P-type Ag-LaFeO₃ (AL) is a promising gas-sensing material owing to its large surface area, rich active oxygen lattice, good thermostability, controllable structure and strong reducibility. While the operating temperature of which is high. In this study, B, N, S and Cl doped graphene quantum dots (GQD) were prepared with a simple liquid-phase exfoliation method and with which decorated AL in order to low the operating temperature of AL. The sensors based on the doped GQD operated at room temperature and showed affinity toward different volatile organic compounds (VOCs). B-GQD revealed p-type semiconductor property and reduced the operating temperature of AL markedly form 90 °C to 55 °C when composite with it because of the synergy effect. Undoped GQD and N, S, Cl doped GQD showed n-type semiconductor property and oppositely increased the operating temperature of AL to different extent when composite with AL. That is, the more electrons in the outer layer of the doped element, the higher the temperature of GQD/AL composite rise. Thus the gas-sensing properties of B-GQD/AL composite was further researched, the results showed that the composite possessed high sensitivity, good selectivity, good stability and low operating temperature to low concentration of formaldehyde.

P型Ag-LaFeO ₃（AL）由于其较大的表面积，丰富的活性氧晶格，良好的热稳定性，可控的结构和强大的还原性，是一种很有前途的气体传感材料。而其工作温度较高。在这项研究中，B，N，S和Cl掺杂的石墨烯量子点（GQD）是通过简单的液相剥离方法制备的，并用AL装饰以降低AL的工作温度。基于掺杂GQD的传感器在室温下运行，对不同的挥发性有机化合物（VOC）表现出亲和力。B-GQD表现出p型半导体特性，并且由于其协同作用，将AL的工作温度从90°C显着降低到55°C。未掺杂的GQD和N，S，掺Cl的GQD表现出n型半导体特性，当与AL复合时，相反地提高了AL的工作温度。即，掺杂元素的外层中的电子越多，GQD / AL复合材料的上升温度越高。因此，对B-GQD / AL复合材料的气敏性能进行了进一步的研究，结果表明该复合材料具有高灵敏度，选择性好，稳定性好，对甲醛浓度低的工作温度低的特点。