| Autor: |
Mphahlele MG; Materials Modelling Centre, University of Limpopo, Private Bag X1106, Sovenga 0727, South Africa., Masedi MC; Materials Modelling Centre, University of Limpopo, Private Bag X1106, Sovenga 0727, South Africa., Malatji KT; Materials Modelling Centre, University of Limpopo, Private Bag X1106, Sovenga 0727, South Africa., Ngoepe PE; Materials Modelling Centre, University of Limpopo, Private Bag X1106, Sovenga 0727, South Africa., Ledwaba RS; Materials Modelling Centre, University of Limpopo, Private Bag X1106, Sovenga 0727, South Africa. |
| Abstrakt: |
Li 2 MnO 3 has garnered significant interest as a potential cathode material due to its high electrochemical capacity, cost-effectiveness, and eco-friendliness. Nonetheless, its practical utilization is hindered by structural deterioration, which results in rapid capacity and voltage decay during cycling. To mitigate these challenges, cationic dopants have been incorporated to minimize structural collapse and enhance cathode material performance. Consequently, there is a strong desire to identify novel doped configurations as a remedial strategy for optimizing Li 2 MnO 3 properties. In this study, the stability of the Li 2 Mn 1- x TM x O 3 system (TM = Ni, Co, Cr, Ru) was explored using cluster expansion and Monte Carlo simulations. By employing cluster expansion, binary ground state diagrams were generated, revealing 73, 65, 90, and 83 newly stable phases in Li 2 Mn 1- x Ni x O 3, Li 2 Mn 1- x Co x O 3 , Li 2 Mn 1- x Cr x O 3 , and Li 2 Mn 1- x Ru x O 3 , respectively. The outcomes indicated that Li 2 Mn 0.83 Ni 0.17 O 3 , Li 2 Mn 0.5 Co 0.5 O 3, Li 2 Mn 0.5 Cr 0.5 O 3 , and Li 2 Mn 0.5 Ru 0.5 O 3 represent the most stable doped phases within the Li 2 MnO 3 system. The application of Monte Carlo simulations enabled the assessment of high-temperature characteristics across the entire range of TM concentrations (0 ≤ x ≤ 1), facilitating the construction of phase diagrams. The Li 2 Mn 1- x Ni x O 3, Li 2 Mn 1- x Co x O 3 , Li 2 Mn 1- x Cr x O 3 , and Li 2 Mn 1- x Ru x O 3 systems exhibited favorable mixing at temperatures of 850, 700, 1700, and 1300 K, respectively. These discoveries present a clear trajectory for optimizing the properties of Li 2 MnO 3 , offering valuable insights into conceptualizing innovative cathode materials characterized by enhanced stability and performance.
Competing Interests: The authors declare no competing financial interest.
(© 2024 The Authors. Published by American Chemical Society.) |
