查找使用阿拉丁产品的科研文献

Significant roles of surface functional groups and Fe/Co redox reactions on peroxymonosulfate activation by hydrochar-supported cobalt ferrite for simultaneous degradation of monochlorobenzene and p-chloroaniline

Lei Yang,Zifei Wei,Zihan Guo,Mengfang Chen,Jingchun Yan,Linbo Qian,Lu Han,Jing Li,Mingyue Gu

CoFe 2 O 4 /hydrochar composites (FeCo@HC) were synthesized via a facile one-step hydrothermal method and utilized to activate peroxymonosulfate (PMS) for simultaneous degradation of monochlorobenzene (MCB) and p-chloroaniline (PCA). Additionally, the effects of humic acid , Cl - , HCO 3 - , H 2 PO 4 -, HPO 4 2- and water matrices were investigated and degradation pathways of MCB and PCA were proposed. The removal efficiencies of MCB and PCA were higher in FeCo@HC140–10/PMS system obtained under hydrothermal temperature of 140 °C than FeCo@HC180–10/PMS and FeCo@HC220–10/PMS systems obtained under higher temperatures. Radical species (i.e., SO 4 • - , •OH) and nonradical pathways (i.e., 1 O 2 , Fe (IV)/Co (IV) and electron transfer through surface FeCo@HC140–10/PMS* complex) co-occurred in the FeCo@HC140–10/PMS system, while radical and nonradical pathways were dominant in degrading MCB and PCA respectively. The surface functional groups (i.e., C-OH and C O) and Fe/Co redox cycles played crucial roles in the PMS activation . MCB degradation was significantly inhibited in the mixed MCB/PCA solution over that in the single MCB solution, whereas PCA degradation was slightly promoted in the mixed MCB/PCA solution. These findings are significant for the provision of a low-cost and environmentally-benign synthesis of bimetal-hydrochar composites and more detailed understanding of the related mechanisms on PMS activation for simultaneous removal of the mixed contaminants in groundwater.

Natural Product Additive with Multifunctional Groups Enhancing the Efficiency and Stability of Perovskite Solar Cells

Yonglei Han,Chao Zhou,Shuchen Weng,Guicheng Yu,Fang Lin,Hanlin Hu,Yongfei Wang,Haoran Lin

Perovskite solar cells (PSCs) are widely studied as the most promising photovoltaic technology, but their performance is sensitive to the morphology and the defect density of the perovskite films. Herein, additive engineering strategy is applied to further improve the film morphology and device performance by doping a small amount of natural product, D-Aspartic acid (D-2-Aminobutanedioic acid, D-Asp), into perovskite precursor solution. The modified device exhibits a greatly enhanced power conversion efficiency of 22.7%, which is unprecedented for PSCs doped with natural amino acids, and 3000 h stability in ambient air is achieved. Through systematical characterizations, it is concluded that D-Asp could result in thicker film formation, outstanding perovskite film morphology, and reduced defect sites passivated by the multiple functional groups. The results prove that the performance and stability of the state-of-the-art mixed ion PSCs with regular architecture could be effectively enhanced by D-Asp. The minimum usage of the natural product as an additive is beneficial for the fabrication process and cost-control in the industrialization of PSCs. This work also highlights the different passivating mechanisms for the molecules with multiple functional groups which are meaningful for materials design.

Interfacial engineering by p-methylphenylmethylammonium iodide for efficient carbon counter electrode (CE)-based 2D/3D hybrid perovskite solar cells

Duoling Cao,Zuhong Li,Ya Xu,Wenbo Li,Hang Zhong,Yin Huang,Xu Zhang,Li Wan,Xiuhua Zhang,Yuebin Li,Xiaoming Ren,Xianbao Wang,Dominik Eder,Shimin Wang

Defects at the surface and grain boundaries of three-dimensional (3D) organic-inorganic metal halide perovskite films lead to the non-radiative recombination of charge carriers and accelerate perovskite decomposition. In turn, this deteriorates the power conversion efficiency ( PCE ) and stability of perovskite solar cells (PSCs). Herein, p -methylphenylmethylammonium iodide ( p -MePMAI) was reacted with a 3D perovskite to in - situ form a two-dimensional (2D) perovskite upper layer. This upper layer passivated the surface and grain boundary defects of the 3D perovskite film, improving its surface hydrophobicity . As a result, a carbon counter electrode (CE)-based 2D/3D PSC achieved a maximum PCE of up to 15.63%, which was much higher than that of an unmodified 3D MAPbI 3 PSC (12.16%). Moreover, the unencapsulated 2D/3D device maintained 80% of its initial PCE after exposure to air for 700 h with a relative humidity (RH) of 40 ± 5%. This research opens a new pathway for the successful construction of stable and efficient 2D/3D PSCs with organic ammonium salts .

