DPV measurements were performed in a nitrogen-filled glovebox under inert conditions with a CHI760E Bipotentiostat (CH-Instruments). The PbS experiments were performed using a full-glass gas-tight electrochemical cell, which was additionally placed in a faraday cage to shield from environmental electromagnetic radiation. The used three-electrode setup consisted of a 3 mm diameter glassy carbon disc electrode (Metrohm 6.1204.300 GC) as a working electrode, a 1 mm diameter coiled platinum wire as a counter electrode, and a Haber-Luggin double-reference electrode composed of an Ag/Ag + system (1 mm diameter silver wire in a 0.01 M AgClO 4 solution in 0.1 M TBAHFP/MeCN), which was capacitively coupled (10 nF) to a Pt wire which was immersed into the electrolyte next to the capillary opening. To prevent contaminations of the electrolyte within the sample chamber by the reference electrode solution, an additional frit filled with 0.1 M TBAHFP/MeCN was inserted between the Haber Luggin capillary and the reference electrode compartment. The sample chamber of the electrochemical cell was filled with 12 mL of 0.1 M TBAHFP/MeCN. Measurements were carried out starting at the OCP of the blank GC electrode to -2.8 V in reductive, and to 2 V in oxidative direction.