A large number of inorganic materials form crystals with chiral symmetry groups. Enantioselectively synthesizing nanostructures of such materials should lead to interesting optical activity effects. Here we report the synthesis of colloidal tellurium and selenium nanostructures using thiolated chiral biomolecules. The synthesis conditions are tuned to obtain tellurium nanostructures with chiral shapes and large optical activity. These nanostructures exhibit visible optical and chiroptical responses that shift with size and are successfully simulated by an electromagnetic model. The model shows that they behave as chiral optical resonators. The chiral tellurium nanostructures are transformed into chiral gold and silver telluride nanostructures with very large chiroptical activity, demonstrating a simple colloidal chemistry path to chiral plasmonic and semiconductor metamaterials. These materials are natural candidates for studies related to interactions of chiral (bio)molecules with chiral inorganic surfaces, with relevance to asymmetric catalysis, chiral crystallization and the evolution of homochirality in biomolecules.
Bibliographical noteFunding Information:
This research was supported by The Israel Science Foundation grant no. 172/10, the James Frank programme on light–matter interaction. A.B.-M. is supported by the Adams Fellowship Program of the Israel Academy of Sciences and Humanities. Electron microscopy was performed at the Wolfson Applied Materials Research Centre at Tel Aviv University and at the Irving and Cherna Moskowitz Center for Nano and Bio-Nano Imaging at the Weizmann Institute of Science. Z.F. and A.O.G. were supported by Volkswagen Foundation (Germany). Use of the Center for Nanoscale Materials was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract Number DEAC02-06CH11357. The help of Dr Ronit Popovitz-Biro in obtaining the energy dispersive X-ray spectroscopy scan lines is gratefully acknowledged.