The functionalized conductive polymer is a promising choice for flexible triboelectric nanogenerators (TENGs) for harvesting human motion energy still poses challenges. In this work, a transparent and stretchable wrinkled poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) electrode based TENG (WP-TENG) is fabricated. The optimum conductivity and transparency of PEDOT:PSS electrode can reach 0.14 kΩ □ −1 and 90%, respectively, with maximum strain of ≈100%. Operating in single-electrode mode at 2.5 Hz, the WP-TENG with an area of 6 × 3 cm 2 produces an open-circuit voltage of 180 V, short-circuit current of 22.6 µA, and average power density of 4.06 mW m −2 . It can be worn on the wrist to harvest hand tapping energy and charge the capacitor to 2 V in ≈3.5 min, and then drive an electronic watch. Furthermore, the WP-TENG as the human motion monitoring sensor could inspect the bending angle of the elbow and joint by analyzing the peak value of voltage and monitor the motion frequency by counting the peak number. The triboelectric mechanism also enables the WP-TENG to realize high-performance active tactile sensing. The assembled 3 pixel × 3 pixel tactile sensor array is fabricated for mapping the touch location or recording the shape of object contacted with the sensor array.

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High-quality and wafer-scale graphene on insulating gate dielectrics is a prerequisite for graphene electronic applications. For such applications, graphene is typically synthesized and then transferred to a desirable substrate for subsequent device processing. Direct production of graphene on substrates without transfer is highly desirable for simplified device processing. However, graphene synthesis directly on substrates suitable for device applications, though highly demanded, remains unattainable and challenging. Here, we report a simple, transfer-free method capable of synthesizing graphene directly on dielectric substrates at temperatures as low as 600 °C using polycyclic aromatic hydrocarbons as the carbon source. Significantly, N-doping and patterning of graphene can be readily and concurrently achieved by this growth method. Remarkably, the graphene films directly grown on glass attained a small sheet resistance of 550 Ω/sq and a high transmittance of 91.2%. Organic light-emitting diodes (OLEDs) fabricated on N-doped graphene on glass achieved a current density of 4.0 mA/cm(2) at 8 V compared to 2.6 mA/cm(2) for OLEDs similarly fabricated on indium tin oxide (ITO)-coated glass, demonstrating that the graphene thus prepared may have potential to serve as a transparent electrode to replace ITO.

Graphene/metal nanoparticle (NP) composites have attracted great interest for various applications as catalysts, electrodes, sensors, etc., due to their unique structures and extraordinary properties. A facile synthesis of graphene/metal NP composites with good control of size and morphology of metal NPs is critical to the practical applications. A simple method to synthesize graphene/metal NPs under a controllable manner via a self-catalysis reduction at room temperature has been developed in this paper. At first, metal NPs with desirable size and morphology were decorated on GO and then used as catalyst to accelerate the hydrolysis reaction of NaBH4 to reduce the graphene oxide. Compared to the existing methods, the method reported here features several advantages in which graphene/metal NPs are prepared without using toxic and explosive reductant, such as hydrazine or its derivatives, making it environmentally benign, and the reaction can be processed at room temperature with high efficiency and in a large range of pH values. The approach has been demonstrated to successfully synthesize graphene composites with various metal NPs in large quantity, which opens up a novel and simple way to prepare large-scale graphene/metal or graphene/metal oxide composites under mild conditions for practical applications. For example, graphene/AuNP composites synthesized by the method show excellent catalytic capability.

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Honeycomb-like graphene oxide aerogel for high-efficiency PM2.5 capture was developed via directional freezing with introduction of modified tourmaline nano-particles.

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Two-dimensional (2D) nonlayered nanomaterials have attracted extensive attention for electronic and optoelectronic applications recently because of their distinct properties. In this work, we first employed a facile one-step method to synthesize 2D nonlayered cadmium sulfide selenide (CdS x Se 1−x , x = 0.33) nanosheets with a highly crystalline structure and then we introduced a generic spin-coating approach to fabricate hybrid nanomaterials composed of PbS quantum dots (QDs) and 2D CdS x Se 1−x nanosheets and demonstrated their potential for high-performance broadband photodetectors. Compared with pure 2D CdS x Se 1−x nanosheet photodetectors, the photoelectric performance of the PbS/CdS x Se 1−x hybrid nanostructure is enhanced by 3 orders of magnitude under near-infrared (NIR) light illumination and maintains its performance in the visible (Vis) range. The photodetector exhibits a broadband response range from Vis to NIR with an ultrahigh light-to-dark current ratio (3.45 × 10 6 ), a high spectral responsivity (1.45 × 10 3 A/W), and high detectivity (1.05 × 10 15 Jones). The proposed QDs/2D nonlayered hybrid nanostructure-based photodetector paves a promising way for next-generation high-performance broadband optoelectronic devices.