In addition, the detected Eopt values of the ATO NPs were found to increase from 4.07 eV to 4.29 eV with increasing the Sb doping concentration from 0.5% to 50%. The influence of Sb concentration was further investigated by measuring the variations of the WF and conductivity. When the Sb doping level increased, the conductivity initially increased to the optimal value of over 3×105. S cm1 at 10–20% Sb content, which is approximately three orders of magnitude higher than that of pristine SnO2 owing to the sharp increase in hole concentration; however, a deterioration of electrical conductivity is observed at higher Sb doping concentration, ascribed to the further intensified degradation of the crystalline structure and a concomitant decrease in the hole concentration. Meanwhile, a gradual increase in WF from 5.13±0.02 eV for 2% Sb content to 5.32±0.02 eV for 50% Sb content was observed, opening an optimization route to deliberately tune the energy level alignment with a wide range of organic photovoltaic materials. A gradually increasing hole concentration pushes the EF deeper into the ATO gap, leading to a higher WF value. Nevertheless, in a higher doping concentration, a gradual increase in WF still was observed with a decrease of the hole concentration, probably mainly due to the less-conductive surface of ATO NPs Our electronic measurements uniquely evidence SnO2 NPs as non-stoichiometrically n-type doped, which becomes compensational p-type doped upon addition of antimony. Having established a macroscopic model allowing us to understand the properties of SnO2 upon doping with antimony, we wanted to elucidate the interplay of Sb3+ and Sb5+ions and their relevance for doping. If you are looking for high quality, high purity, and cost-effective ATO, or if you require the latest price of ATO, please feel free to email contact mis-asia.