Optimizing Photodetectors in Two-Dimensional Metal-Metalloporphyrinic Framework Thin Films

Abstract

Two-dimensional (2D) metalloporphyrin-based MOF thin films possessing abundant π−π interactions are promising materials for photoelectronic devices, but no reports on fabrication of photodetectors are available so far. Herein, a series of 2D MOF Zn 2 [TCPP(M)] (named ZnTCPP(M); TCPP = 5,10,15,porphyrin; M = Zn, Mn, Fe, and H 2 ) films with [001] orientation are fabricated on SiO 2 /Si substrates by the liquid-phase epitaxial (LPE) layer-by-layer (lbl) approach and further assembled to photodetectors. The obtained ZnTCPP(M)-based photodetectors exhibit an excellent photoresponse due to abundant π−π stacking between the MOF layers. Moreover, the metalloporphyrinic groups in ZnTCPP(M) have a significant influence on modulating the photoresponse of the photodetectors, among which the prepared ZnTCPP(Zn) film-based device exhibits the best photodetection performance with a high on/off ratio of 2.3 × 10 4 , responsivity (R λ , up to 10.3 A W −1 ), short rise/fall times (0.09/0.07 s), and a large detectivity (D*) of 8.1 × 10 13 Jones. Density functional theory (DFT) calculations reveal that the perturbation of the ring π-electron system and the introduction of low-lying states as well as the large delocalization of the metalloporphyrinic group will adjust the photodetection performance of ZnTCPP(M) films. These results will provide a new understanding of the modulation of 2D metalloporphyrinic MOFs toward photodetection performance and perspective for the fabrication of photoelectronic devices.

Oriented Surface‐Anchored Metal–Organic Frameworks (SurMOFs) as Electrochromic Thin Films

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and noninterpenetrated materials, [4] this method uses a very small amount of precursors (few mg cm −2 ) making SurMOFs ideal candidates for the integration of highly sophisticated ligands into functional materials.Owing to their high versatility and infinite combination of metallic centers and organic ligands, SurMOFs are of interest for a very wide range of applications, spanning from photoelectronics, catalysis, water remediation, or solar energy conversion. [5][6][7][8] Taking advantage of the highly oriented character of SurMOF, we extended the range of applications by investigating electrochromic properties. Electrochromism (EC) refers to a change of the optical properties of a material upon application of a voltage.

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Fabrication of Two-Dimensional Homo-Bimetallic Porphyrin Framework Thin Films for Optimizing Nonlinear Optical Limiting

“…The high-resolution XPS spectrum of Zn 2p for ZnTCPP(M) thin films showed two obvious peaks located at about 1021.1 and 1044.2 eV, which were assigned to the Zn(II) 2p 3/2 and Zn(II) 2p 1/2 states, respectively. 47,48 The peaks at binding energy of 397.8 and 399.8 eV in the N 1s from ZnTCPP(H 2 ) thin film could be attributed to the iminic nitrogen and pyrrolic nitrogen, respectively. 43,50−53 Nevertheless, the intensity of the pyrrolic and iminic nitrogen peaks decreased, and a single peak associated with metalloporphyrin complexes appeared at 398.6 eV in the N 1s spectra acquired for ZnTCPP(Zn) and ZnTCPP(Fe) thin films (Figure 1d), which was a characteristic peak of M−N coordination in the porphyrin units, in good accordance with the UV−vis spectrum results described above.…”

Chiral Metal–Organic Framework with Temperature-Dependent Homochirality for Chiral Discrimination

“…Figure shows the high-resolution Zn 2p, N 1s, C 1s, and O 1s XPS spectra of 25- d -Phe-OMe/Zn-TCPP. The Zn 2p spectra can be deconvoluted into two peaks at 1045.2 and 1022.2 eV (Figure A), corresponding to Zn 2p 1/2 and Zn 2p 3/2 , respectively . The N 1s spectra are divided into three peaks at 402.3 (−NH–C=O), 400.0 (−NH 2 ), and 397.9 eV (=N−) (Figure B), which originate from the amide bond, d -Phe-OMe, and TCPP unit, respectively.…”

“…The Zn 2p spectra can be deconvoluted into two peaks at 1045.2 and 1022.2 eV (Figure 6A), corresponding to Zn 2p 1/2 and Zn 2p 3/2 , respectively. 34 The N 1s spectra are divided into three peaks at 402.3 (−NH− C=O), 400.0 (−NH 2 ), and 397.9 eV (=N−) (Figure 6B), which originate from the amide bond, D-Phe-OMe, and TCPP unit, respectively. Note that the peak area of −NH 2 is significantly larger than that of −NH−C=O, implying that the interaction mode between TCPP and D-Phe-OMe is mainly noncovalent interactions (H-bond and π−π stacking) but not covalent interaction (amide bond) at 25 °C.…”