Ultraviolet 3600 spectrophotometer

Powder X-ray diffraction data were obtained from a Bruker D8 Advance diffractometer using graphite-monochromatized CuKα radiation (λ = 1.5406 Å). Transmission electron microscopy images were collected from a JEOL-JEM 2100 F electron microscope. Scanning electron microscopy images were taken on a JEOL-JSM-6701F electron microscope. ¹H and ¹³C NMR spectra were recorded on a Bruker Advance 500 spectrometer at ambient temperature. UV-vis absorption spectra were recorded with a SHIMADZU ultraviolet-3600 spectrophotometer. Electrochemical characterisation of the viologen molecule-modified electrode employed a CS310 potentiostat with a Ag/AgCl/1 M KCl (aq) reference electrode.

Ultraviolet–visible spectra were measured on a SHIMADZU ultraviolet-3600 spectrophotometer. Fourier transform infrared spectroscopy spectra were recorded on a Varian 3100 fourier transform infrared spectrometer. Low-resolution TEM images were taken on a JEOL-1400 transmission electron microscope operating at an acceleration voltage of 100 kV. Scanning electron microscopy was carried out on a FEI NOVA NanoSEM 230 scanning electron microscope operated at 5 kV. Powder X-ray diffraction data was obtained on a Siemens D5005 X-ray diffractometer with Cu Kα radiation (λ=1.5406 Å). The upconversion luminescence spectra were recorded in an Edinburgh FSP920 equipped with a photomultiplier, in conjunction with 980 nm diode laser and a xenon arc lamp (Xe900). The measurement of luminescence lifetime was conducted using a lifetime spectrometer (FSP920, Edinburgh) equipped with a microsecond flash lamp as the excitation source. Upconversion luminescence microscopic images were obtained on an Olympus BX51 microscope with a Nikon DS-Ri1 imaging system adapted to a 980 nm diode laser. Digital photographs were taken with a Nikon D700 camera.