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To achieve fully-solution processed n-i-p perovskite solar cells (PSCs), jet-sprayed silver nanowires (AgNWs) are used to replace vacuum-deposited Ag film as the top electrode of n-i-p structure PSCs. AgNWs are covered with a layer of polyvinylpyrrolidone (PVP) because of the addition of PVP during the growth process of AgNWs. This PVP will deteriorate the conductivity of AgNWs and become a charge extraction barrier as an electrode of a PSC. A low temperature (<40 °C) atmospheric-pressure dielectric-barrier-discharge-jet (DBDjet) is used to post-treat AgNWs after completing the fabrication of n-i-p PSCs. The average cell efficiency improved from 9.069% (without DBDjet treatment) to 12.09% (DBDjet with scan rate of 0.5 cm s−1), and the best performing cell achieves efficiency of 14.037% (DBDjet with scan rate of 1 cm s−1). DBDjet plasma treatment removes PVP, improving the interfacial contacts among AgNWs and between AgNWs layer and hole transport layer; this in turn increases the cell efficiency. Sheet resistance measurement, X-ray photoelectron spectroscopy, water contact angle measurement, and electrochemical impedance spectroscopy all show evidence of the removal of the PVP layer by DBDjet plasma treatment.

A detailed piezoreflectance (PzR) study of an Fe-containing silicon carbon nitride crystalline film in the temperature range between 15 and 580 K was performed. From the line shape fit of the PzR spectra, the impurity to band and the direct band-to-band transition energies which are denoted as Ei and Egd, respectively, at various temperatures were accurately determined. The parameters that describe the temperature dependence of Ei and Egd are evaluated and discussed.

We vary the substrate temperature by adjusting the nitrogen flow rate and jet-substrate distance during nitrogen atmospheric-pressure plasma jet (APPJ) processing of screen-printed reduced graphene oxides (rGOs) on carbon cloth. The APPJ-processed rGOs on carbon cloth are then used as electrodes for supercapacitors. Increasing the nitrogen flow rate could reduce the gas temperature and enhance the reactivity of the reactive plasma species. Typically, lowering the temperature slows down the chemical reaction; however, increased reactivity of the reactive plasma species at the same jetsubstrate distance could compensate the temperature effect. A nitrogen APPJ could improve the wettability of the screen-printed rGOs on carbon cloth. We found that 20-s APPJ treatment increases the areal capacitance from 6.2 mF cm −2 (without APPJ treatment) to 22.4 mF cm −2 (700°C, 30 slm), as evaluated by galvanostatic charging/discharging (GCD) measurements under a constant current of 0.25 mA. Further, 20-s nitrogen APPJ processing at temperatures of ∼600°C-700°C could obtain the best areal capacitance value. The capacitance value of the fabricated flexible rGO supercapacitor remains at similar level after 1000-cycle mechanical bending test with a bending radius of 5 mm.