Multi-Functional 2D Covalent Organic Frameworks with Diketopyrrolopyrrole as Electron Acceptor
Liang Luo1, Chunbin Li2, Yuancheng Wang3
1State Key Laboratory of Applied Organic Chemistry (SKLAOC), Key Laboratory of Special Function Materials and Structure Design, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China.
Small (Weinheim an Der Bergstrasse, Germany)
|May 15, 2024
Summary
New 2D covalent organic frameworks (COFs) offer advanced optoelectronic applications. These materials demonstrate efficient photothermal conversion and supercapacitor performance, paving the way for novel electronic devices.
Area of Science:
- Materials Science
- Organic Electronics
- Nanotechnology
Background:
- 2D covalent organic frameworks (COFs) with conjugated structures are promising for organic optoelectronics.
- A lack of suitable π-skeletons has limited the development of optoelectronic COFs.
Purpose of the Study:
- To construct novel multi-functional optoelectronic 2D COFs using diketopyrrolopyrrole (acceptor) and tetraphenylpyrene or triphenylbenzene (donors).
- To investigate the optoelectronic properties, including photothermal conversion, supercapacitor performance, and ambipolar semiconducting behavior.
Main Methods:
- Synthesis of two 2D COFs, DPP-TPP-COF and DPP-TBB-COF, via imine bond formation.
- Characterization of crystallinity, π-stacking, and electronic structures.
- Evaluation of photothermal conversion efficiency, supercapacitor performance, and doping-induced ambipolar behavior.
Main Results:
- Both COFs exhibited good crystallinity with specific framework structures (rhombic and hexagonal).
- The D-A structure and ordered packing led to broad UV-vis absorption, narrow bandgaps, and suitable energy levels.
- DPP-TPP-COF achieved 47% photothermal conversion efficiency; DPP-TBB-COF showed a specific capacitance of 384 F g⁻¹.
- Achieved ambipolar semiconducting behavior through P-type and N-type doping of a single COF host.
Conclusions:
- The developed 2D COFs possess multi-functional optoelectronic properties.
- These materials offer a new platform for advanced applications in organic optoelectronics and energy storage.
- The study provides a model for designing and utilizing multi-functional optoelectronic COF materials.
Related Concept Videos
01:13Five-Membered Heterocyclic Aromatic Compounds: Overview
3.9K
Heterocyclic aromatic compounds are cyclic compounds that are aromatic and have one or more heteroatoms—atoms other than carbon, in the ring. Depending upon the number of atoms present in the ring, they can be either five or six-membered. Examples of five-membered heterocyclic aromatic compounds include pyrrole, furan, thiophene, and imidazole. Pyrrole consists of one nitrogen atom having one lone pair of electrons. Furan and thiophene have one oxygen and one sulfur heteroatom,...
3.9K
01:26Thermal and Photochemical Electrocyclic Reactions: Overview
2.3K
Electrocyclic reactions are reversible reactions. They involve an intramolecular cyclization or ring-opening of a conjugated polyene. Shown below are two examples of electrocyclic reactions. In the first reaction, the formation of the cyclic product is favored. In contrast, in the second reaction, ring-opening is favored due to the high ring strain associated with cyclobutene formation.
2.3K
01:18Aromatic Hydrocarbon Anions: Structural Overview
2.8K
Neutral hydrocarbons like cyclopentadiene with an odd number of carbon atoms and one intervening CH2 group in the ring are not aromatic. Cyclopentadiene with 4 π electrons does not satisfy the 4n + 2 π electron rule. Additionally, the intervening CH2 group is sp3 hybridized and lacks a vacant p orbital, thereby interrupting the overlap of p orbitals in a continuous manner and preventing the delocalization of π electrons throughout the ring.
Due to the absence of continuous...
Due to the absence of continuous...
2.8K
01:18Aromatic Hydrocarbon Cations: Structural Overview
2.8K
Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
Removing one hydrogen from the intervening CH2 group...
Removing one hydrogen from the intervening CH2 group...
2.8K
01:26Photochemical Electrocyclic Reactions: Stereochemistry
1.8K
The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation
Selection Rules: Photochemical Activation
1.8K
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
42.4K
Tetrahedral Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
42.4K