Nanoparticle Approaches to Zeolitic Catalysts

Zeolites (porous aluminosilicates) are some of the most important industrial catalysts. There is worldwide recognition of the importance of manipulating zeolites to give improved functionality. The journal Science (2011, 334, 1629) rated this area of current research as one of the 10 most important. This proposal looks to completely change the way we think about the preparation of zeolite catalysts. This will be done through a completely new approach of taking a known zeolite of specific structure and chemistry, and selectively diassembling the solid into precisely defined nanoparticles which can then be reassembled into new materials. The key concept is that certain substituents in zeolites (particularly Ge) are naturally located in specific areas of the structure and are also hydrolytically unstable compared to Al/Si. This means that we can put Ge into only certain places in a zeolite, and then dissolve it out again to diassemble the zeolite into nanostructured particles. The key to the reassembly is that the nanoparticles have originated from a fully condensed zeolite, which means they are geometrically compatible with reassembly - this is not true for directly synthesised nanoparticles. This is a transformative approach to making zeolites because it offers an entirely new mechanism, will produce novel structures and will change the thinking in how zeolites can be made. The chemistry of the disassembly means that one cannot reassemble into the original structure - you will be guaranteed a different one. We also propose that these structures should be predictable - the goal of a designer zeolite for applications is one of the holy grails of the field.

Why is this transformative science and what impact will it have? The scientific activity described in this proposal represents a novel fundamental concept in porous materials science. As such there is significant potential for extremely high quality publications and significant impact. As described Science has listed the manipulation of zeolite catalysts as one of the ten most exciting areas of research, and this activity offers a completely new concept in this important area that offers the potential to prepare many hitherto unknown catalytic materials. I would expect the impact of such a novel method to be extremely significant in academia, but that interest will also be high in industry.

The use of zeolites in the chemicals industry is a well known and extensively used technology. In the very recent past there has, however, been a significant drive all around the world improve features like accessibility to increase the effectiveness of zeolite catalysts (highlighted by Science as described in the Case for Support). This type of research is likely to be of interest to larger companies. As well as the opportunity to prepare new solids, the proposed work also has the potential for improving the stability of interesting, but at present useless, solids via the process. Oil, energy and chemicals companies such as BP, Shell, Chevron, Sasol etc have all got significant commercial interests in the application of zeolites. A successful completion of this work will be of interest to such entities and dissemination of our results (under confidentiality agreements as necessary) will be completed to ensure maximum impact is achieved.