First-Principles Study of the Electron–Hole Recombination Rate at the Interface of the CdSe Quantum Dot and TiO<sub>2</sub> Substrate

Du, Ning; Cui, Yingqi; Zhang, Li; Yang, Mingli

doi:10.1021/acs.jpcc.1c00970

Cited by 11 publications

(7 citation statements)

References 61 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this research, the computational methods are very similar to those in the previous studies . All the calculations were performed with the Dmol in the Materials Studio using the DFT. − The GGA (generalized gradient approximation)–PBE (Perdew–Burke–Ernzerhof method) functional was used to describe the electron exchange–correlation potential. The double numerical polarized basis set with polarization functions was used to described the wave functions of the valence electron, and a real space cutoff of 0.45 nm was used.…”

Section: Methodsmentioning

confidence: 99%

Mechanism of the Heterogeneous Reduction of NO on a Sodium-Doped Char Surface: A First-Principles Study

et al. 2021

View full text Add to dashboard Cite

Sodium in high-alkali coal facilitates the heterogeneous reduction of nitrogen oxides on char surfaces. However, the reaction mechanism is unclear. In this paper, the effect of sodium on the reaction path of the char heterogeneous reduction of NO was analyzed based on the first-principles study using an armchair char model and a zigzag char model separately. Four reaction paths were obtained, and the most likely reaction path was found by comparison. The highest energy barriers of the reduction reactions were reduced to some extent by doping with the sodium atom. The doped sodium atom had a significant effect on the heterogeneous reduction reactions on the surface of the armchair char and had little effect on the surface of the zigzag char. However, a comprehensive analysis showed that the reactivity of the zigzag model is better than that of the armchair model. From the thermodynamic analysis, the addition of the sodium atom could change the reaction from nonspontaneous to spontaneous. After the completion of the reaction, the oxygen atom would be immobilized on the char structure surface, which will have an effect on the subsequent reaction. This study revealed the effect of the sodium atom on the reaction mechanism of the char heterogeneous reduction of NO and helped perfect the mechanism of the char heterogeneous reduction of NO.

show abstract

Section: Methodsmentioning

confidence: 99%

Mechanism of the Heterogeneous Reduction of NO on a Sodium-Doped Char Surface: A First-Principles Study

et al. 2021

View full text Add to dashboard Cite

show abstract

“…(CdSe) 33 and (CdSe) 34 are the representatives of II–VI QDs, which possess high stability and have been characterized in many theoretical and experimental studies. − Aiming to interpret special features in the spectral diffusion of QDs, we performed first-principles calculations in this work to address the shifts in the absorption and emission edges of (CdSe) 33 and (CdSe) 34 under external fields. Based on the previously established polarization model, a two-process four-state model is proposed to address the relationship of spectral diffusion with electron–hole separation.…”

Section: Introductionmentioning

confidence: 99%

Effect of Electron–Hole Separation on the Spectral Diffusion of Small-Sized CdSe Quantum Dots under an External Electric Field

et al. 2023

Self Cite

View full text Add to dashboard Cite

Spectral diffusion occurs in semiconductor quantum dots (QDs) under an external electric field, resulting from the transition energy shift of one single dot during optical absorption and emission processes. The classical electric polarization model fails to interpret the spectral diffusion in some cases when strong quantum confinement Stark effects and large Stokes shifts exist in the small-sized QDs. Based on the two-process (optical absorption and emission) four-state (the ground-and excited-states involved in each process) model, the field-induced spectral shifts of the (CdSe) 33 and (CdSe) 34 structures, which are computed with the first-principles calculations, are well fitted by the dipole moment and static polarizability changes in the separate processes. Furthermore, the linear and the quadratic variations of the field-induced spectral shifts are interpreted with the compressible and the incompressible electron−hole separation distances, which are computed from the Kohn−Sham levels involved in the excited states. Our study provides the direct pieces of evidence on the hypothesis summarized experimentally that the electron transition energy increases with the decreasing electron−hole separation. As a result, the spectral shifts of one single QD, as well as the spectral diffusion of QDs, are then adjustable by tuning the direction and strength of the external field.

