Publications by authors named "Fengyou Wang"

Intramolecular hydrogen bonding (H-bonding) involved in the excited-state proton transfer (ESPT) process results in benzophenone derivatives (BPDs) with an excellent ability to passivate defects. However, the BPDs are in a continuing dynamic transition process between the ground state and the excited state under light radiation conditions. The ground-state BPDs may lose their ability to passivate defects, resulting in an increased defect density of the perovskite.

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Aqueous zinc ion batteries (AZIBs) have received a lot of attention in electrochemical energy storage systems for their low cost, environmental compatibility, and good safety. However, cathode materials still face poor material stability and conductivity, which cause poor reversibility and poor rate performance in AZIBs. Herein, a heterogeneous structure combined with cation pre-intercalation strategies was used to prepare a novel CaVO·3HO@NiVO·nHO material (CaNiVO) for high-performance Zn storage.

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Various copper-related defects in the absorption layer have been a key factor impeding the enhancement of the efficiency of CuZnSn(S,Se) (CZTSSe) solar cells. Alkali metal doping is considered to be a good strategy to ameliorate this problem. In this article, Rb-doped CZTSSe (RCZTSSe) thin films were synthesized using the sol-gel technique.

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Effective defect passivation and efficient charge transfer within polycrystalline perovskite grains and corresponding boundaries are necessary to achieve highly efficient perovskite solar cells (PSCs). Herein, focusing on the boundary location of g-CN during the crystallization modulation on perovskite, molecular engineering of 4-carboxyl-3-fluorophenylboronic acid (BF) on g-CN was designed to obtain a novel additive named BFCN. With the help of the strong bonding ability of BF with both g-CN and perovskite and favorable intramolecular charge transfer within BFCN, not only has the crystal quality of perovskite films been improved due to the effective defects passivation, but the charge transfer has also been greatly accelerated due to the formation of additional charge transfer channels on the grain boundaries.

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Overcoming the negative impact of residual ionic liquids (ILs) on perovskite films based on an in-depth understanding of chemical interactions between ionic liquids and preparing perovskite precursor solutions is a great challenge when aiming to simultaneously achieve long-term stability and high efficiency within IL-based perovskite solar cells (PSCs). Herein, 1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF), a type of IL, was introduced into the perovskite precursor solution, and carbon quantum dots (CQDs) were further introduced into the antisolvent to enhance the photovoltaic properties of PSCs. Both ILs and CQDs synergistically manipulate the crystallization process and passivate defects to obtain high-quality perovskite films.

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The smooth and dense light-absorbing layer is an essential factor in polycrystalline solar cells to achieve high photovoltaic performance, while it remains challenging in perovskite solar cells because of the difficulty balancing the speed of crystal nucleation and growth in a solution way. Here, we explored a perovskite nucleation/growth compatible model via manipulating the intermediate complex induced by n-hexylamine (NHA) molecule, guiding us to adjustments perovskite nucleation and growth process. We found that the NHA can act as a gearbox-like molecule to sequentially reduce the perovskite nucleation barrier, promote the nucleation velocity, and retard the perovskite growth simultaneously to obtain uniform perovskite films; correspondingly, this modulation also yields the buried interface with fewer voids and low defects density.

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The attainment of a well-crystallized photo-absorbing layer with minimal defects is crucial for achieving high photovoltaic performance in polycrystalline solar cells. However, in the case of perovskite solar cells (PSCs), precise control over crystallization and elemental distribution through solution processing remains a challenge. In this study, we propose the use of a multifunctional molecule, α-amino-γ-butyrolactone (ABL), as a modulator to simultaneously enhance crystallization and passivate defects, thereby improving film quality and deactivating nonradiative recombination centers in the perovskite absorber.

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N-glycosylation has been revealed to be tightly associated with cancer metastasis. As a key transferase that catalyzes the formation of β1,4 N-acetylglucosamine (β1,4GlcNAc) branches on the mannose core of N-glycans, N-acetylglucosaminyltransferase IVa (GnT-IVa) has been reported to be involved in hepatocellular carcinoma (HCC) metastasis by forming N-glycans; however, the underlying mechanisms are largely unknown. In the current study, we found that GnT-IVa was upregulated in HCC tissues and positively correlated with worse outcomes in HCC patients.

