Molecule device

Since the notion of single molecule devices was put forward in the 1970s, the field of electronics has moved on in a very elegant (and profitable) fashion. Several areas have been developed, areas in which molecules might well provide advantages. We will complete this overview with a very brief description of some of these situations. 

As a class of n-type organic semiconductors, PBI derivatives have received considerable attention for a variety of applications [312, 313], for example, for organic or polymer light-emitting diodes (OLEDs and PLEDs) [314, 315], thin-film organic field-effect transistors (OFETs) [316, 317], solar cells [318, 319], and liquid crystals [320]. They are also interesting candidates for single-molecule device applications, such as sensors [321], molecular wires [322], or transistors [141]. 

Guo X, Nuckolls C (2009) Functional single-molecule devices based on SWNTs as point contacts. J Mater Chem 19 5470-5473... 

Keywords DNA binder Double-helical structure Intercalation Molecule device Nanostructure... 

The most efficient devices were obtained using a multilayer approach, i. e. using several transport layers, emitter, and blocking layer. Thus, ultimately device optimization can be done similarly to small-molecule devices by selecting the best materials for their function rather than by generating materials, which fulfill all functions at once, but with limited performance ( single-layer approach). 

Organic field effect transistor (OFET) devices have been fabricated from pBTTT polymer solutions and hole mobility values of up to 0.8cm /V s were reported in a nitrogen atmosphere. These values approach that of high performing evaporated small molecule devices and are comparable to amorphous silicon. In bottom gate, bottom-contact devices, in which the active semiconductor layer is the exposed top surface, the effect of different ambient conditions has been evaluated. Exposure to unpurified, ambient air in which the humidity is -50%, results in an initial increase in the off-current of the device. In filtered, low humidity air, transistor devices remain very stable over time. 

Experimental techniques, such as scanning tunnelling microscopes and atomic force microscopes, which can resolve individual molecules, have opened a new era towards single molecule devices. Despite sophisticated instruments capable of... 

In small-molecule devices (thin layers from 5 to 100 mn), each of these layers fulfills a specifie fimction, such as charge injection, charge transport, or light emission... 

So what will be the disruptive applications of single-molecule devices My prejudice is that they will be found in applications that interface electronics directly to chemistry and biochemistry. The primary economic driver of this must surely be the transformation of medicine into a quantitative, data-driven science. Computers have the power to digest and to analyze the enormous volumes of data required to characterize and analyze the detailed molecular composition of individual humans. 

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