Rational Construction of Highly Tunable Donor–Acceptor Materials Based on a Crystalline Host–Guest Platform

Abstract

Organic donor-acceptor (D-A) systems based on charge-transfer complexes interactions have emerged as an attractive class of materials due to their potential applications in optoelectronic devices. [1] Thanks to the well-developed design and synthesis technology, the characteristics of organic molecules could be well tuned, allowing for the design of various charge-transfer systems. [1c,2] However, since the assembly of D and A species toward donor-acceptor system is complicated and usually affected by many factors, such as solvents or temperature, it is usually difficult to precisely predict and control the arrangement of these molecules in the long-range order for the attainment of the required performance of complexes. [3] Therefore, it is still a challenge for the controlled construction of organic charge-transfer complexes featuring well-illustrated principles of rational construction and modulated performance, and the regulation of D and A species arrangement could be a key factor.Considering the well-defined arrangement of species in molecular level, the crystalline host-guest system could be an ideal platform for the rational construction of donor-acceptor system. As a class of well-developed crystalline material, metalorganic frameworks (MOFs) offer a new age for materials due to their excellent chemical/physical properties and potential applications in energy storage, [4] separation, [5] biomedicine, [6] sensing, [7] catalysis, [8] and so on. In addition, it is straightforward to modulate the crystalline structures as well as the inorganic-organic hybrid composition of MOFs through the choice of abundant organic components. Therefore, the surface chemistry of the pores in MOFs could be readily modulated based on rational utilization of organic building blocks. In addition, ordered arrangements of guest species could be achieved in MOFs as a host by taking advantage of the welldefined porous frameworks. More importantly, as the assembly of MOFs is based on the coordination bonds between metal ions and organic linkers, their construction usually shows more predictable trend in comparison to the self-assembly process of pure organic molecules through relatively weak supramolecular interactions. All these advantages mentioned above make MOFs an ideal host platform for the fabrication and systematic investigation of host-guest systems for various applications.Organic donor-acceptor systems have attracted much attention due to their various potential applications. However, the rational construction and modulation of highly ordered donor-acceptor systems could be a challenge due to the complicated self-assembly process of donor and acceptor species. Considering the well-defined arrangement of species at the molecule level, a crystalline host-guest system could be an ideal platform for the rational construction of donor-acceptor systems. Herein, it is shown how the rational construction of highly tunable donor-acceptor materials can be achieved based on a crystalline host-guest platform. Within the well-e...

Organic Cocrystals: Beyond Electrical Conductivities and Field‐Effect Transistors (FETs)

“…5years later, Hu and co-workers [60] reported another multi-component WLE materials ( Figure 4, LA',L A 'T' 0.5 % ,L A 'T' 1% ,L A 'T' 3% ,L T ',L U ',L U 'T' 0.5 % , LU'T' 1% ,LU'T' 3% ,and LT'). [76][77][78] Ref. In these supramolecular systems,a ne fficient energy-transfer behavior from pyrene-OFN to pyrene-TCNB occurred due to the well-matched spectra of the precursors and as uitable energy D/A distance.I na ddition to above-mentioned two kinds of acceptors,t here are other acceptors that have been reported for tuning optical properties more recently.…”

“…In these supramolecular systems,a ne fficient energy-transfer behavior from pyrene-OFN to pyrene-TCNB occurred due to the well-matched spectra of the precursors and as uitable energy D/A distance.I na ddition to above-mentioned two kinds of acceptors,t here are other acceptors that have been reported for tuning optical properties more recently. [76][77][78] [74], [1], [26], [4], [21], [43], [ 60], [ 25], [65], [70], [68], [ 72] and [73].…”

Engineering Donor–Acceptor Heterostructure Metal–Organic Framework Crystals for Photonic Logic Computation

“…Forthe construction of D-A heterostructures using MOFs featuring host-guest capabilities,t he two main essential factors are confined space within the host matrix and strong D-A interactions.This will greatly influence the affinity of the guests and the stability of the resulting D-A systems.I nt he NKU-111 host matrix, the cage-based porous network and electron-deficient tpt ligands ( Figure 1a)a llow electron-rich guest molecules ( Figure 1b)t obe encapsulated into separated cages in the host MOF.T hese guest molecules are arranged in aface to face p-p stacking mode with tpt ligands, resulting in strong D-A interactions (Figure 1c). [33] In addition, guest-encapsulated NKU-111 exhibits enhanced stability and the guest molecules can be trapped in the lattice,allowing for the possibility of using as tepwise assembly method to synthesize spatially segregated heterostructures.T he obtained crystals are referred to as PAH@NKU-111 (PAH = anthracene for 1,phenanthrene for 2,pyrene for 3,triphenylene for 4,perylene for 5 and coronene for 6,respectively,as shown in Figure 1b.) TheB FDH crystal morphology calculation based on their crystal structure shows ah exagonal morphology with dominant growth direction along the [001] direction ( Figure 1d), which correlates well with that of the sample obtained ( Figure 1e).…”

“…[28][29][30][31][32] On the basis of these advantages,wehave developed an ew strategy for the rational construction of crystalline D-A materials utilizing ah ost-guest MOF as ap latform. [33] Herein, we further develop the strategy by aiming at the preparation and characterization of ar ich library of donor-acceptor heterostructure crystals (Scheme 1). Specifically,t he Do rAmoieties can be first introduced into the host framework as the ligand and the Aor Dg uests can be incorporated into the host matrix during or after crystallization.…”

“…Since this strategy allows for relatively independent modulation of the host and guest components with various Da nd Am oieties,t he engineering of the heterostructures with this strategy can be quite flexible.I no ur work, NKU-111, which is constructed with the electron-deficient 2,4,6-tri(pyridin-4-yl)-1,3,5-triazine (tpt) ligand as the Ac omponent, was selected as the MOF host based on our previous research of crystalline D-A materials. [33] Then, as eries of hierarchical crystals were obtained through epitaxial growth and stepwise introduction of different electron-rich polycyclica romatic hydrocarbons (PAHs) guests as Dc omponents.T hese hierarchical crystals exhibit anisotropic growth due to the anisotropic structure of the NKU-111 host. Therefore,t he morphology of the hierarchical crystals can be rationally modulated by controlling the reaction conditions.D omain dependent emission tuning is readily achieved within these hierarchical crystals based on spatially segregated guest-dependent D-A systems.…”