联系我们
意见反馈

关注公众号

获得最新科研资讯

Menghao Yang Research Group

Intro block Computational Material Science Group at Tongji University

Share
Introduction to the laboratory

The Computational Materials Science Group at Tongji University was established by Dr. Menghao Yang. We are committed to combining traditional computational materials science with emerging artificial intelligence, overcoming the limitation that the original theoretical model cannot truly describe the solid-solid interface mechanisms, taking the lead in establishing a large-scale atomic interface (100 nm x 100 nm) model (more than 10 million atoms), breaking through the simulation time and size limitations of previous atomic models, developing the new algorithms for stripping and plating solid-state batteries, and providing guidance for the design and development of new materials closely combined with experimental verification methods for in-depth research. We have close cooperation with Tsinghua University, Stanford University, University of Maryland, Technische Universität Darmstadt, Basque Center for Applied Mathematics, etc.

Research Interests:

1. Interfacial Atomistic Mechanism of Metal Stripping and Plating in Solid-State Batteries.

2. Design and Development of Inorganic Solid Electrolytes in Solid-State Batteries.

3. Electrochemical Calculation and Modeling of New Battery Materials.

4. Predicting Catalytic Performance of Layered Oxide Materials.

5. Interface Transport Mechanism of Cell Membrane Phospholipid Bilayer.

We are hiring!

Job advertisements: Multiple postdoctoral researchers in the field of artificial intelligence for energy materials.

Collaborative Electrocatalysis Research has been published in High-impact Journals of Nature Catalysis and Nature Communications

Link: https://www.nature.com/articles/s41929-024-01136-1

Link: https://www.nature.com/articles/s41467-024-45654-9

From Lithium to Next-Gen Materials

Link: https://www.materialssquare.com/workshop/2023

 

 

Solid-State Symphony: The Atomistic Rhythms of Lithium Deposition

Introduction:

Crystallization is an important phenomenon in materials science, physics, and chemistry  [1,2]. While crystallization induced by the change of temperature or solution is commonly studied, the crystallization under electrochemical deposition remains less explored, despite being a key process in the operation of metal electrodes, such as Li, Na, Mg, and Zn metal anodes for next-generation high-energy rechargeable batteries [3,4]. During electrochemical deposition, metal ions in the electrolyte are deposited and crystallized into metal particles. The energy barrier of the crystallization is a key contributor to the over-potential of electrochemical deposition, which should be minimized to improve the electrochemical performance of the metal anode. High overpotential or polarization leads to low power density, reduced materials utilization, low energy efficiency, and even battery failure, such as dendrite growth and short-circuiting during the plating of metal electrodes [5,6]. Further improvement of these metal anodes, such as Li metal anode, requires an understanding of crystallization processes during electrochemical metal deposition, especially at the atomistic level.

Uniqueness:

Here, using large-scale molecular dynamics simulations, we study and reveal the atomistic pathways and energy barriers of lithium crystallization at the solid interfaces. In contrast to the conventional understanding, lithium crystallization takes multi-step pathways mediated by interfacial lithium atoms with disordered and random-closed-packed configurations as intermediate steps, which give rise to the energy barrier of crystallization. This understanding of multi-step crystallization pathways extends the applicability of Ostwald’s step rule to interfacial atom states and enables a rational strategy for lower-barrier crystallization by promoting favorable interfacial atom states as intermediate steps through interfacial engineering. Our findings open rationally guided avenues of inter-facial engineering for facilitating the crystallization in metal electrodes for solid-state batteries and can be generally applicable for fast crystal growth.

Fig. 1 Atomistic modeling of lithium crystallization at solid-electrolyte interface during Li deposition. a The atomistic model comprises the Li metal slab (light blue) with the solid electrolyte (orange) in the MD simulations. b The ato- mistic structures of the Li–SE interface over a period of energy change during Li deposition. Over the duration of Li deposition, c the energy of Li metal slab referenced to crystalline bulk Li per area and d–f the number of Li atoms with different local configurations, such as body-centered cubic (BCC) and random hexagonal close-packed (rHCP), in the Li metal slab.

Methodology

Our atomistic model of Li–SE interface consists of a Li metal slab with (001) surface in contact with (001) surface of Li2O, which is a common interphase layer formed by the reduction of oxides SEs with Li metal (Fig. 1a). The details of the model and the interatomic potentials are described in Methods. To simulate the Li deposition, the Li atoms are randomly inserted crossing the diffusion channels of Li2O (Fig. 1a) at the rate of one Li every 2 ps corresponding to a current density of 0.16 nA/nm2. By directly modeling the dynamical process of Li insertion with full atomistic details and femtosecond time resolution (Fig. 1b), the large-scale MD simulations reveal the interface structures and the Li diffusion mechanisms at the Li–SE interfaces.

Applications & Future Outlook

To improve the electrochemical performance of Li metal anodes, it’s desirable to lower the energy barrier of Li crystallization, which is a key contributor to the overpotential for electrochemical deposition. The undesired overpotential caused by the kinetic barrier for Li plating at the Li–SE interface can potentially contribute to the nucleation, formation, and growth of lithium dendrite inside the pores or grain boundaries of SEs, and to the failure of the solid-state battery. Therefore, lowering the barrier of Li crystallization at Li–SE interfaces is important to mitigate dendrite formation in solid-state batteries. Based on the understanding of the multi-step pathways with interfacial atomistic states as intermediates, a rational strategy for facilitating crystallization and mitigating the kinetic barrier is to promote the favorable interfacial-atom intermediate, i.e. rHCP-Li, with lower energy and easier transition to the final BCC-Li state (Fig. 2). These interfacial atom states are determined by the Li–SE interface and can be tailored by interface engineering.

