[10p-N403-1~17] 9.2 Nanoparticles, Nanowires and Nanosheets

▲ [10p-N403-11] Size-Dependent Electronic Transport in Lead Sulfide Colloidal Quantum Dots Oriented-Superlattices

〇(D)Ricky Dwi Septianto^1,2, Retno Miranti¹, Nobuhiro Matsushita², Takaaki Hikima³, Yoshihiro Iwasa^1,4, Satria Zulkarnaen Bisri^1,2 (1.RIKEN CEMS, 2.Tokyo Inst. of Tech., 3.RIKEN Sprng-8 Center, 4.Univ. of Tokyo)

Keywords:Quantum dots, Superlattice assembly

Here we demonstrate facile control of lead sulfide (PbS) CQD assemblies to form large-scale superlattice with oriented attachment, in which we successfully elucidate their electronic transport. We varied the size of the QDs that become the building block of the assemblies. The superlattice assemblies were prepared by a modified liquid/air interfacial assembly. The attachment and orientational arrangement of QDs were controlled chemically by choosing the proper solvent to support the ligand removal with ethylenediamine as a stripping agent. Having strongly ordered superlattices, the electronic transport properties of QDs assemblies were evaluated by using ionic-liquid-gating field-effect-transistor (FET). Probing by electric-double-layer (EDL)-induced-gating, the size-dependent bandgap of the QDs assemblies can be observed electronically. This size-dependent electronic-transport shows the high-carrier transporting while the confinement of QDs is still maintained. Therefore, this study reveals the key indicator to significantly enhance the performance of QDs-based electronic device for practical applications.