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Abstract

Aluminum-doped zinc oxide/platinum/fluorine-doped tin oxide (AZO/Pt/FTO) trilayer films were prepared by sputtering 5-nm-thick Pt layers and 150-nm-thick AZO layers in sequence on commercial FTO glass. The effects of one-step annealing and layer-by-layer annealing on the morphology, structure and photoelectric properties of the AZO/Pt/FTO trilayer films were comparatively analyzed. It is found that the both annealing approaches increased the grain size and improved the crystallinity of the films, leading to enhancement in transmittance and conductivity. However, layer-by-layer annealing led to the formation of quasi-continuous or continuous AZO layers, different from the sparsely distributed AZO particles brought about by one-step annealing, resulting in excellent optical and electrical properties. Specifically, after layer-by-layer annealing at 400 °C for both Pt and AZO layers, the AZO/Pt/FTO trilayer film showed an increase in average transmittance from 71.3% to 85.3% and a decrease in sheet resistance from 7.5 to 5.6 Ω/□, leading to the highest figure of merit of 3.64 × 10−2 Ω−1.

Electrocatalytic oxygen evolution reaction (OER) plays an important role in various renewable energy conversion and storage technologies. Ruthenium complexes with terpyridine (tpy) and bipyridine (bpy) as ligands are considered to be an important catalyst for OER electrocatalysis. Their catalytic performance is affected by substituent groups of the tpy (and bpy) ligands, and is often limited by low current density. Here, we report a Ru‐polypyridine complex covalently anchored to single‐walled carbon nanotubes (SWCNTs) via a tpy ligand to form a hybrid material of SWCNT‐tpyRubpy. Electrocatalytic OER studies have shown that the covalent attachment of the Ru‐polypyridine complexes to SWCNTs avoids noticeable molecular aggregations and increases the conductivity. Compared with that of the SWCNT‐unattached complex, SWCNT‐tpyRubpy exhibits a higher electrocatalytic OER activity with a low onset potential of 1.48 V (vs reversible hydrogen electrode) and a smaller Tafel slope of 109 mV dec−1in alkaline solution. Therefore, the CNT‐hybridization is an effective method for the construction of advanced SWCNT‐based Ru complex electrocatalysts and to understand their catalytic performance. Ru‐polypyridine complex‐based oxygen evolution reaction (OER) catalyst is covalently anchored to single‐walled carbon nanotubes (SWCNTs) to form SWCNTtpyRubpy. It exhibits a higher OER activity with a low onset potential of 1.48 V (vs reversible hydrogen electrode) and a smaller Tafel slope of 109 mV dec−1in alkaline solution, which is attributed to increased conductivity and avoiding noticeable molecular aggregations.

Highly photoactive fullerene-cored star-shaped polyporphyrin incorporated TiO2, ZnCPP-Fullerol@TiO2, was prepared from the immobilization of fullerene-cored star-shaped polyporphyrin nanospheres, produced by the esterification of carboxyl porphyrin with fullerols, on the surface of TiO2via the excess hydroxyl groups of fullerols, and used for rhodamine B degradation under light irradiation. The synthesized catalyst was fully characterized by various techniques, including ultraviolet-visible spectroscopy, fluorescence spectroscopy, X-ray photoelectron spectroscopy (XPS), cyclic voltammetry and thermogravimetric analysis etc. The results demonstrated that the insertion of fullerols in ZnCPP-Fullerol@TiO2produced an enhancement in photocurrent efficiency and the photocatalytic degradation of rhodamine B. The degradation rate of rhodamine B was 94.7% after treatment with light irradiation for 150 min, and the reaction rate constant was k = 0.0193 s−1for ZnCPP-Fullerol@TiO2. This constant was much higher than that of ZnCPP@TiO2(0.00723 s−1) due to the improvement in the separation of electron-hole pairs and the availability of good sites for adsorption and catalysis. Moreover ZnCPP-Fullerol@TiO2exhibits excellent reusability, and a reasonable mechanism for the enhanced reactivity was proposed.