黑磷烯尺寸对黑磷烯/羟基磷灰石混合物气敏性能的影响

Effect of size of black phosphorene on gas sensitivity of black phosphorene/hydroxyapatite hybrid

采用水热法制备短棒状羟基磷灰石(HA),通过液相剥离法制备黑磷烯(black phosphorene,BP),并采用不同的离心速率分离出具有不同尺寸的BP。制备BP质量分数为7.0%的BP/HA混合物,用X射线衍射仪、扫描电镜、透射电镜、原子力显微镜和拉曼光谱对混合物的物相组成、微观形貌和结构进行表征,同时使用气体传感系统研究纯HA以及含有不同尺寸BP的BP/HA混合物的气体传感特性。结果表明,加入BP可显著提高HA对氨气的响应,BP的尺寸越小,对HA气敏性能的提升越大。其中BP-10000/HA对浓度(气敏实验所用空气中氨气的体积分数)为100×10^(-6)的氨气的响应高达58.7%,当氨气浓度上升到1 000×10^(-6)后,响应高达98.3%。BP尺寸越小,气敏性能越好,可能是由于具有更大的比表面积,因而具备更多的活性位点。总之,BP可显著提升HA的气敏性能,BP/HA混合物是一种很有前途的室温气敏材料。

In this work,rod-shaped hydroxyapatite (HA) was prepared by hydrothermal method,and black phosphorene(BP) with different sizes was prepared by liquid-phase exfoliation and separated by adopting different centrifugation speed.BP/HA hybrid was prepared with BP at 7.0%mass fraction.The phase composition,micro-morphology and structure of BP/HA were characterized using X-ray diffraction,scanning electron microscopy,transmission electron microscopy,atomic force microscopy and Raman spectroscopy.The gas sensing properties of pure HA and BP/HA with different sizes of BP were investigated using a gas sensing system.The results show that the addition of BP significantly improves the response of HA to ammonia,and the gas-sensing performance of HA is improved the most with the addition of BP with smaller size.Among them,the response of BP-10000/HA to the ammonia concentration of 100×10^(-6)is as high as 58.7%,and when the ammonia concentration isincreased to 1 000×10^(-6),the response is as high as 98.3%.The smaller the size of BP,the better the gas sensing performance may be due to its larger specific surface area and thus more active sites.In conclusion,BP can significantly improve the gas sensitivity of HA,and BP/HA is a promising gas sensitive material at room temperature.