核壳结构Au@SnO2的制备及其低温下的正丁醇气敏性能

以SnCl₄·5H₂O和HAuCl₄·3H₂O为原料，以L-半胱氨酸为连接剂，通过水热法制备Au@SnO₂核壳结构纳米颗粒。由透射电子显微镜和X射线衍射结果发现二氧化锡（SnO₂）与金（Au）颗粒的平均粒径分别为4.9 nm和10.5 nm。SnO₂颗粒堆积在Au核表面形成了具有多孔壳结构的复合材料，比表面积达到178.82 m²/g，总孔隙体积为0.165 1 cm³/g。Au@SnO₂核壳结构的存在使得传感器对正丁醇具有优异的气敏性能，在80 ℃时的灵敏度达到8 669.15，检测极限达到3.9×10^-3 g/m³，显著提高了SnO₂的灵敏度，并降低了最佳工作温度。

Preparation of Au@SnO2 Core-Shell Structure and Its n-Butanol Gas Sensing Properties at Low Temperature

The Au@SnO₂ core-shell nanoparticles were prepared by hydrothermal method using SnCl₄·5H₂O and HAuCl₄·3H₂O as raw materials and L-cysteine as a linking agent. Transmission electron microscopy and X-ray diffraction results show that the average particle sizes of stannic oxide and gold particles are 4.9 nm and 10.5 nm，respectively. The stannic oxide particles pile up on the surface of the gold core，forming a porous shell structure. The specific surface area of Au@SnO₂ reaches 178.82 m²/g，and the total pore volume is 0.165 1 cm³/g. The presence of Au@SnO₂ core-shell structure makes the sensor have excellent gas sensitivity to n-butanol. The sensitivity and the detection limit reach 8 669.15 and 3.9×10^-3 g/m³ respectively at 80 ℃，which significantly improves the sensitivity of stannic oxide and decreases the optimal operating temperature.