Design of Prussian Blue Analogue-Derived Magnetic Binary Ce–Fe Oxide Catalysts for the Selective Oxidation of Cyclohexane

Shuang Wei,Hao Li,Kexin Li,Ruirui Zhang,Guosheng Wang,Ruixia Liu

We report the fabrication of Ce–Fe oxides (CFOs) derived from Prussian blue analogues (PBAs) with different shapes of sphere (CFO-S), bipyramid (CFO-B), and flower (CFO-F), which are prepared by controlling the volume ratio of water and ethanol and the addition of deep eutectic solvents (DESs) to control the solvent environment using a modified coprecipitation method. The structure, morphology, and the surface properties of Ce–Fe oxides were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). The catalytic performance of PBA-derived Ce–Fe oxides was evaluated for the oxidation of cyclohexane, which positively correlated with surface oxygen vacancy and the amount ratio of Ce/Fe. The conversion for cyclohexane of CFO-S and CFO-B was 9.03 and 9.25%, respectively. However, CFO-S had a higher selectivity for K/A-oil (cyclohexanone and cyclohexanol) of 81.8%, resulting from the exposed crystal plane (100) compared to CFO-B (75%). Besides, CFO-F was rich in the Fe2O3 crystal phase, which is beneficial for KA selectivity. It was found that Ce3+, Fe3+, and OV had an important influence on the activation of C–H bonds, which provides a reference for the design of efficient alkane oxidation catalysts.

Simple Molecules as Hole Transport Materials Enabled by Solvothermal Technology: Towards Solution-Processable Carbon Electrode Perovskite Solar Cells

Yuntao He,Xin Ke,Wenying Shi

Incorporating formamidinium into 4-fluoro-phenethylammonium based quasi-2D perovskite films and their application in n-i-p perovskite solar cells

Shun Lu,Kegui Li,Ruojing Zhen,Maling Xiang,Xiaoyan Gan,Liling Guo,Hanxing Liu

Recently, perovskite solar cells (PSCs) basing on quasi-two-dimensional (quasi-2D) perovskites with hydrophobic bulky organic cations have received a lot of interests owing to their superior moisture stability. While quasi-2D perovskites have achieved great success in planar p-i-n PSCs, their application in planar n-i-p devices and the corresponding efficiencies lag far behind. In our work, (FPEA) 2 (MA) 4 Pb 5 I 16 perovskite films with high crystallinity , compact and smooth surface were deposited on electron transport layer with NH 4 SCN as an additive. Formamidinium (FA + ) were then incorporated into the FPEA based perovskite films to partially replace methylammonium (MA + ), and effects of FA + on the film's vertical orientation, light absorption capacity, carrier lifetime, defect density and electron mobility were studied. It was found that when molar ratio of FA/MA = 0.5/9.5, the film had the highest vertical orientation, enhanced light absorption, less carrier recombination loss. The obtained (FPEA) 2 (FA 0.05 MA 0.95 ) 4 Pb 5 I 16 based n-i-p PSCs gave a maximum efficiency of 12.17% under standard illumination, retaining 83% of the initial efficiency after stored in air environment (25–30 °C) with 40 ± 5% RH for 1080 h. The results demonstrate an efficient approach to prepare high-quality quasi-2D perovskite films in a n-i-p structure as well as improved device efficiency and stability.

