YIS-MOF-2022

Transcript

1. Theoretical Insights on Porous Semiconducting Hydrogen-bonded Organic Frameworks based on a Tetrathiafulvalene Derivative María Esteve Rochina E-mail: maria.esteve-rochina@uv.es Twitter: @MEsteveRochina
2. Hydrogen-bonded Organic Frameworks (HOFs) are a class of porous materials formed by the assembly of organic molecules by means of hydrogen bonds, which can be enforced by other non-covalent interactions such as π-π stacking interactions. Hydrogen bond π-π stacking Ma et al., Cell Reports Physical Science, 2020, 1, 100024, Introduction 2
3. Introduction Characteristics Mild synthesis conditions Easy solution processability Self healing Self regeneration Metal-free Non-covalent interactions Applications Gas adsorption and separation Heterogeneous catalysis Luminescence and molecular sensing Biological applications Proton conduction Charge conduction 3
4. Applications: Charge conduction Introduction Strategies • Charge Transfer (CT) between donor and acceptor • Organic radicals with open-shell electronic structure • Oxidation/Reduction to generate charge carriers CT complex between TTF (donor) and TCNQ (acceptor) 4
5. Applications: Charge conduction TTF derivatives • TTF electron donor molecule • Easy to oxidize forming a radical species • SSinteractions 0.37 eV 0.74 eV C2v boat conformation D2h planar D2 twisted Introduction 5
6. HOFs studied Diethyl ether THF DMF  ”›•–ƒŽŽ‘‰”ƒ’Š‹… …•›‡–”› ›‰”‘—’ Triclinic ࡼഥ ૚ Experimentally obtained by María Vicent-Morales Dr. Guillermo Mínguez Espallargas 6 TTFTB
7. Computational Details Molecular Calculations Systems: TTFTB Level of theory: DFT HSE06/6-31G(d,p) Software: Gaussian-16 A03 Periodic Calculations Systems: MUV-20a, MUV-20b and MUV-21 Level of theory: DFT PBEsol Tier-1 (optimizations) DFT HSE06 Tier-1 (electronic structure) Software: FHI-AIMS Electronic couplings Systems: MUV-20a, MUV-20b and MUV-21 fragments and dimers Level of theory: FO-DFT PBE Tier-1 Software: FHI-AIMS 7
8. Molecular Calculations: TTFTB Gaussian HSE06/6-31G(d,p) 8 Gas phase Dielectric continuum HOMO LUMO Neutral Oxidized Spin Density
9. Molecular Calculations: TTFTB Gaussian HSE06/6-31G(d,p) 9 Gas phase Dielectric continuum HOMO LUMO SUMO D(-2.68 eV) SOMO D(-5.01 eV) SOMO E(-4.87 eV) SUMO E(-4.82 eV) Neutral Deprotonated Oxidized Spin Density
10. Molecular Calculations: TTFTB Gaussian HSE06/6-31G(d,p) 10 Gas phase Dielectric continuum HOMO LUMO SUMO D(-2.68 eV) SOMO D(-5.01 eV) SOMO E(-4.87 eV) SUMO E(-4.82 eV) Neutral Deprotonated Oxidized Spin Density
11. Molecular Calculations: TTFTB Gaussian HSE06/6-31G(d,p) 11 Gas phase Dielectric continuum HOMO LUMO SUMO D(-2.68 eV) SOMO D(-5.01 eV) SOMO E(-4.87 eV) SUMO E(-4.82 eV) Neutral Deprotonated Uncharged radical Oxidized Spin Density
12. Molecular Calculations: TTFTB Gaussian HSE06/6-31G(d,p) 12 Gas phase Dielectric continuum HOMO LUMO SUMO D(-2.68 eV) SOMO D(-5.01 eV) SOMO E(-4.87 eV) SUMO E(-4.82 eV) Neutral Deprotonated Uncharged radical Zwitterionic radical Oxidized Spin Density
13. Molecular Calculations: TTFTB Gaussian HSE06/6-31G(d,p) 13 Gas phase Dielectric continuum Deprotonation of TTFTB leads to either an uncharged or a zwitterionic radical species depending on environment conditions. MUV 20a/b are expected to be present in its zwitterionic form. HOMO LUMO SUMO D(-2.68 eV) SOMO D(-5.01 eV) SOMO E(-4.87 eV) SUMO E(-4.82 eV) Neutral Deprotonated Uncharged radical Zwitterionic radical Oxidized Spin Density
14. Electronic Structure MUV-20a Flat bands Hopping mechanism l b d H i h i Bandgap (eV) 2.15 (D) 1.68 (E) FHI-AIMS HSE06/tier-1 (light) 14
