Researchers at Rensselaer Polytechnic Institute have discovered a new method for growing single-crystal nanorods and controlling their shape using biomolecules which could enable more efficient heat transfer methods. These new methods could be useful in the development of more powerful and efficient nano-scale heat pumps and devices that harvest electricity from heat.
The researchers were also able to create structures that branched off in different directions by carefully controlling the temperature, time, and amount of biomolecular surfactant used during synthesis of the nanorods. The two-material nanorods consist of a single-crystal bismuth telluride core encased in a shell of single-crystal bismuth sulfide. These "core-shell" nanorods have attractive physical properties and are expected to one day enable the development of new nanoscale thermoelectric devices for power generation, as well as nanoscale heat pumps for cooling hot spots in nanoelectronics devices.