29-x, and S-Ti2Nb10O29. a) PDF curves. b) Crystal structure. c) R-space EXAFS spectrum of Nb K-edge. d) Aberration-corrected HAADF-STEM images and corresponding zoomed-in views of ordered and f) disordered structure. e) The intensity profile of line scan along the Line 1 and g) Line 2. h) STEM images of Ti2Nb10O29-x corresponding i) EELS profiling of O K-edge and j) the oxygen signal intensity from the surface to bulk.
Figure 3. Material characterizations. a-c) XPS spectra of Ti 2p, b) Nb 3d, and c) O 1s. d) EPR spectra. e) Electrical conductivity at room temperature. f) N2 adsorption–desorption isotherms curves with an inset of BJH adsorption pore size distributions of Ti2Nb10O29-x, O-Ti2Nb10O29-x, and S-Ti2Nb10O29.
Figure 4. Electrochemical performance. a) Galvanostatic charge and discharge curves and b) rate performance of batteries with various electrode. c) The rate performance summary of other related anode materials recently. d) The long cycling performance of Ti2Nb10O29-x electrode at current of 10 C. e-f) The low temperature performance of Ti2Nb10O29-x electrode under -20 °C (e) and -40 °C (f) with current of 0.2 C. g) The contact angle with S-Ti2Nb10O29 and Ti2Nb10O29-x electrode at -20 °C.
Figure 5. Electrochemical kinetics analysis. a) CV curves at 0.2 mV s–1. b) CV curves with various scan rate from 0.2 to 1.0 mV s–1 of Ti2Nb10O29-x. c) Linear relationship between log (peak current) and log (scan rate) of peak 1 and peak 2. d) Pseudocapacitive contribution of Ti2Nb10O29-x at 1.0 mV s–1. e) Nyquist plots and f) Linear relationship between Z’ and ω-0.5. g) Li+ diffusion coefficient of Ti2Nb10O29-x and h) Ti2Nb10O29. i) In situ Nyquist plots of Ti2Nb10O29-x and j) S-Ti2Nb10O29.
Figure 6. Transport energy barrier and structural stability analysis. a) Density of state of S-Ti2Nb10O29 and b) Ti2Nb10O29-x. c) The energy barrier of Li+ diffused in S-Ti2Nb10O29, and Ti2Nb10O29-x. d) Nb K-edge XANES spectra. e) Nb K-edge XANES spectra of reference material and Ti2Nb10O29-x with discharge state at 1.0 V. f) Ex situ Nb 3d XPS spectra of Ti2Nb10O29-x at various potential. g) In situ XRD pattern and h) the lattice evolutions of Ti2Nb10O29-x during cycling. i) In situ Raman spectra of Ti2Nb10O29-x during cycling from 1.0 – 3.0 V.
In summary, this study presents an atomic-level topological etching-assisted Joule thermal shock strategy to construct a disordered Ti2Nb10O29-x anode material featuring abundant oxygen vacancies and a loosely packed crystal structure. This atomic disordering design not only establishes continuous Li+ transport pathways but also significantly improves both ionic and electronic migration kinetics, leading to enhanced pseudocapacitive contributions and substantially improved rate capability.
Advanced structural characterizations, including EXAFS, pair distribution function (PDF) analysis, and aberration-corrected STEM-HAADF imaging, confirm the highly disordered arrangement and spatial displacement of Ti/Nb atoms within the lattice. The disruption of long-range atomic ordering effectively enlarges Li-ion diffusion channels, increases accessible migration pathways, lowers ion migration barriers, and accelerates Li-ion diffusion kinetics.
Benefiting from these structural advantages, the engineered Ti2Nb10O29-x electrode delivers outstanding high-rate performance up to 150 C and maintains stable cycling capability even under an extremely low temperature of −40 °C. This work provides a novel strategy for regulating atomic ordering in electrode materials and offers important guidance for the design and optimization of high-rate anodes and high-power-density energy storage systems.