The potential of two-dimensional group-IV monochalcogenides MX (M = Ge, Sn; X = S, Se) as sensitive materials for gas sensors is being greatly explored. In this work, an exploration combined experimental and theoretical on pure SnS, Ag-doped and Ag-functionalized SnS for promising ethanol sensing performance is performed. A one-step solvothermal process was employed to synthesize pure SnS and Ag-doped SnS, and an environmentally friendly glucose induction method was used to prepare Ag-functionalized SnS. The sensing measurements towards 1–10 ppm ethanol exposure indicate that the doping and functionalization of Ag are both viable strategies in enhancing the sensing performance of SnS, and Ag-functionalization seems to be more effective. Compared with pure SnS, the sensing response of Ag-doped SnS to 10 ppm ethanol is revealed to increase by approximately 3.3 times, and that of Ag-functionalized SnS is about 4.4. It is also revealed that the sensors based on Ag-doped and Ag-functionalized SnS could show greatly improved selectivity. Further first-principles calculations on gas molecules adsorbed on the substrates was performed to demonstrate the enhanced sensing response and selectivity. It is clarified theoretically that the incorporation of Ag atoms could enhance the adsorption capability and charger transfer of the SnS surface to ethanol molecules, thus achieving obvious response enhancement and selectivity improvement. The present work demonstrates that Ag modification, including Ag-doping and Ag-functionalization, is highly effective for enhancing the response and selectivity of SnS towards ethanol vapor, and the modified sensors are promising for highly sensitive ethanol detection with low power consumption.

二维IV类单硫族化物MX（M = Ge，Sn; X = S，Se）作为气体传感器的敏感材料的潜力正在得到极大的探索。在这项工作中，对纯SnS，Ag掺杂和Ag功能化SnS进行了实验和理论相结合的探索，以实现有希望的乙醇传感性能。采用一步溶剂热法合成纯SnS和掺Ag的SnS，采用环境友好的葡萄糖诱导法制备Ag官能化的SnS。对1-10 ppm乙醇暴露的感测结果表明，Ag的掺杂和功能化都是增强SnS感测性能的可行策略，而Ag官能化似乎更有效。与纯锡锡相比，结果表明，Ag掺杂的SnS对10 ppm乙醇的感测响应提高了约3.3倍，而Ag官能化的SnS的感测响应提高了约4.4倍。还揭示了基于Ag掺杂和Ag官能化的SnS的传感器可以显示出大大提高的选择性。对吸附在基板上的气体分子进行了进一步的第一性原理计算，以证明增强的传感响应和选择性。从理论上讲，掺入Ag原子可以增强SnS表面向乙醇分子的吸附能力和电荷转移，从而实现明显的响应增强和选择性提高。目前的工作表明，Ag改性包括Ag掺杂和Ag功能化，