Auriga fib sem system

Cross sections of the perovskite fibre were characterized by a Zeiss Auriga FIB-SEM system. The UV-Vis spectra of the perovskite QD solutions were measured by a Shimadzu UV-3600 UV/VIS/NIR spectrophotometer. SEM images were obtained by using a FEI Quanta 250FEG system, and AFM images were acquired by a Bruker Multimode 8 AFM system. The PL spectra of the QDs were measured by using an Agilent Cary Eclipse spectrometer. The photodetector characteristics were measured by a Keysight B1500A semiconductor analyser. The EL spectra and L-J-V characteristics were collected by using a Keithley 2400 source metre, a spectroradiometer (Cs-2000, Konica Minolta), and a close-up lens at room temperature. The viscosities of the pure and molecule-doped QD solutions were acquired on a Malvern Rheometer Instrument (Kinexus Lab+, UK). The surface tensions of the pure and molecule-doped QD solutions were measured using a Kibron EZ Pi-Plus tensiometer. The light communication system consisted of an oscilloscope (DSO9254A, Keysight), a 405 nm OBIS laser, an arbitrary waveform generator (33622 A, KEYSIGHT) and a photodiode module (C12702-11, Hamamatsu).

The patterned nanocomposites were fabricated on poly(methyl methacrylate) (PMMA). Initially, PMMA thin films were produced on glass cover slips of 18 mm in diameter. The glass cover slips surfaces were first activated with oxygen plasma (Tepla 600) at 300 W for 5 min to improve the adhesion and then, a solution of PMMA (M_w 120.000, Sigma-Aldrich) on toluene (7.5 wt/v%) was spin-coated at 1000 rpm for 1 min and the resultant film annealed at 100 °C. Subsequently, the films were activated with oxygen plasma (Tepla 600) at 50 W for 1 min and the prepared (0.5 wt/v%) TiO₂ or ZnO NP dispersions spin coated. On the PMMA-NP prepared films, the moth-eye nanocomposite structures were nanoimprinted at 170 °C and 45 bars of pressure for 5 min using an Eitre 3 Nanoimprint lithography system (Obducat Technologies AB) using a PDMS working mould. As control substrates, smooth nanocomposites were prepared following the same conditions but pressed using instead a flat slab of PDMS. The PDMS working mould was obtained by replication of a master nickel mould (HT-AR-02, Temicon) as reported before.^{13 (link)} The nanocomposite substrates were imaged by scanning electron microscopy (SEM) using an Auriga FIB-SEM system (Zeiss) and by atomic force microscopy (Multimode 8 AFM system, Bruker).

Scanning electron microscopy (SEM) images were taken to visualize the attachment of bacteria onto the moth-eye nanocomposites surfaces. Prior imaging, all substrates were fixed following protocols reported before.^{13 (link)} The substrates were sputter-coated with a thin layer of gold and imaged on an Auriga FIB-SEM system (Zeiss).