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We report herein a means of transforming TiO 2 nanotube arrays (TNAs) from an amorphous state to an anatase crystal state (denoted as ∗ TNAs), and present a single-step synthetic route for preparing CdS quantum dots (CdS QDs) as well as reduced graphene oxide (rGO) through gamma-ray irradiation. The as-prepared ∗ TNAs, CdS QDs, and rGO, which had all been subjected to gamma-ray irradiation, were then assembled together to produce the desired heterojunction (denoted as CdS QDs/rGO- ∗ TNAs). X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), ultraviolet/visible diffuse-reflectance spectroscopy (UV/Vis DRS), Fourier-transform infrared spectroscopy (FTIR), micro-Raman spectrometry (RS), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS) have been applied to characterize the appearance and performance of this photocatalyst. The photocatalytic activity of CdS QDs/rGO- ∗ TNAs towards ethylene degradation has been measured by placing it in a simulated cold-storage environment, the temperature and humidity of which were set at about 3 ± 1 °C and 75–90%, respectively. The results showed that the rate constant ( K ) of ethylene degradation could reach up to 1.07 × 10 −3  min −1 with CdS QDs/rGO- ∗ TNAs, as compared to 2.30 × 10 −4  min −1 with ∗ TNAs and 6.25 × 10 −4  min −1 with CdS QDs- ∗ TNAs, indicating that the constructed CdS QDs/rGO- ∗ TNAs constitutes a promising photocatalyst for ethylene removal in a cold storage environment. [ABSTRACT FROM AUTHOR]

• Flower-like ZnIn 2 S 4 coupled with black phosphorus (BP) as efficient photocatalyst. • BP and photo-deposited Pt played a synergistic role in enhancing photocatalytic H 2 evolution. • 0.5%Pt/0.5%BP/ZnIn 2 S 4 showed the best H 2 production efficiency at 1278 μmol/g/h. • Superior recycling stability of more than 4 cycles for solar hydrogen evolution. To make persistent efforts at enhancing hydrogen evolution driven by solar energy, this work, for the first time, had introduced flower-like ZnIn 2 S 4 coupled with black phosphorus (BP) as efficient photocatalyst for hydrogen evolution with photo-deposited Pt assisted under visible light irradiation. The hydrogen evolution efficiency of BP, ZnIn 2 S 4 , 0.5%BP/ZnIn 2 S 4 , 0.5%Pt/BP, 0.5%Pt/ZnIn 2 S 4 and 0.5%Pt/0.5%BP/ZnIn 2 S 4 photocatalysts were successively conducted and results showed that both BP and Pt played an important role in enhancing the photocatalytic hydrogen evolution rate. Therefore, the ternary 0.5%Pt/0.5%BP/ZnIn 2 S 4 composite exhibited the strongest hydrogen production efficiency at 1278 μmol/g/h, about 10 times higher than that of pristine ZnIn 2 S 4 (131 μmol/g/h) and represented a highly stable characteristic after suffering four recycles. The promoting hydrogen evolution of ternary photocatalyst could be ascribed to the unique bandgap and larger two-dimensional plane structure of BP, which provided abundant landing sites for the anchor of flower-like ZnIn 2 S 4 , thus leading to a well-inhibited recombination and efficient separation of photogenerated electrons and hole pairs between ZnIn 2 S 4 and BP. The remarkable photocatalytic hydrogen evolution performance and prominent stability all indicated that 0.5%Pt/0.5%BP/ZnIn 2 S 4 was a promising photocatalyst candidate for solar hydrogen production. [ABSTRACT FROM AUTHOR]