Light driven reactions
Photocatalytic classical polymers: tunable photocatalysts
Sunlight is a renewable abundant energy resource that can be used to promote chemical reactions. Increasingly, the utilization of this energy source has been targeted as a cleaner more environmentally friendly alternative to thermal energy. The emergence of photocatalytic materials has facilitated this shift. Mimicking natural processes such as photosynthesis these materials utilize solar energy to enable chemical reactions to proceed. Many molecular inorganic, transition metal-based complexes or organic dye compounds that absorb significantly in the visible spectrum have been intensely studied to harvest solar energy and catalyze organic photochemical reactions. Nevertheless, there are some intrinsic drawbacks associated with these homogeneous systems, such as high cost, toxicity of these rare metals, as well as limited availability and post-reaction purification steps for catalyst removal. The above-mentioned disadvantages have led material scientists to pursue the further development of tunable, reusable and transition metal-free photocatalysts for organic synthesis.
Recently the combination of organic dye, transition metal-based and small conjugated organic photocatalysts with classical polymer chemistry to create photocatalytic classical polymers has been reported. Classical polymers can be formed by a number of polymerization techniques including free radical, controlled radical and ring opening polymerization. These polymers are inexpensive and can be designed to have a wide range of physical properties. The combination of classical polymers with photoactive monomers creates a hybrid material that is easily recoverable and can enhance the stability of the photoactive species. Furthermore, the polymer matrix can be used to overcome inherent solubility issues of photocatalytic material. This approach also enables triggerable materials to be produced that can be controlled by an external trigger.
Our research group aims to develop photocatalytic polymers that can be used for specific applications. We are interested in using the tunability of this new material class to produce new easily recoverable heterogeneous photocatalysts for the production of high valuable compounds. Furthermore, we are interested in producing selective photocatalytic materials that can differentiate between reagents to selectively produce a desired product. Here, the physical properties of the polymeric material can be manipulated to promote certain reactions. Our research group is also interested in the use of classical polymer photocatalysts for therapeutic applications, where polymers can be designed for photodynamic therapy and also biorthogonal prodrug activation etc.
