Diamond thermal analyzer

The raw silk and degummed silk fibers were cut into microparticles. Thermal analysis was performed with Perkin-Elmer Diamond Thermal Analyzer (Waltham, MA, USA). The heating rate was 10 °C/min under a flow of N₂, and the test range was 40–600 °C.

The UV–vis spectra of the polymers were performed in the range of 200–800 nm using a Perkin Elmer Lambda-35 UV–vis. spectrophotometer. FT-IR spectra of the polymers were recorded in the range of 2000–400 cm⁻¹ using a Jasco FTIR-430 Fourier transform infrared spectrometer. X-ray diffraction device, Rigaku D/MAX-2200 device, was used to determine the phases and diffraction peaks of PANI and PANI-Zn-PSS polymers. The analysis was carried out with CuKα wavelength radiation beam at room temperature with 10° ≤ 2θ ≤ 80° limit values. The thermal analysis curves (TGA and DTG) were obtained using a PerkinElmer diamond thermal analyzer with a sample size of 5–10 mg and a heating rate of 10 °C min⁻¹ under nitrogen atmosphere. The temperature scanning speed was 10 °C/min. For SEM/EDX measurements, polymer samples were subjected to a thin gold coating by using a FEI brand, Quanta 400 FEG model SEM fine coater. The dry conductivity values of polymers were measured by using a four-probe electrical conductivity measuring device, Entek Electronic, at room temperature. The photocatalytic activities of polymers were measured by using the UV-C tube lamp in a quartz tube (properties of the lamp: 15 W, 41 cm length, 2.5 cm radius Philips Netherlands G15T8 model unfiltered lamp).

Transmission electron microscopy (TEM) was carried out using a 100 kV JEOL JEM-1011 (JEOL, Croissy Sur Seine, France). TEM samples were prepared by depositing on a carbon coated copper grid (400 mesh) a few drops of the nanoparticles suspended in ethanol. High-resolution scanning transmission electron microscopy (HRSTEM) images and Energy-Dispersive X-ray Spectroscopy (EDS) analyses were recorded by TEM-JEM-ARM200F Cold FEG or TEM-JEM-2100F, both equipped with an EDX spectrometer. Elemental analysis was carried out using a Flash EA1112 (Thermo Finnigan 2003, Waltham, MA, USA) apparatus. Magnetic susceptibility of nanoparticle powder samples was measured using a Quantum Design MPMS2 magnetometer (Quantum Design France, les Ulis, France) in the temperature range from 300 to 400 K under a magnetic field of 1 T with a heating/cooling rate of 2 K/min. Optical reflectivity measurements were performed on a stereomicroscope (Motic) equipped with a Moticam 1000 CCD camera (Motic, Wetzlar, Germany). The sample temperature was controlled using a Linkam THMS600 liquid nitrogen cryostat (Linkam Scientific Instruments, London, UK). The temperature change rate was 2 K/min. Thermogravimetric analysis (TGA) data were acquired using a Perkin–Elmer Diamond thermal analyzer (PerkinElmer, Waltham, MA, USA).