Hierarchical Assembly of l-Phenylalanine-Terminated Bolaamphiphile with Porphyrin Show Tunable Nanostructures and Photocatalytic Properties

Abstract

Demands related to clean energy and environmental protection promote the development of novel supramolecular assemblies for photocatalysis. Because of the distinctive aggregation behaviors, bolaamphiphiles with two hydrophilic end groups could be theoretically the right candidates for the fabrication of high-performance photocatalysis. However, photocatalytic applications based on bolaamphiphilic assemblies were still rarely investigated. Especially, the relationship between diverse assembled nanostructures and the properties for different applications is urgently needed to be studied. Herein, we demonstrate that using the hierarchical assembly of bolaamphiphiles could correctly induce the porphyrin supramolecular architectures with much better photocatalytic performances than the aggregations containing 450 times of the porphyrin molecules, even though both molecular structures as well as the J-aggregations of porphyrin building blocks are same in two different systems. Thus, the co-assembly of l -phenylalanine terminated bolaamphiphile (Bola-F) and the porphyrin containing four hydroxyl groups (tetrakis-5,10,15,20-(4-hydroxyphenyl)porphyrin) can form microtube in methanol and forms fibers/spheres in methanol/water mixture. For catalyzing the photodegradation of rhodamine B, the small amount of J-aggregated porphyrin within Bola-F microtubes show much better photocatalytic performance comparing with that of huge porphyrin J-aggregations in fibers/spheres. The supramolecular assemblies as well as the photocatalysis were thoroughly characterized by different spectroscopies and electron microscopy. It is demonstrated that the co-assembly with bolaamphiphiles could inhibit the energy transfer of porphyrin aggregation and subsequently benefit the electron transfer and corresponding photocatalysis under photo-irradiation. This work is not only useful for further understanding the hierarchically supramolecular assembly but also provides a new strategy for making novel functional supramolecular architectures based on the assembly of bolaamphiphiles and porphyrins.

Bimodal Heterogeneous Functionality in Redox‐Active Conjugated Microporous Polymer toward Electrocatalytic Oxygen Reduction and Photocatalytic Hydrogen Evolution

“…However, different nanostructuring of TAPA‐OPE‐mix and TAPA‐OPE‐gly polymers can be attributed to the asymmetric and symmetric side‐chain substitutions on OPE bola‐amphiphilic struts, respectively . Here, tuning in the morphology of materials is noteworthy and indeed a crucial factor for catalytic performances by the fact that nanotape structures provide more exposed catalytic surface compared with irregular spherical morphologies . More importantly, tuning of the morphology in CMP materials by subtle variation in substitutions is yet to be realized.…”

“…[29,58] Here, tuning in the morphology of materials is noteworthy and indeed ac rucial factor for catalytic performances by the fact that nanotapes tructures provide more exposed catalytic surfacec ompared with irregular spherical morphologies. [56,57] More importantly,t uning of the morphologyi nC MP materials by subtle variation in substitutions is yet to be realized. UV/Visa bsorption spectra of TAPA-OPE-mix and TAPA-OPE-gly in the solid state revealed that both CMPs exhibit broad absorbance in the range 250-600nm( Figure S8, Supporting Information).…”

“…Therefore, exploration of bimodal functionality for catalysis of both electro‐ and photochemical reactions would broaden the applications of CMPs in view of designing metal‐free robust materials to address the energy challenges. Another crucial parameter, which plays a pivotal role in catalytic performance and needs to be taken into account, is the morphology of the materials . This can be tuned and regulated by introducing long alky or glycol chains on the organic struts of the CMP materials .…”

“…Another crucial parameter,w hich plays ap ivotalr ole in catalytic performance and needs to be taken into account,i st he morphology of the materials. [56,57] This can be tuned and regulated by introducing long alky or glycolc hains on the organic struts of the CMP materials. [58] However, there is no straightforward methodology for controlling nanostructuring in CMP materials.I nt his context,d esigning redox-activeC MPs by integration of appropriate electron-donor and -acceptor organic moieties will lead to facile chargem igration andp robable electrocatalytic activity.…”

Amphiphilic Porphyrin Aggregates: A DFT Investigation

“…Porphyrin assemblies are widespread in nature, where they are engaged in essential processes, such as efficient transport or storage of oxygen through the blood plasma or electron transfer in photosynthesis. Inspired by the diverse self-assembly motifs in nature, researchers have constructed and applied synthetic porphyrin systems in a variety of applicative fields, ranging from photocatalysis to sensors and material science [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. Indeed, the choice of porphyrin-based building blocks to organize supramolecular systems is extremely advantageous for several reasons: (i) their chemical versatility supported by well-established synthetic methodologies; (ii) their distinctive optical features; and (iii) their invaluable photophysical and photochemical properties that enhance the assembled materials, with obvious impacts on the performance in technological applications.…”