Studying the impact of Mg doping on the physical properties of CdS nanocrystals for the fabrication of hybrid solar cells–based organic P3HT : PCBM polymers and inorganic Mg‐doped CdS nanocrystals

Abstract In this work, Mg-doped SnO2 materials with different molar ratios were synthesized by hydrothermal method. Based on the UV-Vis study, band gap (Eg) of the Mg-doped SnO2 is adjusted from 3.76 eV to 3.65 eV via 3 at% concentrations. Results of photovoltaic measurement for dye-sensitized solar cells (DSCs) based on Mg-doped SnO2 film as photoanode indicate that the doping of Mg ions can improve the open-circuit voltage (V oc) of the DSCs, while the electric current density (J sc) of the DSCs is almost unchanged. The cells were measured at 3 days intervals within 24 days after fabrication. Power conversion efficiency (PCE) of 3 at% Mg-doped SnO2 DSCs increases step by step and achieves 4.38% as the cell is tested after 18 days. Electrochemical impedance spectroscopy (EIS) analysis shows that Mg doping enhances light collection, increased the number of photogenerated electrons and inhibits charge recombination.

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Role of Mg Impurity in the Water Adsorption over Low-Index Surfaces of Calcium Silicates: A DFT-D Study

Minerals ◽

10.3390/min10080665 ◽

2020 ◽

Vol 10 (8) ◽

pp. 665

Author(s):

Chongchong Qi ◽

Qiusong Chen ◽

Andy Fourie

Keyword(s):

Water Molecule ◽

Density Functional ◽

Water Adsorption ◽

Dissociative Adsorption ◽

Mg Doping ◽

Calcium Silicates ◽

Single Water Molecule ◽

The Impact ◽

Mg Doped

Calcium silicates are the most predominant phases in ordinary Portland cement, inside which magnesium is one of the momentous impurities. In this work, using the first-principles density functional theory (DFT), the impurity formation energy (Efor) of Mg substituting Ca was calculated. The adsorption energy (Ead) and configuration of the single water molecule over Mg-doped β-dicalcium silicate (β-C2S) and M3-tricalcium silicate (M3-C3S) surfaces were investigated. The obtained Mg-doped results were compared with the pristine results to reveal the impact of Mg doping. The results show that the Efor was positive for all but one of the calcium silicates surfaces (ranged from −0.02 eV to 1.58 eV), indicating the Mg substituting for Ca was not energetically favorable. The Ead of a water molecule on Mg-doped β-C2S surfaces ranged from –0.598 eV to −1.249 eV with the molecular adsorption being the energetically favorable form. In contrast, the Ead on M3-C3S surfaces ranged from −0.699 eV to −4.008 eV and the more energetically favorable adsorption on M3-C3S surfaces was dissociative adsorption. The influence of Mg doping was important since it affected the reactivity of surface Ca/Mg sites, the Ead of the single water adsorption, as well as the adsorption configuration compared with the water adsorption on pristine surfaces.

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Impact of Delay Time before Annealing MAI-PbI2-DMSO Intermediate Phase on Perovskite Film Quality and Photo-Physical Properties

Crystals ◽

10.3390/cryst9030151 ◽

2019 ◽

Vol 9 (3) ◽

pp. 151 ◽

Cited By ~ 3

Author(s):

Yujun Yao ◽

Xiaoping Zou ◽

Jin Cheng ◽

Dan Chen ◽

Chuangchuang Chang ◽

...

Keyword(s):

Solar Cells ◽

Physical Properties ◽

Delay Time ◽

High Performance ◽

Intermediate Phase ◽

Perovskite Solar Cells ◽

Device Performance ◽

Perovskite Layer ◽

The Impact

High-performance perovskite solar cells are strongly dependent on the quality of the perovskite layer. Two-step sequential deposition of CH3NH3PbI3 (MAPbI3) films is widely used to fabricate perovskite solar cells and many factors influence the quality of perovskite films, such as the delay time before annealing the MAI-PbI2-DMSO intermediate phase, which would impact the morphology and photo-physical properties of perovskite thin films. Here, the experimental research indicates that the impact of the delay time before annealing the MAI-PbI2-DMSO intermediate phase on the quality, crystallinity, and photo-physical properties of perovskite film is crucial. During the delay process, the delay time before annealing the MAI-PbI2-DMSO intermediate phase plays an important role in the nucleation process of perovskite grains inside the intermediate phase. With the extension of the delay time before annealing, the quality of the perovskite film deteriorates, thus the photo-physical properties change. We found that after the localized liquid–liquid diffusion of MAI and PbI2, with the extension of the delay time before annealing the MAI-PbI2-DMSO intermediate phase, the nucleation number of the perovskite grains increases and the grain size becomes smaller. Therefore, with the extension of the delay time before annealing, the device performance deteriorates.

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Divulging the role of Cu doped CdS nanocrystals as an electron acceptor in hybrid solar cells

Materials Letters ◽

10.1016/j.matlet.2022.131719 ◽

2022 ◽

pp. 131719

Author(s):

J. Santos-Cruz ◽

Latha Marasamy ◽

Ravichandran Manisekaran ◽

S.A. Mayén- Hernández ◽

F. De Moure-Flores ◽

...

Keyword(s):

Solar Cells ◽

Electron Acceptor ◽

Hybrid Solar Cells ◽

Cds Nanocrystals

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Organic/Inorganic Hybrids for Solar Energy Generation

MRS Bulletin ◽

10.1557/mrs2010.579 ◽

2010 ◽

Vol 35 (6) ◽

pp. 422-428 ◽

Cited By ~ 43

Author(s):

Julia W.P. Hsu ◽

Matthew T. Lloyd

Keyword(s):

Solar Cells ◽

Metal Oxide ◽

Organic Solar Cells ◽

Bulk Heterojunction ◽

Environmental Stability ◽

Attractive Alternative ◽

Hybrid Solar Cells ◽

Oxide Interface ◽

Hybrid Devices ◽

The Impact

AbstractOrganic and hybrid (organic/inorganic) solar cells are an attractive alternative to traditional silicon-based photovoltaics due to low-temperature, solution-based processing and the potential for rapid, easily scalable manufacturing. Using oxide semiconductors, instead of fullerenes, as the electron acceptor and transporter in hybrid solar cells has the added advantages of better environmental stability, higher electron mobility, and the ability to engineer interfacial band offsets and hence the photovoltage. Further improvements to this structure can be made by using metal oxide nanostructures to increase heterojunction areas, similar to bulk heterojunction organic photovoltaics. However, compared to all-organic solar cells, these hybrid devices produce far lower photocurrent, making improvement of the photocurrent the highest priority. This points to a less than optimized polymer/metal oxide interface for carrier separation. In this article, we summarize recent work on examining the polymer structure, electron transfer, and recombination at the polythiophene-ZnO interface in hybrid solar cells. Additionally, the impact of chemical modification at the donor-acceptor interface on the device characteristics is reviewed.

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