Ion-selective light-addressable potentiometric sensor (LAPS) with chalcogenide thin film prepared by pulsed laser deposition

Pb–Ag–As–I–S chalcogenide glass was deposited on the surface of a light-addressable potentiometric sensor (LAPS) by means of the pulsed laser beam deposition (PLD) technique. The deposited layer worked as a Pb2+-ion-sensitive transducer, and the sensor showed Nernstian response with a sensitivity of 29±1 mV/decade. The detection limit of the sensor for Pb2+-ions was 1×10−6 mol/l. The response time does not exceed 50 s for Pb2+-ion concentrations higher than 1×10−3 mol/l, while for lower concentration range the response time increases up to 3–5 min.