title: Halide-Amine Co-Passivated Indium Phosphide Colloidal Quantum Dots in Tetrahedral Shape.
abstract: Wet chemical synthesis of covalent III-V colloidal quantum dots (CQDs) has been challenging because of uncontrolled surfaces and a poor understanding of surface-ligand interactions. We report a simple acid-free approach to synthesize highly crystalline indium phosphide CQDs in the unique tetrahedral shape by using tris(dimethylamino) phosphine and indium trichloride as the phosphorus and indium precursors, dissolved in oleylamine. Our chemical analyses indicate that both the oleylamine and chloride ligands participate in the stabilization of tetrahedral-shaped InP CQDs covered with cation-rich (111) facets. Based on density functional theory calculations, we propose that fractional dangling electrons of the In-rich (111) surface could be completely passivated by three halide and one primary amine ligands per the (2×2) surface unit, satisfying the 8-electron rule. This halide-amine co-passivation strategy will benefit the synthesis of stable III-V CQDs with controlled surfaces.
authors: Nanomechanical Systems Research Division, Korea Institute of Machinery and Materials, Daejeon, 34103, Korea.
authors: Kyungnam
authors: K
authors: Kim
authors: Graduate School of Nanoscience and Technology, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Korea.
authors: Dongsuk
authors: D
authors: Yoo
authors: Nanomechanical Systems Research Division, Korea Institute of Machinery and Materials, Daejeon, 34103, Korea.|Department of Nanomechatronics, Korea University of Science and Technology (UST), Daejeon, 34113, Korea.
authors: Hyekyoung
authors: H
authors: Choi
authors: Nanomechanical Systems Research Division, Korea Institute of Machinery and Materials, Daejeon, 34103, Korea.
authors: Sudarsan
authors: S
authors: Tamang
authors: Graduate School of Nanoscience and Technology, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Korea.
authors: Jae-Hyeon
authors: JH
authors: Ko
authors: Nanomechanical Systems Research Division, Korea Institute of Machinery and Materials, Daejeon, 34103, Korea.
authors: Sungwoo
authors: S
authors: Kim
authors: Graduate School of Nanoscience and Technology, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Korea. yong.hyun.kim@kaist.ac.kr.
authors: Yong-Hyun
authors: YH
authors: Kim
authors: Nanomechanical Systems Research Division, Korea Institute of Machinery and Materials, Daejeon, 34103, Korea. sjeong@kimm.re.kr.|Department of Nanomechatronics, Korea University of Science and Technology (UST), Daejeon, 34113, Korea. sjeong@kimm.re.kr.
authors: Sohee
authors: S
authors: Jeong
keywords: co-passivation; colloidal quantum dots; halides; indium phosphide; tetrahedral shape