Final answer:
While your approach to measure pH using electrochemistry is innovative, traditional pH meters with glass electrodes already provide a direct and calibrated method to measure pH accurately without requiring the voltage adjustments you describe.
Step-by-step explanation:
Developing a device to measure pH in aqueous solutions using electrochemistry is an innovative idea, but it requires a refined approach to accurately determine the concentration of hydronium ions (H3O+).
Traditional pH meters utilize a glass electrode that measures the potential difference across the electrode pertinent to the pH of the solution. This potential is a direct function of the pH level and typically does not require the gradual increase of voltage you propose as pH meters are already calibrated to convert voltage to pH values.
The use of a standard hydrogen electrode (SHE) as a reference with a defined potential of 0 V and the construction of galvanic cells as seen in various examples show the intricacies involved in such measurements. These setups rely on electrochemical reactions and are complex in their requirement of precise conditions and concentrations. For instance, the oxygen reduction reaction to water or the Zn/Zn2+ couple in a cell setup can illustrate the principle behind the measurement of pH indirectly.
In your proposed setup, isolating one electrode and using a salt bridge are important considerations. However, it may not be straightforward to extract the pH information solely from the onset of current flow. Instead, the glass membrane in commercial pH meters adsorbs protons, and its potential varies systematically with the pH of the solution, allowing for a more accurate and simplified measurement.