 

Fig. 2  A schematic of multiple-step pathways of Li crystallization. The Li+ (orange, anion shown in red) in solid electrolytes (SE) goes through disordered-Li (cyan) and/or rHCP (random hexagonal close-packed)-Li (green) in the interfacial Li layer at the SE interface, and transforms into the crystalline BCC (body-centered cubic)-Li metal (blue).

References

1. De Yoreo, J. J. et al. Crystallization by particle attachment in syn- thetic, biogenic, and geologic environments. Science 349, aaa6760 (2015).

2. Li, B., Zhou, D. & Han, Y. Assembly and phase transitions of colloidal crystals. Nat. Rev. Mater. 1, 15011 (2016).

3. Chen, Y. et al. Li metal deposition and stripping in a solid-state battery via Coble creep. Nature 578, 251–255 (2020).

4. Zheng, J. et al. Reversible epitaxial electrodeposition of metals in battery anodes. Science 366, 645–648 (2019).

5. Kasemchainan, J. et al. Critical stripping current leads to dendrite formation on plating in lithium anode solid electrolyte cells. Nat. Mater. 18, 1105–1111 (2019).

6. Ning, Z. et al. Visualizing plating-induced cracking in lithium-anode solid-electrolyte cells. Nat. Mater. 20, 1121–1129 (2021).

Link: https://www.materialssquare.com/blog/Lithium-Deposition

Interfacial Atomistic Mechanisms of Lithium Metal Stripping and Plating in Solid-State Batteries

All-solid-state batteries based on a Li metal anode represent a promising next-generation energy storage system, but are currently limited by low current density and short cycle life. Further research to improve the Li metal anode is impeded by the lack of understanding in its failure mechanisms at lithium–solid interfaces, in particular, the fundamental atomistic processes responsible for interface failure. Here, using large-scale molecular dynamics simulations, the first atomistic modeling study of lithium stripping and plating on a solid electrolyte is performed by explicitly considering key fundamental atomistic processes and interface atomistic structures. In the simulations, the interface failure initiated with the formation of nano-sized pores, and how interface structures, lithium diffusion, adhesion energy, and applied pressure affect interface failure during Li cycling are observed. By systematically varying the parameters of solid-state lithium cells in the simulations, the parameter space of applied pressures and interfacial adhesion energies that inhibit interface failure during cycling are mapped to guide selection of solid-state cells. This study establishes the atomistic modeling for Li stripping and plating, and predicts optimal solid interfaces and new strategies for the future research and development of solid-state Li-metal batteries.

Publication: M. H. Yang, Y. S. Liu, A. M. Nolan, Y. F. Mo, Interfacial Atomistic Mechanisms of Lithium Metal Stripping and Plating in Solid‐State Batteries. Adv. Mater., 33, 2008081 (2021).

 

Interfacial Defect of Lithium Metal in Solid-State Batteries

All-solid-state battery with Li metal anode is a promising rechargeable battery technology with high energy density and improved safety. Currently, the application of Li metal anode is plagued by the failure at the interfaces between lithium metal and solid electrolyte (SE). However, little is known about the defects at Li–SE interfaces and their effects on Li cycling, impeding further improvement of Li metal anodes. Herein, by performing large-scale atomistic modeling of Li metal interfaces with common SEs, we discover that lithium metal forms an interfacial defect layer of nanometer- thin disordered lithium at the Li–SE interfaces. This interfacial defect Li layer is highly detrimental, leading to interfacial failure such as pore formation and contact loss during Li stripping. By systematically studying and comparing incoher- ent, coherent, and semi-coherent Li–SE interfaces, we find that the interface with good lattice coherence has reduced Li defects at the interface and has suppressed interfacial failure during Li cycling. Our finding discovered the critical roles of atomistic lithium defects at interfaces for the interfacial failure of Li metal anode, and motivates future atomistic-level interfacial engineering for Li metal anode in solid-state batteries.

Publication: M. H. Yang, Y. F. Mo, Interfacial defect of lithium metal in solid-state batteries. Angew. Chem. Int. Ed., 60, 2-10 (2021).

Lithium Crystallization at Solid Interfaces

Understanding the electrochemical deposition of metal anodes is critical for high-energy rechargeable batteries, among which solid-state lithium metal batteries have attracted extensive interests. A long-standing open question is how electrochemically deposited lithium-ions at the interfaces with the solid-electrolytes crystalize into lithium metal. Here, using large-scale molecular dynamics simulations, we study and reveal the atomistic pathways and energy barriers of lithium crystallization at the solid interfaces. In contrast to the conventional understanding, lithium crystallization takes multi-step pathways mediated by interfacial lithium atoms with disordered and random-closed-packed configurations as intermediate steps, which give rise to the energy barrier of crystallization. This understanding of multi-step crystallization pathways extends the applicability of Ostwald’s step rule to interfacial atom states, and enables a rational strategy for lower-barrier crystallization by promoting favorable interfacial atom states as intermediate steps through interfacial engineering. Our findings open rationally guided avenues of interfacial engineering for facilitating the crystallization in metal electrodes for solid-state batteries and can be generally applicable for fast crystal growth.

Publication: M. H. Yang, Y. S. Liu, Y. F. Mo, Lithium Crystallization at Solid Interfaces. Nat. Commun., 14, 2986 (2023).

visits:3384