Optimization of perovskite/carbon interface performance using N-doped coal-based graphene quantum dots and its mechanism analysis

Qixu Hu,Xiaoyu Yang,Ying Qi,Peng Wei,Jian Cheng,Yahong Xie

Optimizing the interfacial properties between perovskite and carbon electrodes has always been an important way to improve the photoelectric conversion efficiency (PCE) of carbon-based perovskite solar cells (C-PSCs) and facilitate their commercialization. In this paper, nitrogen-doped graphene quantum dots (N-GQDs) with fluorescent properties were successfully prepared using inexpensive coal as raw material by a facile and environmentally friendly chemical reagent oxidation. The results show that the electron-rich pyridinic nitrogen in N-GQDs can act as Lewis bases to form coordination bonds with uncoordinated lead ions by sharing electron pairs, thereby reducing the defect density and nonradiative recombination of photo-generated electron-hole, and extending lifetime of charge carriers. In addition, due to the passivation of N-GQDs, the hysteresis effect of the device is significantly reduced and the long-term stability is also improved. By optimizing the concentration, the PCE of C-PSCs achieved a maximum of 14.31%, which was improved by 20.25% compared with 11.90% of the pristine C-PSCs. This work provides a facile, environmentally friendly and efficient strategy for improving the overall performance of C-PSCs using inexpensive coal-based N-GQDs.

Synergistic effect between Co single atoms and nanoparticles enables selective synthesis of bio-based benzimidazoles

Baoyu Wang,Mingrui Li,Songdang Zhang,Hongguo Wu,Yuhe Liao,Hu Li

Finite size effect is closely correlated with heterogeneous catalytic activity and selectivity as reducing the metal to a few nanometers, but may suffer from deficient active sites for cascade reactions. Here, a type of dual-size heterogeneous N-doped cobalt catalysts (Co SAs-NPs /NC(n)) with the coexistence of Co single-atoms (Co-SAs) and Co nanoparticles (Co-NPs) were prepared for efficient synthesis of benzimidazoles (up to 91% yield) from 2-nitroanilines and bio-based alcohols via cascade hydrogen transfer-dehydrogenative cyclization. Experimental results and density functional theory calculations suggested that the bio-alcohol dehydrogenation mainly occurs at Co-SAs sites, while Co-NPs sites remarkably facilitate the subsequent reduction of nitro species, indicating the synergistic effect between Co-SAs and Co-NPs in the coupled hydrogen transfer process. The Co SAs-NPs /NC(0.25) catalyst can be recycled and applied to a wide range of substrates (28 examples). This catalytic approach based on the metal size effect opens a new route for the direct upgrading of biomass feedstocks involving multiple reactions.

Molecularly understanding and regulating carrier injection behavior of ETL/perovskite towards high performance PeLEDs

Qungui Wang,Keli Wang,Cheng Yan,Xiankan Zeng,Xuehai Fu,Jingjing Cao,Shiyu Yang,Wen Li,Xiangrong Chen,Weiqing Yang

Effectively balancing carrier injection of perovskite LEDs (PeLEDs) for next-generation display and illumination urgently needs for molecularly understanding carrier injection behavior of electron transport layer (ETL)/perovskite toward further developing high performance PeLEDs. Here, we molecularly reveal the electron injection behaviors of PeLEDs by theoretically-experimentally decoupling the electron transport of ETLs and electron injection of TmPyPB/perovskite and TPBi/perovskite. Resulted, the better molecular planarity bridging effect (MPBE) of TmPyPB than TPBi can effectively increase electronic-coupling for the improved electron transport ability and significantly decrease injection barrier for the enhanced electron injection capability, intrinsically leading to a more balanced carrier injection and a less electron accumulation of PeLEDs. Compared to TPBi-based PeLEDs, the TmPyPB-based PeLEDs present the obviously-increased average EQE, current efficiency, power efficiency and luminance by 44 %, 63 %, 43 % and 100 %, respectively. Meanwhile, this PeLED shows a higher voltage tolerance characteristic of 7.5 V than that of TPBi-based PeLEDs (6.25 V). Therefore, this work may provide a fundamental insight into carrier injection behavior of PeLEDs for effectively-regulating its carrier injection balance and further for its greatly-facilitated commercialization.

