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Two novel carbazole-cored small molecules CzC6C8 and CzC8 bearing different side chains and two 3-ethylrhodanine end-capping groups were synthesized and used as electron acceptors in organic solar cells (OSCs). Devices based on these two acceptors showed a high open circuit voltage ( V oc ) about 1 V. Due to more closely molecular stacking and improved film morphology, CzC8 bearing a linear alkyl side chain showed a better photovoltaic performance than CzC6C8 bearing a branched one. CzC8 based OSCs can still exhibit a good performance even though the Δ E LUMO and Δ E HOMO between donor and acceptor are both small. Three polymer donors (PBT, PTB7-Th, and PTFBDT) with a similar LUMO level but various HOMO levels were tested and they all showed good PCE values larger than 4.6%. Among them, PTB7-Th: CzC8 based devices afforded the highest PCE of 4.91% and PTFBDT: CzC8 based ones gave the highest V oc of 1.16 V.

Bismuth-halide-based perovskites could be promising candidates for construction of lead-free and air-stable perovskites solar cells. Herein we report a simple strategy on the fabrication of the Ag3BiBr6 thin films. They were prepared by flexible spin-coating procedure and the solvent of N-butylamine is found to be critical to dissolving AgBr precursor solution under lower room temperatures. Experiment and calculation analysis both reveal it with hexagonal structure. Their physical properties and photovoltaic performance were both characterized. We demonstrate that Ag3BiBr6 films are capable of storing stably over 30 days in air. These results will inspire more research works on developing and applying Ag3BiBr6 beyond solar energy applications.

A thermo-cleavable fullerene derivative was used as an interfacial engineering material in planar perovskite solar cells. The modified TiO2 surface shows exceptional resistance against polar solvent washing and the perovskite film grown on it was of high quality with less pinholes. Consequently, high performance devices without hysteresis have been achieved.

To develop novel hole-transport materials (HTMs) with less synthetic steps is still a great challenge. Here, a small molecule hexakis[4-(N,N-di-p-methoxyphenylamino)phenyl]benzene (F-1) was successfully synthesized by a relatively simple scenario. F-1 exhibits a deep highest occupied molecular orbital energy level of −5.31 eV. Notably, F-1 also features 2 times higher hole mobility of 4.98 × 10–4 cm2 V–1 s–1 than that of the mostly used 2,2′,7,7′-tetrakis(N,N-bis(4-methoxyphenyl)amino)-9,9′-spirobifluorene (spiro-OMeTAD). Consequently, F-1-based perovskite solar cells (PSCs) show markedly improved performance compared with spiro-OMeTAD-based ones. These results indicate such a material can be a promising HTM candidate to boost the overall performance of the PSC.

The robust electroplating settings of a direct-current (dc) plating mode for the co-deposition of Sn–Zn deposits with their composition close to the eutectic point (i.e., Sn–9Zn) from the chloride solutions were achieved and investigated by using experimental strategies, including the fractional factorial design (FFD) and central composite design (CCD) coupled with the response surface methodology (RSM). The temperature of the plating bath, pH, and the metallic ion ratio (i.e., Sn 4+ /Zn 2+ ratio) were found to be the key factors affecting the composition of Sn–Zn deposits in the FFD study. The effects of pH and temperature of the plating solution on the composition of Sn–Zn deposits were examined using a regression model in the CCD study. This model, represented as contour plots, showed that pH 5.0 and temperature = 78 °C were the robust electroplating settings for the co-deposition of the eutectic Sn–Zn alloys, which was independent of the substrates. In addition, based on the robust plating settings, the composition of Sn–Zn alloys could be precisely controlled and predicted by adjusting the composition of the plating baths. From the morphologies and crystalline information, the binary Sn–Zn deposits prepared in this work should belong to heterogeneous alloys.

Tin–zinc deposits with the Zn content varying from 13 to 0 weight percents (wt%) (close to the eutectic point of the Sn–Zn alloy, Sn–9Zn) were electroplated onto iron-coated copper substrates from a near-neutral (pH 5.0), non-cyanide bath. The corrosion parameters, including open-circuit potential–time curves ( E OCP – t ), corrosion potentials ( E CORR ), and corrosion currents ( i CORR ), of this series of materials before and after reflowing in N 2 at 250 °C for 10 min were determined and systemically compared in a brine medium containing 3 wt% NaCl. For the as-prepared deposits, the Sn–5Zn deposit showed an activity very close to but more active than that of Fe in this brine medium. This deposit also exhibited the highest corrosion resistance in the study of electrochemical impedance spectroscopy (EIS). For the reflowed deposits, the anticorrosive ability of Sn–Zn deposits with the Zn content