Yan Group @ NUS
Yan Group @ NUS
Without any doubt, the future organic carbon-based chemicals will be produced from sustainable feedstocks. However, current knowledge and technologies available for treating the fossil fuels are not sufficient, if applicable, for processing many of these renewable resources. Our group aims at developing novel routes for the conversion of cellulose, lignin, chitin, and carbon dioxide, into useful intermediate chemicals and ultimately end products, through advanced catalysis. For polymeric starting materials (cellulose, lignin, chitin), the major approach is to use tailor made catalyst that could selectively break the linkages between repeating units so that the functional groups present in these natural polymers are partially retained. As such, products bearing a variety of functionalities (and therefore a variety of properties) could be obtained through selective degradation of these biomaterials. The type of chemicals being produced is largely determined by the original structure of their starting material, i.e., aromatic compound will be produced from lignin and alcohols and furan derivatives will be produced from cellulose. This means minimum chemical transformations are required to produce a certain chemical and therefore these chemical transformations are atom efficient and are likely to be economically more competitive and environmentally more friendly than current ones as well. For CO2 conversion, the key is to identify a few catalysts that could effectively activate CO2. Currently, Au, Pd and Pt based catalysts at nano and sub-nano dimensions are under development in our group.
Green chemistry and green chemical engineering require major scientific breakthroughs, in particular breakthroughs in catalysis, to make the new reactions/processes not only environmentally benign but also economically viable. Nanocatalysts, regarded as a bridge to the gap between traditional homogeneous and heterogeneous catalysts, preserve the desirable attributes of both systems and may hold the key to enable a ‘green’ future. Our group is devoted to exploring highly stable, active, selective and recyclable nanocatalyst to improve known chemical transformations that are vital to chemical industry. Furthermore, we are also interested to identify nanocatalyst for novel chemical reactions that can not be readily promoted by conventional catalysts. The major approaches include: 1) manipulating the nanoparticle core by changing their size, morphology and composition to alter their catalytic properties; 2) manipulating the nanoparticle stabilizer, which is achieved by designing tailored made capping agents that indirectly modify the catalytic property of the nanoparticles and 3) employing tailor made solvents to establish multifunctional systems that are able to perform tandem catalysis.