基于YAG∶Ce~(3+)荧光材料的中子管靶点表征方法

为实现伴随粒子中子管研究中的小靶点表征,设计了一种基于YAG∶Ce材料的模块化荧光靶体,给出了一种靶点实时监视与测量的方法。利用该方法实现了伴随粒子中子管最小4 mm直径靶点的实验工作。研究中在可更换的荧光靶面上经过激光雕刻阵列化后,能够分辨毫米级甚至亚毫米级的靶点大小。经过长时间高能离子束轰击后的YAG∶Ce材料靶面能够持续发光,未见性能下降,证明YAG∶Ce材料具有良好的耐辐照性能。     

Performance enhancement of ZnO nanowires/PbS quantum dot depleted bulk heterojunction solar cells with an ultrathin Al_2O_3 interlayer

Depleted bulk heterojunction(DBH)PbS quantum dot solar cells(QDSCs),appearing with boosted short-circuit current density(J_(sc)),represent the great potential of solar radiation utilization,but suffer from the problem of increased interfacial charge recombination and reduced open-circuit voltage(V_(oc)).Herein,we report that an insertion of ultrathin Al_2O_3 layer(ca.1.2 A thickness)at the interface of ZnO nanowires(NWs)and Pb S quantum dots(QDs)could remarkably improve the performance of DBH-QDSCs fabricated from them,i.e.,an increase of V_(oc) from 449 mV to 572 mV,Jsc from21.90 mA/cm~2 to 23.98 mA/cm~2,and power conversion efficiency(PCE)from 4.29% to 6.11%.Such an improvement of device performance is ascribed to the significant reduction of the interfacial charge recombination rate,as evidenced by the light intensity dependence on Jsc and Voc,the prolonged electron lifetime,the lowered trap density,and the enlarged recombination activation energy.The present research therefore provides an effective interfacial engineering means to improving the overall performance of DBH-QDSCs,which might also be effective to other types of optoelectronic devices with large interface area.