0000000000427419
AUTHOR
Nestor Perea-lopez
Angstrom-Size Defect Creation and Ionic Transport through Pores in Single-Layer MoS2
Atomic-defect engineering in thin membranes provides opportunities for ionic and molecular filtration and analysis. While molecular-dynamics (MD) calculations have been used to model conductance through atomic vacancies, corresponding experiments are lacking. We create sub-nanometer vacancies in suspended single-layer molybdenum disulfide (MoS2) via Ga+ ion irradiation, producing membranes containing ∼300 to 1200 pores with average and maximum diameters of ∼0.5 and ∼1 nm, respectively. Vacancies exhibit missing Mo and S atoms, as shown by aberration-corrected scanning transmission electron microscopy (AC-STEM). The longitudinal acoustic band and defect-related photoluminescence were observe…
(Ga,In)P nanowires grown without intentional catalyst
Abstract We have grown (Ga,In)P nanowires through the MOCVD method without a intentional catalyst. The organometallic precursor triethylgallium ( ( C 2 H 5 ) 3 Ga ) , used as Ga source, is transported by the N 2 gas carrier to the reactor chamber where reacts with the InP vapor pressure producing the nanowires. Two different reactor pressures (70 and 740 Torr) were used leading to nanowires with different In contents. The nanowires are straight or wool-like and exhibit a twinned structure. They emit an intense orange to red color visible even to the naked eyes. Interface tunneling process at Ga 1 − x In x P / Ga 1 − y In y P interfaces ( x ≠ y ) is proposed to explain this efficient light e…