Recently; one-dimensional (1D) nanostructure field-effect transistors (FETs) have attracted much attention because of their potential application in gas sensing. Micro/nanoscaled field-effect sensors combine the advantages of 1D nanostructures and the characteristic of field modulation. 1D nanostructures provide a large surface area-volume ratio; which is an outstanding advantage for gas sensors with high sensitivity and fast response. In addition; the nature of the single crystals is favorable for the studies of the response mechanism. On the other hand; one main merit of the field-effect sensors is to provide an extra gate electrode to realize the current modulation; so that the sensitivity can be dramatically enhanced by changing the conductivity when operating the sensors in the subthreshold regime. This article reviews the recent developments in the field of 1D nanostructure FET for gas detection. The sensor configuration; the performance as well as their sensing mechanism are evaluated.
Intrinsically stretchable gas sensors possess outstanding advantages in seamless conformability and high‐comfort wearability for real‐time detection toward skin/respiration gases, making them promising candidates for health monitoring and non‐invasive disease diagnosis and therapy. However, the strain‐induced deformation of the sensitive semiconductor layers possibly causes the sensing signal drift, resulting in failure in achievement of the reliable gas detection. Herein, a surprising result that the stretchable organic polymers present a universal strain‐insensitive gas sensing property is shown. All the stretchable polymers with different degrees of crystallinity, including indacenodithiophene‐benzothiadiazole (PIDTBT), diketo‐pyrrolo‐pyrrole bithiophene thienothiophene (DPPT‐TT) and poly[4‐(4,4‐dihexadecyl‐4H‐cyclopenta[1,2‐b:5,4‐b′]dithiophen‐2‐yl)‐alt‐[1,2,5]thiad‐iazolo [3,4‐c] pyridine] (PCDTPT), show almost unchanged gas response signals in the different stretching states. This outstanding advantage enables the intrinsically stretchable devices to imperceptibly adhere on human skin and well conform to the versatile deformations such as bending, twisting, and stretching, with the highly strain‐stable gas sensing property. The intrinsically stretchable PIDTBT sensor also demonstrates the excellent selectivity toward the skin‐emitted trimethylamine (TMA) gas, with a theoretical limit of detection as low as 0.3 ppb. The work provides new insights into the preparation of the reliable skin‐like gas sensors and highlights the potential applications in the real‐time detection of skin gas and respiration gas for non‐invasive medical treatment and disease diagnosis.
A multiple drop-casting method of growing the ultralong dibenzo-tetrathiafulvalene (DB-TTF) micro/nanowire arrays has been developed which has the success ratio as high as 94%. This method enables the arrays with a length over a few hundreds of micrometers to locate between droplets with the definite orientation. The width of the micro/nanowires is controlled via tuning the concentration of DB-TTF solution in dichloromethane. The large-scale arrays can be grown onto Si, SiO2, glass, and the flexible polyethylene terephthalate (PET) substrates. These results show the promising potential of this facile solution-based process for the growth of the high-quality organic micro/nanowires, the fabrication of high-performance and flexible devices, and the fabrication of controlled assemblies of nanoscale circuits for fundamental studies and future applications.
8 October 2020 in Journal of Materials Chemistry C
Proton conduction is explored through a crosslinking method in neutral-polysaccharide based organic synaptic transistors for biodegradable and ultraflexible neuromorphic applications.