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(CR) is the dry rhizome of L., a Cyperaceae plant. It has a long history of clinical medication and is known as the "holy medicine" of gynecology.

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CuNi·Zn·Sn(S,Se) (CNZTSSe) films were synthesized on Mo-coated glass substrates by the simple sol-gel means combined with the selenization process, and CNZTSSe-based solar cells were successfully prepared. The effects of selenization temperature on the performance and the photoelectric conversion efficiency (PCE) of the solar cells were systematically studied. The results show that the crystallinity of films increases as the selenization temperature raises based on nickel (Ni) doping.

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To compensate for the photoelectric losses of planar heterojunction perovskite solar cells (PSCs), the development of high-quality textured absorbers with excellent light-harvesting ability and carrier extraction/transfer efficiency is of great significance to achieve a high-efficiency stable photovoltaic output. In this paper, we propose an in situ growth passivation technique to construct high-performance textured absorbers by adding a 2-amino-4-chlorophenol (AC) modifier consisting of multiple groups during the growth of textured perovskite. Initially, according to the Ostwald ripening mechanism, the strongly polar dimethylformamide (DMF) was used as the etchant to systematically study its synergistic effect on the morphology evolution, crystallization kinetics, light-trapping capability, and photovoltaic loss of textured absorbers.

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An electron transport layer (ETL) with excellent conductivity and suitable band alignment plays a key role in accelerating charge extraction and transfer for achieving highly efficient planar perovskite solar cells (PSCs). Herein, a novel diluted-cadmium sulfide quantum dot (CdS QD)-assisted SnO ETL has been developed with a low-temperature fabrication process. The slight addition of CdS QDs first enhances the crystallinity and flatness of SnO ETLs so that it provides a promising workstation to obtain high-quality perovskite absorption layers.

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The preferred orientation of crystalline films in hybrid perovskite materials is known to influence the performance of perovskite solar cells (PSCs). Although the preferred growth along the (112) directions has been reported to promote charge transport within the Pb-based polycrystalline perovskite films, the preferred orientation growth of this facet is still difficult to be achieved due to the higher formation energy compared with the (110) plane. Herein, Sn-Pb binary perovskite films with a well-controlled orientation along the (224) plane were achieved by introducing a simple ultrasonic treatment (UST) into the additive engineering fabricated method.

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In the past few years, the power conversion efficiencies (PCEs) of perovskite solar cells (PSCs) have increased from 3.81 to 25.2%, surpassing those of all almost all thin films solar cells.

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In this work, the CuMnZnSn(S,Se) (0 ≤ ≤ 1) (CMZTSSe) alloy films were fabricated by a sol-gel method. Meanwhile, the effects of Mn substitution on the structural, morphological, electrical, optical, and device performance were studied systematically. The clear phase transformation from CuZnSn(S,Se) (CZTSSe) with kesterite structure to CuMnSn(S,Se) (CMTSSe) with stannite structure was observed as = 0.

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Cation substitution is a promising approach to reduce the antisite defects and further improve the efficiency of CuZnSn(S,Se) (CZTSSe) cells. In this paper, silver (Ag) has been introduced into CuZnSn(S,Se) (CZTSSe) thin film to replace Cu partially and form (CuAg)ZnSn(S,Se) (0 ≤ x ≤ 1) (CAZTSSe) alloy films by combination of solution method and a rapid annealing technique. The fundamental properties of the mixed Ag-Cu kesterite compound are systematically reported as a function of the Ag/(Ag+Cu) ratio.

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CuMgZnSnS (0 ≤ ≤0.6) thin films were prepared by a simple, low-temperature (300 °C) and low-cost sol-gel spin coating method followed by post-annealing at optimum conditions. We optimized the annealing conditions and investigated the effect of Mg content on the crystalline quality, electrical and optical performances of the CuMgZnSnS thin films.

