Bio-inspired pseudo-breathing strategy via a single SnSe/NiO heterojunction for selective H2S sniffing in VSC mixtures.

Artificial olfaction systems face a fundamental trade-off between device simplicity and discriminative capacity, particularly in detecting target gases within complex mixtures. While biological olfaction leverages dynamic sniffing strategies to enhance selectivity with limited receptors, conventional electronic noses rely on sensor arrays, increasing system complexity and power consumption. Here, we report a bio-inspired pseudo-breathing strategy coupled with a single SnSe/NiO heterojunction sensor to achieve highly selective H2S detection in mixed volatile sulfur compounds (VSCs) backgrounds. The heterojunction design creates enhanced surface activity and facilitates rapid charge carrier exchange, enabling fast and sensitive operation at room temperature. By implementing rhythmic adsorption-desorption cycles, we generate time-resolved spectral fingerprints that encode analyte-specific information. Combined with pattern recognition algorithms, this approach allows a single sensor to distinguish H2S from interfering VSCs in binary/ternary mixtures. This work demonstrates a paradigm for the classification of H2S-containing volatile sulfur compound (VSC) mixtures using an actively modulated single sensor, bridging materials innovation and dynamic sensing mechanisms to overcome the limitations of array-based systems.