15. Electronic Structure MUV-20a Flat bands Hopping mechanism l b d H i h i HOCO (D D) LUCO (D) LUCO (E) HOCO (E) Bandgap (eV) 2.15 (D) 1.68 (E) FHI-AIMS HSE06/tier-1 (light) 15
16. Electronic Structure MUV-20a Flat bands Hopping mechanism l b d H i h i Bandgap (eV) 2.15 (D) 1.68 (E) FHI-AIMS HSE06/tier-1 (light) HOCO (D D) LUCO (D D) LUCO (E) HOCO (E) 16 16
17. Electronic Structure MUV-20a Flat bands Hopping mechanism l b d H i h i Bandgap (eV) 2.15 (D) 1.68 (E) FHI-AIMS HSE06/tier-1 (light) HOCO (D D) LUCO (D) LUCO (E) HOCO (E) 17
18. Electronic Structure MUV-20b Flat bands Hopping mechanism Bandgap (eV) 2.24 (D) 1.52 (E) HOCO (D D) HOCO (E) LUCO (D) LUCO (E) FHI-AIMS HSE06/tier-1 (light) 18
19. Electronic Structure MUV-21 Flat bands Hopping mechanism Bandgap (eV) 1.42 FHI-AIMS HSE06/tier-1 (light) 19
20. Electronic Structure MUV-21 Flat bands Hopping mechanism HOCO LUCO Bandgap (eV) 1.42 FHI-AIMS HSE06/tier-1 (light) 20
21. Electronic Structure MUV-21 Flat bands Hopping mechanism HOCO LUCO Bandgap (eV) 1.42 FHI-AIMS HSE06/tier-1 (light) 21
22. Polaron The size of the polaron was found to be localized over few TTF units, supporting a hopping-like transport mechanism Gaussian HSE06/6-31G(d,p) 22 MUV-21 MUV-20a MUV-20b MUV-21
23. Electronic Transfer and Charge Transfer Marcus equation ࢑ࢋ࢚ ൌ ʹߨ ¾ ࡶଶ Ͷߨߣ݇௕ ܶ ݁ି ఒ ସ௞್் 23 Hopping-like transport mechanism FHI-AIMS FO-DFT PBE Tier-1
24. Electronic Transfer and Charge Transfer MUV-20a MUV-20b MUV-21 Marcus equation ࢑ࢋ࢚ ൌ ʹߨ ¾ ࡶଶ Ͷߨߣ݇௕ ܶ ݁ି ఒ ସ௞್் 24 Hopping-like transport mechanism FHI-AIMS FO-DFT PBE Tier-1
25. Electronic Transfer and Charge Transfer Experimental Conductivity MUV-20a: 6.07 × 10-7 S cm1 MUV-20b: 1.35 × 10 -6 S cm-1 MUV-21: 6.23 × 10-9 S cm-1 MUV-20a MUV-20b MUV-21 ࢑ࢋ࢚ MUV-20a: 9.09 × 1012 (dimer A) / 7.98 × 1010 (dimer B) MUV-20b: 3.30 × 1012 (dimer A) / 5.51 × 1011 (dimer B) MUV-21: 1.21 × 1012 (dimer A) / 2.03 × 1010 (dimer B) Marcus equation ࢑ࢋ࢚ ൌ ʹߨ ¾ ࡶଶ Ͷߨߣ݇௕ ܶ ݁ି ఒ ସ௞್் 25 Hopping-like transport mechanism FHI-AIMS FO-DFT PBE Tier-1
26. Electronic Transfer and Charge Transfer • Conductivity depends on charge mobility and carrier concentration. • MUV-20a and MUV-20b, which present larger TTFTB electronic couplings and already contain the TTF•+/COO− polaron in the framework are expected to show a significant enhancement of charge transport compared to bare MUV-21. Experimental Conductivity MUV-20a: 6.07 × 10-7 S cm1 MUV-20b: 1.35 × 10 -6 S cm-1 MUV-21: 6.23 × 10-9 S cm-1 MUV-20a MUV-20b MUV-21 ࢑ࢋ࢚ MUV-20a: 9.09 × 1012 (dimer A) / 7.98 × 1010 (dimer B) MUV-20b: 3.30 × 1012 (dimer A) / 5.51 × 1011 (dimer B) MUV-21: 1.21 × 1012 (dimer A) / 2.03 × 1010 (dimer B) Marcus equation ࢑ࢋ࢚ ൌ ʹߨ ¾ ࡶଶ Ͷߨߣ݇௕ ܶ ݁ି ఒ ସ௞್் 26 Hopping-like transport mechanism FHI-AIMS FO-DFT PBE Tier-1
27. Conclusions • Charge transport mechanism in these HOFs can be explained in terms of a hopping mechanism along the TTF S stacking direction. • Generation of charge carriers on TTF promotes semiconductivity due to efficient hole transporting 1D TTF channels along the structure. • Engendering zwitterionic structures can be an alternative strategy to infuse conductivity in porous organic crystals. • Transport measurements place the zwitterionic MUV-20a and MUV-20b materials as the highest conducting HOFs so far. 27
28. Acknowledgments Thank you for your attention! Organizing committee of the YIS-2022 Funding: GVPROMETEO2020-077 Dr. Guillermo Mínguez Espallargas and María Vicent-Morales 28 Supervisors: Prof. Enrique Ortí and Dr. Joaquín Calbo. PID2020-119748GA-I00 funded by MCIN/ AEI/10.13039/501100011033