Electronic properties of selected metallophthalocyanines of iron using computational methods for ORR catalysis Palesa Phooko 2 and Getachew Adam 1 1 Addis Ababa Science and Technology University, Ethiopia, 2 National University of Lesotho, Lesotho The ORR at the cathode is particularly challenging as it involves a complex four (4) electron transfer mechanism. As a result, the ORR kinetics are very slow and highly irreversible. Thus, highly efficient ORR electrocatalysts are needed to drive the fuel cells. The density functional theory at the B3LYP level using LANL2DZ basis set was used for the investigation of electronic properties of the selected iron phthalocyanines as the potential electrocatalysts for oxygen reduction reaction (ORR). The electronic properties and chemical activity of the titled compounds were investigated by means of several theoretical approaches including geometry optimization, excited states and UV-Vis, molecular electrostatic potential surface, natural bond orbital, and frontier molecular orbital analyses. It was established that the use of electron donor substituents like the ethoxy group and DMSO for push up effect might boost the catalytic behavior of iron phthalocyanines. This was based on the stability, shorter Fe-N bond lengths, the HOMO-LUMO gaps and the band gap analysis. It was established that the use of nitro substituent and pyridine for push up effect might boost the catalytic behavior of iron phthalocyanines and this could be due to their electron withdrawing behavior. Since the positive regions are localized on the Fe 2+ site, which can be considered as possible sites for nucleophilic attack. Both NBO analysis and fukui function revealed that the Fe site is more electron deficient with the electron withdrawing substituents and electron donating axial ligands or bridging groups in a case of bimetallic systems. References 1. Bekaroglu O., Turkish Journal of Chemistry, 2014. 38 (6):21. Louise Breloy et al., . Polymer Chemistry, 2021. 12 :26. María Paz Oyarzún et al., Electrochimica Acta, 2021. 398 :13. Qianglong Qi et al., Advanced Energy & Sustainability Research, 2021. 2 :31. Susovan Bhowmik et al., Oxygen reduction reactionby metallocorroles and metallophthalocyanines , in Oxygen Reduction Reaction , S.C.a.K.D. Kushal Sengupta, Editor. 2022, Elsevier: 79-124. 2. J. Durst et al.,Energy & Environmental Science, 2014. 7 : 2255-2260. 3. H. Cruz-Martínez et al., Materials today Physics, 2021. 19 :100406-100411. Jasinski, R., Nature, 1964. 201 : 2 Bolong Yang et al.,Nano Energy, 2020. 101 : 107565-107575. 4. Anuj Kumar et al., Coordination Chemistry Reviews, 2020. 402 : 213047-213064. 5. Wenjuan Li et al., Journal of Materials Science & Technology 2023. 157 : 80-88. Anuj Kumar et al.,Chinese Journal of Catalysis, 2021. 42 :1404-1412. 6. Xuan Miao et al.,Chemical Engineering Journal, 2023. 465 : p. 142775-142784 Shaoxuan Yang et al., Chemical Society Reviews, 2021. 50 : p. 12875–13442 7. Norskov J., Progress in Surface Science, 1991. 38 :103-144 8. Wei Yan et al.,ACS Applied Materials & Interfaces, 2022. 14 : 50751-50761 Yao Ma et al., Advanced Functional Materials, 2020. 30 :2005000-2005007. Becke A., J. The Journal of Chemical Physics, 1993. 98 :5648-5652.
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