Ammonia gas (NH₃) as a harmful and toxic gas species severely threatens ecological harmony and human health, thus necessitating its sensitive detection at very low dose. In this regard, two-dimensional (2D) nanomaterials have been extensively harnessed as the sensing layers due to the unique merits of large surface area, intriguing layer-dependent electrical behaviors and versatile modifications. Of these 2D candidates, black phosphorus (BP) as a rising representative has attracted considerable attention, whereas undesirably hindered by sluggish response/recovery kinetics and fragile stability. To circumvent these obstacles, we employed titanium dioxide (TiO₂) nanoparticles decorated BP nanosheets as the sensing layer to selectively discern 0.5–30 ppm NH₃ at room temperature (18 ± 2 °C) for the first time. The constituent ratio-optimized BP-TiO₂ sensors exhibited higher response, less baseline drift, shorter response/recovery times, and stronger long-term stability when compared with pure BP counterparts. Enlarged specific surface area, numerous p-n BP-TiO₂ heterojunctions and TiO₂ nanoparticles involved passivation were primarily responsible for these improvements. In summary, the proposed composite sensors have expanded BP-related gas sensing to NH₃ gas for the first time in the experimental perspective simultaneously enriching feasible strategies to improve the operation stability of BP nanosheets.

氨气（NH ₃）作为一种有害有毒气体，严重威胁生态和谐和人类健康，因此需要在极低剂量下对其进行灵敏检测。在这方面，二维 (2D) 纳米材料由于具有大表面积、有趣的层相关电行为和多功能修饰的独特优点而被广泛用作传感层。在这些 2D 候选中，黑磷（BP）作为上升代表引起了相当多的关注，但由于响应/恢复动力学缓慢和不稳定的稳定性而受到不利影响。为了规避这些障碍，我们采用二氧化钛 (TiO ₂ ) 纳米颗粒装饰的 BP 纳米片作为传感层来选择性地识别 0.5-30 ppm NH ₃首次在室温 (18 ± 2 °C) 下进行。与纯BP传感器相比，成分比优化的BP-TiO ₂传感器表现出更高的响应、更小的基线漂移、更短的响应/恢复时间和更强的长期稳定性。增大的比表面积、大量的p - n BP-TiO ₂异质结和涉及钝化的TiO ₂纳米颗粒是这些改进的主要原因。总之，所提出的复合传感器首次从实验的角度将 BP 相关的气体传感扩展到 NH ₃气体，同时丰富了提高 BP 纳米片运行稳定性的可行策略。