Ionic self-assembly of porphyrin micro-nano structures for solar hydrogen evolution
type: CreativeWork
description: This research project develops self-assembled porphyrin micro-nano structures and their metal nanocomposites for efficient solar H2 evolution. The project is composed of three inter-related tasks. The first task is to develop the synthetic methods for preparing the binary porphyrin micro-nano structures by ionic self-assembly under various aqueous solution conditions. Although the porphyrin molecules have been widely studied in artificial photosynthesis, the porphyrin monomers absorb light in a limited range of the solar spectrum and are unstable in solution. In using ionic selfassembly of two oppositely charged porphyrin molecules, we successfully synthesized the more robust micro/nano clover-like structures to replace the porphyrin monomer, which also have red-shifted light absorption due to J-aggreate formation. In addition, the microscale porphyrin structures can be designed with photochemical and catalytic properties, which is useful in solar energy harvesting and conversion to desired hydrogen. Effect of reaction time, growth temperature, ionic strength, and metal interchange on the self-assembly process of these micro-nano structures is studied. I have also investigated the ability of these porphyrin micro-nano structures to photocatalytically reduce aqueous gold(I) and platinum(IV) complexes to initiate and form nanostructures decorated with metal nanostructures on their surfaces. Photocatalytic reduction of both gold(I) thiosulfate and thiourea complexes lead to the metal-clover porphyrin nanocomposites. The platinized micro-nano clovers catalyze H2 generation utilizing visible light and a sacrificial electron donor at pH 3. The photoconductive ZnTPPS4-/SnT(N-EtOH-4-Py)P4+ porphyrin micro-nano structures are able to deliver electrons directly to the platinum nanoparticles at the surface with sufficient reducing power to generate hydrogen directly. However, the efficiency of this process is greatly improved when a soluble electron (and proton) relay molecule…
abstract: This research project develops self-assembled porphyrin micro-nano structures and their metal nanocomposites for efficient solar H2 evolution. The project is composed of three inter-related tasks. The first task is to develop the synthetic methods for preparing the binary porphyrin micro-nano structures by ionic self-assembly under various aqueous solution conditions. Although the porphyrin molecules have been widely studied in artificial photosynthesis, the porphyrin monomers absorb light in a limited range of the solar spectrum and are unstable in solution. In using ionic selfassembly of two oppositely charged porphyrin molecules, we successfully synthesized the more robust micro/nano clover-like structures to replace the porphyrin monomer, which also have red-shifted light absorption due to J-aggreate formation. In addition, the microscale porphyrin structures can be designed with photochemical and catalytic properties, which is useful in solar energy harvesting and conversion to desired hydrogen. Effect of reaction time, growth temperature, ionic strength, and metal interchange on the self-assembly process of these micro-nano structures is studied. I have also investigated the ability of these porphyrin micro-nano structures to photocatalytically reduce aqueous gold(I) and platinum(IV) complexes to initiate and form nanostructures decorated with metal nanostructures on their surfaces. Photocatalytic reduction of both gold(I) thiosulfate and thiourea complexes lead to the metal-clover porphyrin nanocomposites. The platinized micro-nano clovers catalyze H2 generation utilizing visible light and a sacrificial electron donor at pH 3. The photoconductive ZnTPPS4-/SnT(N-EtOH-4-Py)P4+ porphyrin micro-nano structures are able to deliver electrons directly to the platinum nanoparticles at the surface with sufficient reducing power to generate hydrogen directly. However, the efficiency of this process is greatly improved when a soluble electron (and proton) relay molecule…
author: Tian, Yongming
language: English
keywords: Light Harvesting, Solar Hydrogen Evolution, Porphyrin, Ionic Self-Assembly, Water Splitting, Artificial Photosynthesis; Water--Electrolysis., Nanostructured materials., Nanocomposites (Materials), Porphyrins., Self-assembly (Chemistry)
date published: 2011-07-01T07:00:00Z
date modified: 2026-07-24T05:26:42Z
provider: University of New Mexico
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of New Mexico

PropertyValue
property ID: Handle
value: http://hdl.handle.net/1928/12819