Voltage tunable super-Nernstian potentiometric sensitivity of InN/InGaN quantum dots

Voltage tuning of the super-Nernstian potentiometric sensitivity of InN/InGaN surface quantum dots is demonstrated. Within a distinct voltage range, the potentiometric sensitivity is tuned from sub-Nernstian sensitivity, continuously over the maximum super-Nernstian and back to the sub-Nernstian sensitivity. This unique voltage tuning is understood by the tuning of the number of electrons bound in the quantum dots, thereby changing the thermodynamic equilibrium state of the quantum dot—electrolyte system, according to the Nernst equation. This redefines the physics of potentiometric sensing to allow the controlled tuning of the sensitivity to the very super-Nernstian maximum and advanced modulated potentiometric sensing is at hand.