Micropatterning techniques independent of high-cost facilities are highly appreciated in bioanalysis and optoelectronics. Here we report a novel nonlithographic method based on self-assembled honeycomb films with through pores for micropatterning of zinc oxide nanowires (ZnO NWs). The ordered films were prepared via the breath figure method and used as templates for the solution growth of ZnO NWs. The resultant ZnO NW micropatterns were characterized by scanning electron microscopy, energy dispersive X-ray spectrometry, X-ray diffraction, high-resolution transmission electron microscopy, and photoluminescence spectrometry. Room-temperature photoluminescence spectra indicate that the micropatterned ZnO NWs show greatly enhanced near-band-edge emission and have potential as high-efficiency blue or near-UV light emitters. This facile and versatile approach is further demonstrated by templating biomimetic hydroxyapatite and silver nanoparticles on polydopamine-coated substrates. This work provides an alternative route to fabricating micropatterned functional surfaces at low cost and high efficiency.

A combustion solution method was developed to fabricate amorphous ZnAlSnO (a-ZATO) for thin-film transistors (TFTs). The properties of a-ZATO films and behaviors of a-ZATO TFTs were studied in detail. An appropriate Al content in the matrix could suppress the formation of oxygen vacancies efficiently and achieve densely amorphous films. The a-ZATO TFTs exhibited acceptable performances, with an on/off current ratio of ∼106, field-effect mobility of 2.33 cm2·V−1·S−1, threshold voltage of 2.39 V, and subthreshold swing of 0.52 V/decade at an optimal Al content (0.5). The relation between on- and off-resistance of the ZATO TFT was also within the range expected for fast switching devices. More importantly, the introduced Al with an appropriate content had the ability to evidently enhance the device long-term stability under working bias stress and storage durations. The obtained indium- and gallium-free a-ZATO TFTs are very promising for the next-generation displays.

The doping of semiconductor nanocrystals (NCs) is crucial for the optimization of the performance of devices based on them. In contrast to recent progress on the doping of compound semiconductor NCs and silicon NCs, the doping of germanium (Ge) NCs has lagged behind. Here it is shown that Ge NCs can be doped with phosphorus (P) during synthesis by a nonthermal plasma. It is found that there are more P atoms in the NC near‐surface region than in the NC core. P doping modifies the surface state of Ge NCs. Compressive strain can be incuced in Ge NCs by P which can explain the P‐doping‐enhanced oxidation resistance of Ge NCs. Stable dispersions of P‐doped Ge NCs in acetonitrile can be cast to produce films for field‐effect transistors (FETs). FET analysis shows that the electrical conductivity and electron mobility of a Ge‐NC film increase with the increase of the P doping level, although the electrical activation efficiency of P in the Ge‐NC film is low. Finally, atomic layer deposition of aluminum oxide at the surface of P‐doped Ge NCs is shown to improve the performance of the FETs.

Amorphous zinc-indium-tin oxide (a-ZITO) thin-film transistors (TFTs) have been prepared using a low-temperature combustion process, with an emphasis on complete miscibility of In and Sn contents. The a-ZITO TFTs were comparatively studied in detail, especially for the working stability. The a-ZITO TFTs all exhibited acceptable and excellent behaviors from Sn-free TFTs to In-free TFTs. The obtained a-ZTO TFTs presented a field-effect mobility of 1.20 cm2 V−1 s−1, an on/off current ratio of 4.89 × 106, and a long-term stability under positive bias stress, which are comparable with those of the a-ZIO TFTs. The In-free a-ZTO TFTs are very potential for electrical applications with a low cost.

Zn doped Tin oxide (SnO 2 :Zn) nanoparticles have been synthesized by the chemical precipitation route with different thermal decomposition temperatures having emission intensities in visible light and narrowed bandgap. Band gap narrowing and emission intensities can be controlled by doping and calcination. The average particle sizes estimated by TEM agree with those calculated by XRD to be around 18.48 and 21.44 nm and the optical bandgap values found to be 1.30 and 2.52 eV in SnO 2 :Zn annealed at 400 and 600°C, respectively. Blue shift in bandgap and decrease in photoluminescence intensity is noticed in (SnO 2 :Zn) nanoparticles with high annealing temperature, which is due to large grain sizes. As the grain sizes grow so defect density decreases and crystallanity increases. These defects act as luminescent centers and cause decrease in emission intensity and increase in band gap.

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Amorphous zinc-tin oxide (a-ZTO) thin-film transistors (TFTs) were prepared using a combustion solution method. The properties of the a-ZTO films and a-ZTO TFTs were studied in detail. For applications, a-ZTO TFTs are used as solvent sensors. The a-ZTO TFTs exhibited strong sensitivity and selectivity in detecting solvents (e.g., cyclohexane, ethanol, and deionized water). The electron donors in the ZTO channels were determinated by the polarity of the solvent, which affects the location of the Femi level (E f ). Moreover, a feasible mechanism model related to the electron transfer channel (ETC) was proposed to explain the sensor behaviours. This model can be applied to most of the amorphous oxide TFT sensors. This work is expected to not only provide an insight into the fundamental understanding of the behaviours of amorphous oxide TFT biosensors, but also to offer a basic design guideline for device fabrication in this system.

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