Interface Reaction Energy, Average Cathode Potential and Electrochemical Stability

[sandeep_Kumar]

Dear Users and Developers,

Happy New Year to all of you. I see the Interface Reactions app on the Materials Project and feel it is a really excellent app for interface reactions on solid-state electrolytes and cathode materials. I have some questions regarding this. I would appreciate it if someone could answer the following questions:

1. Is the electrochemical stability voltage window of cathode materials identical to the average intercalation voltage for the cathode materials (Ceder et al., Phys. Rev. B: Condens. Matter Mater. Phys., 1997, 56, 1354)? Are they connected to each other?

2. How to choose an element reservoir? The addition of an elemental reservoir implies the construction of a so-called grand potential phase diagram.

Looking forward to hearing from you.

With kind regards,

Sandeep

[Surya_Timilsina]

Hi Sandeep, are you able to construct grand potential phase diagram?

[buithitham]

Hello, this is code for grand potential phase diagram

from mp_api.client import MPRester



with MPRester('API') as mpr:
    entries =mpr.get_entries_in_chemsys("Zn-Cu-O")
    
    


 entries

len(entries)

ZnCr2O4_entries = [e for e in entries if e.composition.reduced_formula =="Zn(CuO2)2"]

len(ZnCr2O4_entries)

print(ZnCr2O4_entries)

ZnCr2O4_groundstate = sorted(ZnCr2O4_entries, key = lambda e: e.energy_per_atom)[0]

ZnCr2O4_groundstate

from pymatgen.analysis.phase_diagram import PhaseDiagram

pd= PhaseDiagram(entries)

print(pd)

from pymatgen.analysis.phase_diagram import PDPlotter

plotter= PDPlotter(pd)

plotter.get_plot(pd)

pd.get_form_energy_per_atom(ZnCr2O4_groundstate)

pd = PhaseDiagram(entries)


from pymatgen.entries.computed_entries import GibbsComputedStructureEntry


entries_2000 = GibbsComputedStructureEntry.from_entries(entries, 1000)

pd_2000 = PhaseDiagram(entries_2000)
PDPlotter(pd_2000).get_plot()

pd_2000.get_form_energy_per_atom(ZnCr2O4_groundstate)

from pymatgen.analysis.phase_diagram import GrandPotentialPhaseDiagram

from pymatgen.core.composition import Element

oxygen = Element("O")

mu= 0

entries_1000 = GibbsComputedStructureEntry.from_entries(entries, 1000)

gpd = GrandPotentialPhaseDiagram(entries_1000, {oxygen : mu})

PDPlotter(gpd).get_plot()

[Surya_Timilsina]

Thank you @buithitham. I ran the code and got output. Did you consider an oxygen reservoir as open? Also, how to chose mu? In addition, do you have any idea how to calculate electrochemical stability window of solid electrolytes?