Credit: Venkatraman lab
Researchers from Columbia University have published their research in which they constructed tunable single-molecule devices capable of attaching directly to a target molecule. The device opens the door for future applications of the technology that could include facilitating electron transport across the device.
Until now, researchers have been unable to demonstrate the functionality of using external light to control single-molecule devices. “With this work, we've unlocked a new dimension in molecular electronics, where light can be used to control how a molecule binds within the gap between two metal electrodes,” said Latha Venkataraman, professor of chemistry and applied physics at Columbia Engineering. “It's like flipping a switch at the nanoscale, opening up all kinds of possibilities for designing smarter and more efficient electronic components.”
Venkataraman has been studying the fundamentals of single-molecule devices for nearly two decades. In the study, published in Nature Communications, Venkataraman and her team landed on organo-metallic iron-containing ferrocene molecules that could be stacked together to create more complex structures. These ferrocene-based molecules could be oxidized using light, during which they would bind to the gold electrodes and could be used to connect the molecule to external circuitry.
“By harnessing the light-induced oxidation, we found a way to manipulate these tiny building blocks at room temperature, opening doors to a future where light can be used to control the behavior of electronic devices at the molecular level,” said Woojung Lee, a PhD student in Venkararaman’s lab.
The approach used could apply to other molecular terminations used for creating several other single-molecule devices. The researchers also demonstrated that these devices could be controlled by using light to alter the oxidation state of ferrocene, paving the way for future light-switchable sensors that would respond to a specific wavelength of light.