Huang, Po ChengPo ChengHuangTseng, PinchengPinchengTsengCheng, Yu-TingYu-TingChengTsai, Hsiao-EnHsiao-EnTsaiYIH-SHARNG CHEN2026-04-162026-04-162026-04-01https://scholars.lib.ntu.edu.tw/handle/123456789/737234A miniaturized, nonenzymatic hydrogen sulfide (H2S) sensor has been fabricated on an industrial flexible printed-circuit board (FPCB) using inkjet printing technology. The working electrode comprises a multilayer stack of Ag nanoparticles, multiwall carbon nanotubes (MWCNTs), and Ag, capped with a Nafion-Ru(NH3)3+/2+ 6 anti-interference film. An active reduction-bias cleaning (RBC) scheme is implemented to electrochemically reduce surface silver sulfide (Ag2S) back to metallic silver, thereby mitigating sulfur-induced electrode fouling and preserving sensor sensitivity. The sensor exhibits a linear detection range of 0.05-800 μM, a sensitivity of approximately 251.6 nA · μM-1 · cm-2, and a limit of detection (LOD) of ~0.03 μM, corresponding to a 150% increase in sensitivity and a 75% reduction in LOD, respectively. The signal degradation after 20 consecutive exposures is less than 3.5%. These results demonstrate the potential of this RBC-enabled sensor for reliable, low-cost, real-time biomedical H2S monitoring. © 2001-2012 IEEE.enAntielectrode poisoningflexible hydrogen sulfide (H2S) sensing probeinkjet printingnegative reduction biasnonenzymaticjournal article10.1109/JSEN.2026.3663585