The design of hierarchical heterostructures that can detect volatile organic compounds (VOCs) at room temperature with good selectivity, sensitivity, and humidity tolerance is an intriguing and practically useful area of research. In this study, Pt@SnS₂/MXene with a 0D@2D/2D hybrid structure was successfully fabricated by selectively etching Ti₃C₂T_x MXene with HF and following this with SnS₂ solvothermal growth and finally decorating with Pt nanoparticles. Decoration of few layered vertically grown SnS₂ nanoflakes with rich active sites provided an electron reservoir that promoted the selectivity, conductivity, and stability of the MXene-based ternary heterostructure during sensing applications. Post-functionalization with trimethoxypropylsilane (TES) formed a monolayer on the ternary heterostructure of Pt@SnS₂/MXene by self-assembly, improved moisture resistance and sensitivity, and maximized sensor durability. Interfacial contact of the TES functionalized mixed metal interface facilitated charge transport and the spectral separation required for NH₃ sensing at room temperature (R_a/R_g = 22.7, 10 ppm NH₃), which was 14.2, 12.6, 8.1, and 3.3-fold greater higher than those of MXene, SnS₂, SnS₂/MXene, and Pt@SnS/MXene, respectively. The functionalized heterostructure exhibited high response, remarkable relative response (98.7%), a low theoretical detection limit (23 ppb), and long-term stability (nearly 30 days). Furthermore, TES functionalization protected the sensor from humidity and the sensor sensitivity was ascribed to a Schottky barrier and p–n junction at the Pt@SnS₂/MXene heterostructure interface. Superior sensing responses were retained at various humidity levels due to the hydrophobicity of TES alkyl chains. In addition, TES captured free electrons on the sensing surface, and thus, maximized the width of the electron depletion layer. The functionalized Pt@SnS₂/MXene heterostructure-based template offers a potential means of constructing highly sensitive and durable gas sensors suitable for practical NH₃ responsive, flexible wearable electronics.

中文翻译：

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设计一种表面功能化的 Pt@SnS2/Ti3C2Tx MXene 传感器，在室温下具有耐湿性和高灵敏度，用于 NH3 检测


设计能够在室温下检测挥发性有机化合物 （VOCs） 并具有良好的选择性、灵敏度和湿度耐受性的分层异质结构是一个有趣且实用的研究领域。在这项研究中，通过用 HF 选择性蚀刻 Ti₃C₂T_x MXene，然后用 SnS₂ 溶剂热生长，最后用 Pt 纳米颗粒装饰，成功制备了具有 0D@2D/2D 杂化结构的 Pt@SnS₂/MXene。用丰富的活性位点装饰少数分层垂直生长的 SnS₂ 纳米薄片提供了一个电子储存器，在传感应用中促进了基于 MXene 的三元异质结构的选择性、导电性和稳定性。三甲氧基丙基硅烷 （TES） 的后功能化通过自组装在 Pt@SnS₂/MXene 的三元异质结构上形成单层，提高了防潮性和灵敏度，并最大限度地提高了传感器的耐用性。TES 功能化混合金属界面的界面接触促进了室温下 NH₃ 传感所需的电荷传输和光谱分离 （R_a/R_g = 22.7， 10 ppm NH₃），比 MXene、SnS₂、SnS₂ 高 14.2、12.6、8.1 和 3.3 倍/MXene 和 Pt@SnS/MXene。功能化异质结构表现出高响应、显著的相对响应 （98.7%） 、低理论检出限 （23 ppb） 和长期稳定性 （近 30 天）。 此外，TES 功能化保护传感器免受湿度影响，传感器灵敏度归因于 Pt@SnS₂/MXene 异质结构界面处的肖特基势垒和 p-n 结。由于 TES 烷基链的疏水性，在各种湿度水平下都保留了出色的传感响应。此外，TES 在传感表面上捕获了自由电子，从而最大限度地提高了电子耗尽层的宽度。基于功能化 Pt@SnS₂/MXene 异质结构的模板为构建适用于实用 NH₃ 响应式柔性可穿戴电子设备的高灵敏度和耐用气体传感器提供了一种潜在的方法。