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High-selenium CuMgZnSn(S,Se) (CMZTSSe) films were prepared on a soda lime glass substrate using the sol-gel spin coating method, followed by selenization treatment. In this work, we investigated the effects of selenization temperature and selenization time on the crystal quality, and electrical and optical properties of CMZTSSe films. The study on the micro-structure by XRD, Raman, X-ray photoelectron spectroscopy (XPS), and energy-dispersive X-ray spectroscopy (EDS) analysis showed that all CMZTSSe samples had kesterite crystalline structure.

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The breakthrough of organometal halide perovskite solar cells (PSCs) based on mesostructured composites is regarded as a viable member of next generation photovoltaics. In high efficiency PSCs, it is crucial to finely optimize the charge dynamics and optical properties matching between the perovskites and electron transporting materials to relax the trade-off between the optical and electrical requirements. Here, a simple antipolar route with HO as the additive is proposed to prepare hierarchical electron transporting layers to boost the efficiency of dopant-free PSCs.

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Chlorobenzene and diethyl ether were chosen as an antisolvent to control the crystallization of CHNHPbI. Under the condition of similar crystallization for both perovskite films, the obvious larger short-circuit current density for CHNHPbI film treated by chlorobenzene prompted us to unveil the roles of chlorobenzene in the perovskite films via adjusting the dropping amount of chlorobenzene. A novel insight of chlorobenzene function was revealed, that is, gradient diluted chlorine doping in the CHNHPbI film, which forms a gradient band gap in the perovskite films, prompts photogenerated carriers accumulating at the interface, makes the electron transport faster, and effectively enhances the power conversion efficiency (PCE) of solar cells.

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Metal-organic frameworks (MOFs), as drug delivery carriers, with high loading capacity and controllable release behavior can provide a more efficacious therapy in cancer treatments. In our work, a novel biocompatible zinc MOF Zn-cpon-1 with the (3,6)-connected rtl 3D topological network was designed and synthesized via employing ClO anion as template. The optically and chemically stable Zn-cpon-1 could be verified as a pH-responsive dual-emission platform and excellent drug delivery carrier with higher 5-fluorouracil (5-FU) (44.

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CuIn Zn SnS ( = 0.4) alloy thin films were synthesized on soda lime glass (SLG) substrate by a simple low-cost sol-gel method followed by a rapid annealing technique. The influence of sulfurization temperature and sulfurization time on the structure, morphology, optical and electrical properties of CuIn Zn SnS thin films was investigated in detail.

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We have investigated the role of hydrogen plasma pretreatment in promoting silicon surface passivation, in particular examining its effects on modifying the microstructure of the subsequently deposited thin hydrogenated amorphous silicon (a-Si:H) passivation film. We demonstrate that pretreating the silicon surface with hydrogen plasma for 40 s improves the homogeneity and compactness of the a-Si:H film by enhancing precursor diffusion and thus increasing the minority carrier lifetime (τ(eff)). However, excessive pretreatment also increases the density of dangling bond defects on the surface due to etching effects of the hydrogen plasma.

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In this study, hydrogenated amorphous silicon (a-Si:H) thin films are deposited using a radio-frequency plasma-enhanced chemical vapor deposition (RF-PECVD) system. The Si-H configuration of the a-Si:H/c-Si interface is regulated by optimizing the deposition temperature and post-annealing duration to improve the minority carrier lifetime (τeff) of a commercial Czochralski (Cz) silicon wafer. The mechanism of this improvement involves saturation of the microstructural defects with hydrogen evolved within the a-Si:H films due to the transformation from SiH2 into SiH during the annealing process.

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This paper evaluates the performance of the Coupled Model Intercomparison Project phase 5 (CMIP5) in simulating annual and decadal temperature in the Mekong River Basin from 1950 to 2005. By use of Bayesian multi-model averaging method, the future projection of temperature variation under different scenarios are also analyzed. The results show, the performances of climate model are more accurate in space than time, the model can catch the warming characteristics in the Mekong river Basin, but the accuracy of simulation is not good enough.

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