Инд. авторы:	Forde R., Inerbaev T., Hobbie E.K., Kilin D.S.
Заглавие:	Excited-State Dynamics of a CsPbBr3 Nanocrystal Terminated with Binary Ligands: Sparse Density of States with Giant Spin-Orbit Coupling Suppresses Carrier Cooling
Библ. ссылка:	Forde R., Inerbaev T., Hobbie E.K., Kilin D.S. Excited-State Dynamics of a CsPbBr3 Nanocrystal Terminated with Binary Ligands: Sparse Density of States with Giant Spin-Orbit Coupling Suppresses Carrier Cooling // JOURNAL OF THE AMERICAN CHEMICAL SOCIETY. - 2019. - Vol.141. - Iss. 10. - P.4388-4397. - ISSN 0002-7863.
Внешние системы:	DOI: 10.1021/jacs.8b13385; PubMed: 30712348; SCOPUS: 2-s2.0-85062496697; WoS: 000461537700033;
Реферат:	eng: Fully inorganic lead halide perovskite nano crystals (NCs) are of interest for photovoltaic and light-emitting devices due to optoelectronic properties that can be tuned/optimized via halide composition, surface passivation, doping, and confinement. Compared to bulk materials, certain excited-state properties in NCs can be adjusted by electronic confinement effects such as suppressed hot carrier cooling and I enhanced radiative recombination. Here we use spinor Kohn-Sham orbitals (SKSOs) with spin-orbit coupling (SOC) interaction as a basis to compute excited-state dissipative dynamics simulations on a fully passivated CsPbBr3 NC atomistic model. Redfield theory in the density matrix formalism is used to describe electron-phonon interactions which drive hot carrier cooling and nonradiative recombination (k(nonrad)). Radiative recombination (k(rad)) is calculated through oscillator strengths using SKSO basis. From k(rad) and k(rad) + k(nonrad), we compute a theoretical photoluminescence quantum yield (PLAY) of 53%. Computed rates of hot carrier cooling (k(cooling) approximate to 10(-1) 1/ps) compare favorably with what has been reported in the literature. Interestingly, we observe that hot electron cooling slows down near the band edge, which we attribute to large SOC in the conduction band combined with strong confinement, which creates subgaps above the band edge. This slow carrier cooling could potentially impact hot carrier extraction before complete thermalization in photovoltaics (PVs). Implications of this work suggest that strong/intermediate confined APbX(3) NCs are better suited to applications in PVs due to slower carrier cooling near the conduction band edge, while intermediate/weak confined NCs are more appropriate for light-emitting applications, such as LEDs.
Ключевые слова:	photoluminescence; molecular interaction; molecular dynamics; controlled study; Article; unclassified drug; nanocrystal; cesium lead bromide nanocrystal; Electronic cooling; Radiative recombination; Photoluminescence quantum yields; Optoelectronic properties; Non-radiative recombinations; Excited-state properties; quantum yield; Electronic confinement; Density matrix formalism; Spin dynamics; Perovskite; Passivation; Nanocrystals; Light emission; Lead compounds; Hot carriers; Excited states; Electron-phonon interactions; Conduction bands; Bromine compounds; Excited-state dynamics;
Издано:	2019
Физ. характеристика:	с.4388-4397