In situ spectroscopic characterization of a solution-phase X-type ligand exchange at colloidal lead sulphide quantum dot surfaces.
نویسندگان
چکیده
We employed quantitative NMR spectroscopy and spectrophotometric absorbance titration to study a quantum dot X-type ligand exchange reaction. We find that the exchange is highly cooperative, where at low extents of exchange the change in free energy of the reaction, ΔGXC, is ∼11 kJ mol-1 while at higher extents of exchange ΔGXC saturates to ∼-4 kJ mol-1. A modified Fowler binding isotherm is developed to describe the reaction.
منابع مشابه
Effect of PbS Film Thickness on the Performance of Colloidal Quantum Dot Solar Cells
Colloidal quantum dots offer broad tuning of semiconductor band structure via the quantum size effect. In this paper, we present a detailed investigation on the influence of the thickness of colloidal lead sulfide (PbS) nanocrystals (active layer) to the photovoltaic performance of colloidal quantum dot solar cells. The PbS nanocrystals (QDs) were synthesized in a non-coordinating solvent, 1-oc...
متن کاملEnergy states and exchange energy of coupled double quantum dot in a magnetic field
The ground state energies of two interacting electrons confined in a coupled double quantum dot (DQD) presented in a magnetic field has been calculated by solving the relative Hamiltonian using variational and exact diagonalization methods. The singlet-triplet transitions in the angular momentum and spin of the quantum dot ground state had been shown .We have studied the magnetic field versus c...
متن کاملEnergy states and exchange energy of coupled double quantum dot in a magnetic field
The ground state energies of two interacting electrons confined in a coupled double quantum dot (DQD) presented in a magnetic field has been calculated by solving the relative Hamiltonian using variational and exact diagonalization methods. The singlet-triplet transitions in the angular momentum and spin of the quantum dot ground state had been shown .We have studied the magnetic field versus c...
متن کاملTuning colloidal quantum dot band edge positions through solution-phase surface chemistry modification
Band edge positions of semiconductors determine their functionality in many optoelectronic applications such as photovoltaics, photoelectrochemical cells and light emitting diodes. Here we show that band edge positions of lead sulfide (PbS) colloidal semiconductor nanocrystals, specifically quantum dots (QDs), can be tuned over 2.0 eV through surface chemistry modification. We achieved this rem...
متن کاملIntroducing nanostructure patterns for performance enhancement in PbS colloidal quantum dot solar cells
With attention to the thin film structure of colloidal quantum dot solar cells, in this paper in order to improvement of active layer absorption of them, we have proposed the use of nanostructure pattern for enhancement of their performance. For this purpose we have presented suitable nano hemisphare patterns in colloidal quantum dot solar cells for light trapping in absorption layer. Then with...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Chemical communications
دوره 52 96 شماره
صفحات -
تاریخ انتشار 2016