Stimuli-responsive devices are of great scientific interest for data-processing applications, such as redox-based Boolean logic gates. Now, Bruno Fabre, Institut des Sciences Chimiques de Rennes, and Han Zuilhof with co-workers in Wageningen University, have developed a novel all-solid AND logic gate which responds to non-chemical inputs irradiation (light) and applied electrical potential.
The functional surfaces were prepared by microcontact printing (mCP), in which a polydimethylsiloxane (PDMS) stamp was inked by an amino-substituted Ferrocene onto a preformed, reactive, acid fluoride-terminated alkenyl monolayer covalently bound to n-type H-Si(111) . Then, the unstamped regions were then backfilled with butylamine to produce nonelectroactive, butylamide-terminated chains around thepatterns. The communication with the Fe-charge-storage areas can be turned on with light, and the difference in capacitance compared to the butylamide-terminated regions is significantly large and one can assign different states.
Such tailor-made micrometer-sized patterns of redox-active monolayers can behave as light-activated molecular memory cells with unprecedented capacitance performances, and can be constructed so as to yield an efficient AND logical gate. Furthermore, this research will aid the development of other molecular logic functions. By using silicon surfaces micropatterned with two redox centers electrochemically oxidizable or reducible at two well-separated potentials, it should be possible to fabricate a series of all solid-state multi-input redox-based logic circuits in the near future.