Porous semiconductor film morphologies facilitate fluid diffusion and mass transport into the charge-carrying layers of diverse electronic devices. Here, we report the nature-inspired fabrication of several porous organic semiconductor-insulator blend films [semiconductor: P3HT (p-type polymer), C8BTBT (p-type small-molecule), and N2200 (n-type polymer); insulator: PS] by a breath figure patterning method and their broad and general applicability in organic thin-film transistors (OTFTs), gas sensors, organic electrochemical transistors (OECTs), and chemically doped conducting films. Detailed morphological analysis of these films demonstrates formation of textured layers with uniform nanopores reaching the bottom substrate with an unchanged solid-state packing structure. Device data gathered with both porous and dense control semiconductor films demonstrate that the former films are efficient TFT semiconductors but with added advantage of enhanced sensitivity to gases (e.g., 48.2%/ppm for NO₂ using P3HT/PS), faster switching speeds (4.7 s for P3HT/PS OECTs), and more efficient molecular doping (conductivity, 0.13 S/m for N2200/PS).

The development of p-type metal oxide thin-film transistors (TFTs) is far behind the n-type counterparts. Here, p-type CuAlO2 thin films were deposited by spin coating and annealed in nitrogen atmosphere at different temperature. The effect of post-annealing temperature on the microstructure, chemical compositions, morphology, and optical properties of the thin films was investigated systematically. The phase conversion from a mixture of CuAl2O4 and CuO to nanocrystalline CuAlO2 was achieved when annealing temperature was higher than 900 °C, as well as the transmittance, optical energy band gap, grain size, and surface roughness of the films increase with the increase of annealing temperature. Next, bottom-gate p-type TFTs with CuAlO2 channel layer were fabricated on SiO2/Si substrate. It was found that the TFT performance was strongly dependent on the physical properties and the chemical composition of channel layer. The optimized nanocrystalline CuAlO2 TFT exhibits a threshold voltage of − 1.3 V, a mobility of ~ 0.1 cm2 V−1 s−1, and a current on/off ratio of ~ 103. This report on solution-processed p-type CuAlO2 TFTs represents a significant progress towards low-cost complementary metal oxide semiconductor logic circuits.

Here, we report a new strategy to fabricate high performance thin-film transistors (TFTs) by doping gallium (Ga) both in channel (In2O3) and dielectric (Al2O3) layers. The influence of Ga doping on the microstructure and surface morphology of In2O3 films, as well as the oxygen defects states and electrical properties of Al2O3 films have been systematically investigated. The results show Ga doping frustrates In2O3 crystallization and flattens film surface. As for Al2O3, Ga doping increase the dielectric constant, reflective index and decrease the leakage current density. Furthermore, metal oxide TFTs were developed when using In2O3:Ga as the channel and Al2O3:Ga as the dielectric layers. The devices show improved electrical performance and enhanced positive and negative bias stress stability than undoped devices.

It has been reported that the output performance of a triboelectric nanogenerator (TENG) can be enhanced by applying light; however, the coupling mechanism between photogenerated carriers and triboelectric charges is still not well explained. Here, we propose a light-enhanced TENG based on a P3HT:PC₆₁BM active blend layer, which processes dual functions of the photoelectric effect and the triboelectric effect. The open-circuit voltage, short circuit current, and amount of transferred charges for the TENG were enhanced by 63%, 76%, and 127%, respectively, after illumination under the white light condition. Moreover, we have investigated the interaction between the triboelectric charges and the photogenerated carriers to further explore the coupling mechanism between the triboelectric and photoelectric effects. Both Kelvin probe force microscopy and conductive atomic force microscopy demonstrate that the photogenerated carriers produced by the P3HT:PC₆₁BM active blend layer can improve the surface triboelectric charge density. More interestingly, the transient absorption spectrum indicates that the electrostatic field induced by triboelectric charges contributes to the dissociation of excitons. In other words, there exists a beneficial promoting effect between the triboelectric charges and the photogenerated carriers during the operation of the light-enhanced TENG. This work provides an important guideline for the design and performance improvement of the hybrid TENG that captures both mechanical energy and light energy simultaneously.