About

Xianming (David) Bai is an associate professor in the Department of Materials Science and Engineering at Virginia Tech. His research interests include computational materials science from the atomistic to mesoscale level, radiation effects in nuclear materials, defect and microstructural evolution in metals and oxides, thermal transport in ceramics, mechanical behavior of materials, phase transformations, and granular materials modeling. Bai holds a B.S. and M.S. from Fudan University in China, an M.S. from Johns Hopkins University, and a Ph.D. from Georgia Institute of Technology. He has received several honors and awards, including the Thomas G. Digges and Thomas G. Digges Jr. Faculty Fellow at Virginia Tech in 2020, the 2020 Virginia Tech College of Engineering Outstanding New Assistant Professor award, the NSF CAREER Award in 2019, and the ORAU Ralph E. Powe Junior Faculty Enhancement Award in 2018. Bai is affiliated with professional organizations such as the Materials Research Society, The Minerals, Metals & Materials Society, and the American Nuclear Society.

Research topics

• Chemistry
• Materials science
• Composite material
• Physics
• Optoelectronics
• Metallurgy
• Chemical physics
• Physical chemistry
• Nanotechnology

Selected publications

• Synthesis and multi-color emission properties of novel Na3KMg7(PO4)6: RE3+ (RE = Eu, Dy, Tb) phosphor for white LED and indoor plant growth

  Optical Materials · 2025-03-06 · 5 citations

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• Efficient compositional exploration for sluggish interstitial diffusion in FeNiCrCoCu high-entropy alloys using machine learning-kinetic Monte Carlo and Bayesian optimization

  Materialia · 2025-08-23 · 1 citations

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• Relevance of fcc-bcc interface structure to defect properties at interfaces in irradiation environment

  OSTI OAI (U.S. Department of Energy Office of Scientific and Technical Information) · 2024-02-07

  paratextOpen access

  Abstract Not Provided

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• A new analytical surface energy model for arbitrary (h k l) planes in BCC and FCC metals

  Surfaces and Interfaces · 2024-01-01 · 5 citations

  articleSenior authorCorresponding
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• Electrochemical Reduction of Perfluorooctanoic Acid (PFOA): An Experimental and Theoretical Approach

  Journal of the American Chemical Society · 2024-04-05 · 67 citations

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  Perfluorooctanoic acid (PFOA) is an artificial chemical of global concern due to its high environmental persistence and potential human health risk. Electrochemical methods are promising technologies for water treatment because they are efficient, cheap, and scalable. The electrochemical reduction of PFOA is one of the current methodologies. This process leads to defluorination of the carbon chain to hydrogenated products. Here, we describe a mechanistic study of the electrochemical reduction of PFOA in gold electrodes. By using linear sweep voltammetry (LSV), an E0′ of −1.80 V vs Ag/AgCl was estimated. Using a scan rate diagnosis, we determined an electron-transfer coefficient (αexp) of 0.37, corresponding to a concerted mechanism. The strong adsorption of PFOA into the gold surface is confirmed by the Langmuir-like isotherm in the absence (KA = 1.89 × 1012 cm3 mol–1) and presence of a negative potential (KA = 3.94 × 107 cm3 mol–1, at −1.40 V vs Ag/AgCl). Based on Marcus–Hush’s theory, calculations show a solvent reorganization energy (λ0) of 0.9 eV, suggesting a large electrostatic repulsion between the perfluorinated chain and water. The estimated free energy of the transition state of the electron transfer (ΔG‡ = 2.42 eV) suggests that it is thermodynamically the reaction-limiting step. 19F – 1H NMR, UV–vis, and mass spectrometry studies confirm the displacement of fluorine atoms by hydrogen. Density functional theory (DFT) calculations also support the concerted mechanism for the reductive defluorination of PFOA, in agreement with the experimental values.

