A low-cost arduino-based pulsed constant-current platform for electrochemical nanostructure synthesis.

Pulsed-current electrodeposition is widely used to control nucleation and growth during the electrochemical synthesis of metallic nanostructures; however, reproducible implementation commonly requires programmable potentiostats or galvanostats, which can be costly or inaccessible for parallel experimentation. This study introduces a low-cost Arduino-based pulsed constant-current platform designed for low-voltage electrodeposition. The system incorporates a 12-bit MCP4725 digital-to-analog converter to define the current setpoint, while an MCP602 operational amplifier drives an IRLZ34N MOSFET in a low-side feedback configuration using a 10 Ω shunt resistor. A 2N2222 transistor actively clamps the MOSFET gate during OFF periods to minimize residual conduction between pulses. Standalone firmware enables direct configuration of ON time, OFF time, cycle number, and current through a 20 × 4 IC LCD and three push buttons, without requiring an external computer during operation. Electrical evaluation from 0.50 to 40.00 mA using a test LED load showed a highly linear relationship between programmed and multimeter-indicated current, with R2 = 0.9998 and a maximum observed difference of 0.80 mA. Pulse timing and OFF-state behavior were confirmed by oscilloscope monitoring. Beyond electrical testing, the platform was validated through Ag electrodeposition protocols used to fabricate TiO2/Ag SERS substrates, including Ag nanoparticles and 3D Ag dendrites, with analytical performance within the range reported for established SERS architectures. The proposed hardware offers an accessible, reproducible, and open-source solution for laboratories requiring programmable pulsed-current capability for low-voltage electrochemical nanostructure synthesis.