Controlled alignment and patterning of individual semiconducting nanowires at a desired position in a large area is a key requirement for electronic device applications. High-speed, large-area printing of highly aligned individual nanowires that allows control of the exact numbers of wires, and their orientations and dimensions is a significant challenge for practical electronics applications. Here we use a high-speed electrohydrodynamic organic nanowire printer to print large-area organic semiconducting nanowire arrays directly on device substrates in a precisely, individually controlled manner; this method also enables sophisticated large-area nanowire lithography for nano-electronics. We achieve a maximum field-effect mobility up to 9.7 cm 2 V À 1 s À 1 with extremely low contact resistance (o5.53 O cm), even in nano-channel transistors based on single-stranded semiconducting nanowires. We also demonstrate complementary inverter circuit arrays comprising well-aligned p-type and n-type organic semiconducting nanowires. Extremely fast nanolithography using printed semiconducting nanowire arrays provide a simple, reliable method of fabricating large-area and flexible nano-electronics.

and light-weight SCs with the capability of being rolled-up have fascinated particular interest in wearable and portable electronics as a next-generation power system. [4] To design these devices, textilebased electrodes with well-architectured nanomaterials are crucial. [5] Accordingly, several textile-based substrates which include carbon cloth, carbon nanotube coated fabric, carbon fiber paper, etc. have been explored for flexible SCs owing to their intertwined fibrous texture, high flexibility and excellent stability. [6] In fact, the carbon-based textiles/papers suffer from high hydrophobicity and low conductivity, and they are not suitable for clothing. Meanwhile, in view of the cost, the carbon textile/paper-based electrodes are expensive and the complicated process could be required to attain these substrates. [7] Therefore, it is important to pursue suitable alternatives with low cost and ecofriendliness for carbon-based textiles. [8,9] In this context, the conductive fabrics (CFs) which are fabricated with a simple wet-chemical-based plating of metallic layers on polyester fibers enable the prominence in several textile industries. [10] Such chemical-based coating methods can be easily scaled up for low-cost and large-scale production. [11] As a result of the strongly adhered metallic layers on polyester fibers, they can easily lift up the CFs for desirable properties including high conductivity, great flexibility, high mechanical stability and water washability. The attractive properties of CFs offer great potential for flexible electrodes in SCs.On the other hand, the recent development of nanomaterials and nanotechnology has enabled the advanced electroactive materials for high-performance SCs. Typically, SCs may store energy through two mechanisms which include electric double-layer capacitive (EDLC) process and faradaic redox reaction. [12,13] Because of the higher discharge capacity and multiple oxidation states, faradaic electroactive materials show higher electrochemical performance than EDLC materials. So far, transition metal hydroxide/oxides including Co(OH) 2 , ZnCo 2 O 4 , CuO, NiO, CoMoO 4 , NiCo-layered double hydroxide (LDH), etc. with versatile morphologies were investigated mainly as redox-active materials. [11,[14][15][16] However, the rate performance and stability of these transition metal hydroxides/oxides are still inferior because of their poor electrical Highly flexible and conductive fabric (CF)-supported cauliflower-like nickel selenide nanostructures (Ni 3 Se 2 NSs) are facilely synthesized by a singlestep chronoamperometry voltage-assisted electrochemical deposition (ECD) method and used as a positive electrode in supercapacitors (SCs). The CF substrate composed of multi-layered metallic films on the surface of polyester fibers enables to provide high electrical conductivity as a working electrode in ECD process. Owing to good electrical conductivity, high porosity and intertwined fibrous framework of CF, cauliflower-like Ni 3 Se 2 NSs are densely integrated onto the ent...

Although graphene can be easily p-doped by various adsorbates, developing stable n-doped graphene that is very useful for practical device applications is a difficult challenge. We investigated the doping effect of solution-processed (4-(1,3-dimethyl-2,3-dihydro-1H-benzoimidazol-2-yl)phenyl)dimethylamine (N-DMBI) on chemical-vapor-deposited (CVD) graphene. Strong n-type doping is confirmed by Raman spectroscopy and the electrical transport characteristics of graphene field-effect transistors. The strong n-type doping effect shifts the Dirac point to around -140 V. Appropriate annealing at a low temperature of 80 ºC enables an enhanced electron mobility of 1150 cm(2) V(-1) s(-1). The work function and its uniformity on a large scale (1.2 mm × 1.2 mm) of the doped surface are evaluated using ultraviolet photoelectron spectroscopy and Kelvin probe mapping. Stable electrical properties are observed in a device aged in air for more than one month.

One-dimensional nanowires (NWs) have been extensively examined for numerous potential nano-electronic device applications such as transistors, sensors, memories, and photodetectors. The ferroelectric-gate field effect transistors (Fe-FETs) with semiconducting NWs in particular in combination with ferroelectric polymers as gate insulating layers have attracted great attention because of their potential in high density memory integration. However, most of the devices still suffer from low yield of devices mainly due to the ill-control of the location of NWs on a substrate. NWs randomly deposited on a substrate from solution-dispersed droplet made it extremely difficult to fabricate arrays of NW Fe-FETs. Moreover, rigid inorganic NWs were rarely applicable for flexible non-volatile memories. Here, we present the NW Fe-FETs with position-addressable polymer semiconducting NWs. Polymer NWs precisely controlled in both location and number between source and drain electrode were achieved by direct electrohydrodynamic NW printing. The polymer NW Fe-FETs with a ferroelectric poly(vinylidene fluoride-co-trifluoroethylene) exhibited non-volatile ON/OFF current margin at zero gate voltage of approximately 10(2) with time-dependent data retention and read/write endurance of more than 10(4) seconds and 10(2) cycles, respectively. Furthermore, our device showed characteristic bistable current hysteresis curves when being deformed with various bending radii and multiple bending cycles over 1000 times.

Sophisticated preparation of arbitrarily long conducting nanowire electrodes on a large area is a significant requirement for development of transparent nanoelectronics. We report a position-customizable and room-temperature-processable metallic nanowire (NW) electrode array using aligned NW templates and a demonstration of transparent all-NW-based electronic applications by simple direct-printing. Well-controlled electroless-plating chemistry on a polymer NW template provided a highly conducting Au NW array with a very low resistivity of 7.5 μΩ cm (only 3.4 times higher than that of bulk Au), high optical transmittance (>90%), and mechanical bending stability. This method enables fabrication of all-NW-based electronic devices on various nonplanar surfaces and flexible plastic substrates. Our approach facilitates realization of advanced future electronics.