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• Reactive flash sintering and characterization of bulk high entropy nitrides

  Journal of the European Ceramic Society · 2024-12-14 · 6 citations

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• First-principle studies of oxidation effects on grain boundary strength in nickel

  Materialia · 2023-03-13 · 13 citations

  articleOpen accessSenior authorCorresponding
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• Molecular dynamics studies of sluggish grain boundary diffusion in equiatomic FeNiCrCoCu high-entropy alloy

  Journal of Materials Science · 2023-05-22 · 21 citations

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• Experimental and Computational Studies of Stress Corrosion Cracking of Alloys 308/309 and 82/182 Weldments in Corrosive and Radiation Environment

  2023-12-27

  reportOpen access

  The goal of the project was to determine factors that influence SCC and IASCC in weldments found in LWR nuclear power plants. We focused on a SA508-304L SS weldment fabricated by EPRI using gas tungsten arc welding and used an aggressive BWR normal water chemistry (NWC) immersion environment. This weldment used 309L butter and 308L groove filler material. The microstructure of the 309L butter was non-uniform, exhibiting a 20–30μm thick martensitic layer closest to the SA508 interface, a 1–4 mm thick single γ austenite phase dilution zone, and a γ–δ duplex region extending to the 308L groove filler. The 308L groove filler had an entirely γ–δ duplex microstructure. Two approximately 1-inch thick 304L and SA508 plates approximately 12 by 6 square inches were joined using standard nuclear grade welding techniques. This included a post weld heat treatment of the 309L butter after application, a 0.32 cm fit-up root opening, and 57 bead lines of 308L groove filler applied in 18 layers. A 60 degree weld bevel angle was used and the 309L butter was 1.5 cm thick. Displacement cascade damage was induced using proton irradiation at the Michigan Ion Beam Laboratory. The incident proton energy was 2 MeV, the sample temperature was 360 ºC, and the calculated dpa value at 10 μm (60% of the Bragg peak depth of ~18 μm) was 5 dpa using the quick Kinchin-Pease model. Proton irradiation to this damage level required approximately 125 hours of beam time. Two types of samples were irradiated, tensile specimens and TEM bars. Samples were selected from all regions of the weldment, including the SA508-309L butter interface, the 309L-308L interface, and 308L-304L interface. The stainless steel alloys (304L, 308L, and 309L) within the heat affected zone are characterized by a duplex skeletal morphology of δ-ferrite and γ-austenite resulting from the recrystallization associated with weld fabrication. Approximately 7 to 8 mm of length along the specimen was irradiated. The gauge volume surfaces were mechanically polished and then electro-polished to remove mechanical damage from the mechanical polishing step prior to irradiation. Immersion tests were performed in a recirculating autoclave under BWR NWC conditions (2000 ppb wt. dissolved oxygen, neutral pH, 288 ºC, 10 MPa, and inlet water conductivity <100 nS/cm) to accelerate corrosion. Constant strain rate tests were performed either to failure or to approximately 5% strain. Strain rates of 10^-7 to 10^-6 mm/mm/s were used and typical immersion testing required four to six weeks to achieve failure or strains near 5%. Analysis primarily used advanced electron microscopy techniques of FIB lift out specimens.

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• High-throughput machine learning - Kinetic Monte Carlo framework for diffusion studies in Equiatomic and Non-equiatomic FeNiCrCoCu high-entropy alloys

  Materialia · 2023-11-20 · 11 citations

  articleSenior authorCorresponding
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Recent grants

• CAREER: Defect Energetics and Dynamics in Concentrated Alloys

  NSF · $551k · 2019–2025

Frequent coauthors

• Yongfeng Zhang

  21 shared

• Michael Tonks

  15 shared

• Blas P. Uberuaga

  11 shared

• Todd R. Allen

  University of Michigan–Ann Arbor

  11 shared

• Mo Li

  10 shared

• Daniel Schwen

  Idaho National Laboratory

  10 shared

• Anter El‐Azab

  Purdue University West Lafayette

  9 shared

• Yaxuan Zhang

  Shanghai Jiao Tong University

  9 shared

Awards & honors

• Thomas G. Digges and Thomas G. Digges Jr.. Faculty Fellow, V…
• 2020 VT College of Engineering Outstanding New Assistant Pro…
• ICTAS Junior Faculty Award, Virginia Tech, 2020
• National Science Foundation (NSF) CAREER Award, 2019
• ORAU Ralph E. Powe Junior Faculty Enhancement Award, 2018