Vsp 300 potentiostat galvanostat

A pellet of the Li_3.3SnS_3.3Cl_0.7 powder was made by uniaxial pressing 30 mg of powder in a 5 mm diameter cylindrical steel die at a pressure of 125 MPa. A relative density of 80% was obtained by this method. Au electrodes were subsequently sputter coated onto both the faces of the pellet using a Q150R Plus—Rotary Pumped Coater. A.C. impedance measurements were performed using a custom-built sample holder, in the temperature range 25–125 °C, using an impedance analyser (Keysight Technologies E4990A) in the frequency range from 12 MHz to 20 Hz (with an amplitude of 50 mV). All procedures and measurements were carried out in an Ar-filled glovebox to avoid sample decomposition in the air. For measurements at a lower frequency, AC impedance was collected from 3 MHz to 1 mHz with a voltage amplitude of 100 mV using a Biologic VSP-300 potentiostat/galvanostat on a second pellet. This second measurement was made to visualize the blocking electrode response with only access to the total conductivity, while the first measurement was used to determine and dissociate bulk and grain boundary conductivities in the function of temperature (Supplementary Discussion). The impedance spectra were fitted with an equivalent circuit using the ZView2 programme⁶⁵ . Both the measurements give the same total conductivity within error.

Electrical measurements: The impedance of the MMM was measured at open-circuit potential in the SC-ISE setup using a Bio-Logic VSP-300 potentiostat/galvanostat equipped with an impedance channel and a low-current option. A Ag/AgCl (sat. KCl) reference electrode (RE-1CP, Bio-Logic) and a Pt counter-electrode (Bio-Logic) were used. ISE potentials were measured in reference to the same reference electrode using a Burr-Brown INA116 instrumentation amplifier having an input impedance >1015 Ω. The gain was set at 10. The potential from the preamplifier was digitized using a Keysight U2351A USB data acquisition device at 10 kS/s and smoothed by averaging within a half-second window using National Instruments’ LabView programming environment. In order to minimize any hysteresis during the measurements, the ISE was rinsed thoroughly after each run.
UV-vis measurements: The UV-vis spectra were recorded using a dual-beam PerkinElmer Lambda 950 UV/VIS/NIR Spectrometer. Quartz cuvettes with 10 mm optical length were used.