A multifunctional strategy of two-dimensional WS2 modified absorbers for efficient planar perovskite solar cells

Qinghua Sun,Wanting Hu,Miao Yu,Fengyou Wang,Xiaoyan Liu,Lihua Yang,Huilian Liu,Lin Fan,Lili Yang

The development of functional absorbers with excellent film-forming quality and carrier extraction/transfer efficiency is of great significance to achieve high-efficiency and stable n–i–p planar perovskite solar cells (PSCs). Herein, we propose a simple in situ growth technique to construct high-quality absorbers by introducing a commercial two-dimensional (2D) tungsten sulfide nanosheet (WS2 NS) modifier during the growth of a perovskite. The synergistic effects of WS2 on perovskite crystallization kinetics, charge extraction/transfer/recombination behaviors, and device photovoltaic outputs were systematically studied. Owing to the strong coordination effect between WS2 NSs and organic cations in a perovskite, WS2 can be used as a growth template in the crystallization process of the perovskite, thus effectively passivating grain boundaries and surface/interface trap states, and synchronously improving the film-forming quality, surface/interface contact, and photogenerated charge extraction/transfer efficiency of the perovskite. Moreover, WS2 located at the grain boundaries and surface/interface provides the “fast paths” for photogenerated electron–hole pairs by virtue of its high charge mobility, which greatly inhibits the accumulation/recombination of charge carriers and effectively improves the photovoltaic performance and hysteresis behavior of planar PSCs. Additionally, WS2 NSs induce the substitutional doping of formamidinium cations, which has a positive contribution to broadening the spectral response range. The results show that the efficiency of the WS2-modified PSC is significantly better than that of the conventional planar device. The non-encapsulated functionalized devices also exhibit good stability due to the multifunctional effects of a WS2-modified perovskite, resulting in great advantages for the development of highly efficient flexible-, semitransparent-, and tandem-photovoltaic applications.

ZnPc/CsPbBr3 QDs collaborative interface modification to improve the performance of CsPbBr3 perovskite solar cells

Li Zou,Xiaoyan Li,Meili Yang,Jiahao Yan,Jiaming Wang,Jiajie Cheng,Jie Xing,Hao Liu,Huiying Hao,Jingjing Dong

Carbon-based, all-inorganic CsPbBr 3 perovskite solar cells (PSCs) have attracted considerable interests because of their superior environmental stability, simple and low-cost fabrication process. However, the large energy barrier and high defect states at the CsPbBr 3 /Carbon interface will cause poor carrier extraction and serious carrier recombination, which further degrade performance of final devices. In this work, we introduce zinc phthalocyanine (ZnPc), CsPbBr 3 quantum dots (QDs), and ZnPc mixed CsPbBr 3 QDs in proper proportion as the CsPbBr 3 /carbon interface modification layers of CsPbBr 3 PSCs. It is found that the modification layers, especially the ZnPc mixed CsPbBr 3 QDs modification layer, can passivate trap states, improve interface contact and optimize energy level alignment at the CsPbBr 3 /carbon interface, which can further enhance carrier extraction, suppress carrier recombination and improve performance of final devices. By virtue of ZnPc mixed CsPbBr 3 QDs modification, a highest efficiency of 10.20% and long-term stability over 6 months has been achieved.

Cs1−xDMAxPbI3 versus CsPbI3 for Perovskite Solar Cells

Mengqi Liu,Linrui Duan,T. Jesper Jacobsson,Jingshan Luo

Inorganic CsPbI 3 perovskite solar cells (CsPbI 3 PSCs) have attracted extensive attention because of their excellent thermal stability and appropriate bandgap for tandem solar cells. At present, intermediate phase engineering with organic additive, e.g., dimethyl amine iodide (DMAI), is the most common method to obtain high-efficiency CsPbI 3 PSCs. However, it remains controversial whether the intermediate phase is entirely converted into a pure CsPbI 3 phase. By exploring the effect of annealing temperature, herein, it is demonstrated that substantial organic residues remain in the produced films while using the current standard recipes of DMA + -assisted synthesis of Cs 1− x DMA x PbI 3 perovskites. Thermal gravimetric and nuclear magnetic resonance show that DMA + remains in films annealed at a standard annealing temperature of 190 °C. The DMA + does, however, disappear if the annealing temperature is increased to 340 °C, which leads to a larger grain size, a contraction of the lattice, a narrower bandgap, and a redshift of the absorption onset. Though both Cs 1− x DMA x PbI 3 and CsPbI 3 perovskite solar cells show decent efficiencies, the pure CsPbI 3 perovskite solar cells annealed at a higher temperature demonstrate higher operational stability.