show abstract

“…If transparent solar cell glass can be commercialized, the light that has not been converted into electricity can be used for lighting. With the increasing demand for solar cells, the investment in the research and development of new transparent QDSSCs is also increasing. , The slow development of transparent photoanodes has become a problem that must be faced. TiO 2 is a commonly used wide-band-gap semiconductor in solar cell photoanodes .…”

Section: Introductionmentioning

confidence: 99%

Interface Regulation and Properties of Transparent Anatase TiO₂ Photoanode Quantum Dot-Sensitized Solar Cells

Jiang,

Dai,

Xie

et al. 2023

ACS Appl. Nano Mater.

View full text Add to dashboard Cite

In this work, we propose a strategy that is different from the traditional technology of increasing the specific area of the TiO 2 film to improve the carrying capacity of QDs in QDSSCs. Transparent anatase TiO 2 films are prepared by improving the optical transmittance of the photoanode TiO 2 film so that the attached QDs can capture more photons and improve the efficiency of utilizing QDs. This QDSSC preparation technology sacrifices part of QDs loading but improves the utilization efficiency of QDs. At the same time, the transparent bulk TiO 2 film decreases the transmission distance of photogenerated charge carriers, reduces the cross-interface transport, optimizes the transmission path, and reduces the carrier capture composite rate compared with the TiO 2 particle film. Therefore, it not only increases the V oc , FF, and PCE of QDSSCs to 0.628 V, 54.7, and 6.166%, respectively, but also has greater transparency. It meets the demand for solar cell transparency in practical applications and has a wider range of applications and better aesthetics. The mechanism simulation and theoretical analysis of photothermal conversion and electromagnetic mechanism show that the barrier of carrier transfer in bulk transparent anatase TiO 2 is lower than the physical barrier between anatase TiO 2 NPs. The advantages of the anatase transparent TiO 2 film in the process of photogenerated charge carrier transmission are verified. It provides an idea for the development of QDSSCs. It also brings the technology of transparent TiO 2 film to related fields.

show abstract

First-Principles Study of the Electron–Hole Recombination Rate at the Interface of the CdSe Quantum Dot and TiO₂ Substrate

Cited by 11 publications

References 61 publications

Mechanism of the Heterogeneous Reduction of NO on a Sodium-Doped Char Surface: A First-Principles Study

Mechanism of the Heterogeneous Reduction of NO on a Sodium-Doped Char Surface: A First-Principles Study

Effect of Electron–Hole Separation on the Spectral Diffusion of Small-Sized CdSe Quantum Dots under an External Electric Field

Interface Regulation and Properties of Transparent Anatase TiO₂ Photoanode Quantum Dot-Sensitized Solar Cells

Contact Info

Product

Resources

About

First-Principles Study of the Electron–Hole Recombination Rate at the Interface of the CdSe Quantum Dot and TiO2 Substrate

Cited by 11 publications

References 61 publications

Mechanism of the Heterogeneous Reduction of NO on a Sodium-Doped Char Surface: A First-Principles Study

Mechanism of the Heterogeneous Reduction of NO on a Sodium-Doped Char Surface: A First-Principles Study

Effect of Electron–Hole Separation on the Spectral Diffusion of Small-Sized CdSe Quantum Dots under an External Electric Field

Interface Regulation and Properties of Transparent Anatase TiO2 Photoanode Quantum Dot-Sensitized Solar Cells

Contact Info

Product

Resources

About

First-Principles Study of the Electron–Hole Recombination Rate at the Interface of the CdSe Quantum Dot and TiO₂ Substrate

Interface Regulation and Properties of Transparent Anatase TiO₂ Photoanode Quantum Dot-Sensitized Solar Cells