- 标题
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Lewis acid activated CO <sub/>2</sub> reduction over a Ni modified Ni–Ge hydroxide driven by visible-infrared light
摘要： Improvement of light harvesting and reaction kinetics is of great importance for achieving efficient solar-driven CO2 reduction. Here, a Ni modified low-crystalline Ni–Ge containing hydroxide with Lewis acid sites was synthesized in highly reductive NaBH4 solution and exhibited 9.3 μmol gcat.?1 h?1 CO and 3.5 μmol gcat.?1 h?1 CH4 generation rates under visible light irradiation, and even achieved a 3.8 μmol gcat.?1 h?1 CO evolution under infrared light irradiation. The wide-spectrum light harvesting resulted from the light absorption from the localized surface plasmonic resonance of Ni nanoparticles. In addition, the Lewis acid can activate CvO bonds to decrease the kinetic barriers of CO2 reduction. The design concept that rationally combines the advantages of expanding the spectral response and activating CO2 may offer a new strategy for efficient solar energy utilization.
关键词： visible-infrared light,plasmonic effect,Lewis acid,CO2 reduction,photocatalyst
更新于2025-11-19 16:51:07
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Characterizing Lewis Pairs Using Titration Coupled with In Situ Infrared Spectroscopy
摘要： Lewis acid-activation of carbonyl-containing substrates is a fundamental basis for facilitating transformations in organic chemistry. Historically, characterization of these interactions has been limited to models equivalent to stoichiometric reactions. Here, we report a method utilizing in situ infrared spectroscopy to probe the solution interactions between Lewis acids and carbonyls under synthetically relevant conditions. Using this method, we were able to identify 1:1 complexation between GaCl3 and acetone and a highly ligated complex for FeCl3 and acetone. The impact of this technique on mechanistic understanding is illustrated by application to the mechanism of Lewis acid-mediated carbonyl-olefin metathesis in which we were able to observe competitive binding interactions between substrate carbonyl and product carbonyl with the catalyst.
关键词： Lewis base,carbonyl,Lewis acid,infrared spectroscopy,titration,Issue 156,Chemistry,chemistry
更新于2025-09-19 17:13:59
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P3HT with Zn(C <sub/>6</sub> F <sub/>5</sub> ) <sub/>2</sub> as p‐Type Dopant for the Enhanced Performance of Planar Perovskite Solar Cells
摘要： The molecular organic Lewis acid bis(pentafluorophenyl)zinc [Zn(C6F5)2] is reported as an efficient p-type dopant for poly(3-hexylthiophene-2,5-diyl) (P3HT), to be used as hole-transporting material (HTM) in perovskite solar cells (PSCs) for the first time. To date, the most efficient PSCs use lithium bis(trifluoromethane) sulfonimide lithium salt (LiTFSI) and 4-tert-butylpyridine (tBP) as standard additives for HTMs. However, such dopants can induce deleterious effects on device stability. Herein, the effect of the concentration of Zn(C6F5)2 in P3HT HTM on the performance of PSCs is investigated. The P3HT-based PSCs using a low concentration of the dopant (0.025 mol%) in the HTM layer exhibit the best performance and the highest power conversion efficiency (PCE) of 17.49%, which is almost 3.5% higher than the achieved PCE for pristine P3HT-based PSCs. The origin of the improved performance for PSCs is further investigated, by studying the conductivity and hole mobility of the thin films based on pristine and doped P3HT. Adding a small amount of Zn(C6F5)2 to P3HT increases its thin-film hole mobility and its hole extraction ability.
关键词： Lewis acid dopants,poly(3-hexylthiophene-2,5-diyl),perovskite solar cells,hole-transporting materials
更新于2025-09-19 17:13:59
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Enhanced stability and solar cell performance via π-conjugated Lewis base passivation of organic inorganic lead halide perovskites
摘要： High power conversion efficiency (PCE) and good long-term stability of the perovskite solar cell (PSC) are two important factors on its commercial applications. Here, we propose a simple way to improve the PSC performance by adding 3,3',5,5'-azobenzene-tetracarboxylic acid (H4abtc) into the lead iodide (PbI2) precursor solution with Lewis acid-base adduct via two-step solution method. 24% enhancement of the PCE is achieved for the PSC with 2.0% H4abtc comparing with the pure PSC without H4abtc. Further research suggests that the H4abtc can passivate grain boundaries of perovskite film by reacting with the lead cation, therefore leading to good thermal stability and anti-moisture of perovskite films. The paper provides a new method to prepare a stable and efficient PSC by employing a novel Lewis base to passivate grain boundaries and gain high-quality perovskite films.
关键词： Perovskite solar cell,Additive,Two-step solution method,Lewis acid-base adduct
更新于2025-09-19 17:13:59
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[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Exciplex emission based on Lewis acid-base interaction
摘要： We exemplify a new exciplex emission system based on an appropriate electron donor (35DCzPPy) and a Lewis acid borane B(C6F5)3 acceptor. X-ray photoelectron spectroscopy proved that N-B bond formed between 35DCzPPy and B(C6F5)3, which make the charge transfer process more efficient. By the Lewis acid-base interaction, B(C6F5)3 has achieved blue-light emitting by the excited state intermolecular charge transfer process.
关键词： intermolecular charge transfer,Lewis acid-base interaction,Exciplex emission
更新于2025-09-16 10:30:52
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Efficient CsPbBr3 Inorganic Perovskite Light-Emitting Diodes via Lewis Acid-Base Reaction with Organic Small Molecule mCP
摘要： CsPbBr3 all-inorganic perovskite light-emitting diodes (PeLEDs) have received increasing attention in recent years due to their unique luminescent property and superior thermal stability. However, the low solubility of bromide precursors and the fast crystallization of perovskites usually cause the formation of discontinuous CsPbBr3 films with rough grains and large pin-holes. This would increase the defects and non-radiative recombination and severely degrade the device electroluminescence (EL) performance. To tackle this issue, herein, the 1,3-bis9H-carbazol-9-ylbenzene (mCP) small molecule was elaborately selected as an effective additive to enhance the film-forming ability of CsPbBr3 emissive layers. With the addition of mCP, the submicron-sized CsPbBr3 grains were reduced to nanometer range, and the resulting perovskite films became uniform and continuous. It was found that the electron pairs of N2- in mCP would donate to metal Pb2+ in CsPbBr3. Thus the so-called Lewis acid-base reaction occurred, which could retard the fast crystallization process and contribute to the connection of perovskite grains. As such, the film roughness was decreased from 8.28 nm to 1.62 nm, and the carrier lifetime was increased from 2.49 ns to 68.39 ns. The CsPbBr3:mCP device with an optimized mass ratio of 1:0.10 exhibited a maximum luminance (L) of 21008 cd/m2, a maximum current efficiency (CE) of 3.74 cd/A, and the corresponding maximum external quantum efficiency (EQE) of 1.21%, far surpassing the EL performance of the pristine CsPbBr3 PeLEDs.
关键词： Organic small molecule mCP,Effective additive,CsPbBr3 inorganic perovskite,Lewis acid-base reaction,Light-emitting diodes
更新于2025-09-16 10:30:52
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Additive Engineering for Efficient and Stable Perovskite Solar Cells
摘要： Perovskite solar cells (PSCs) have reached a certified 25.2% efficiency in 2019 due to their high absorption coefficient, high carrier mobility, long diffusion length, and tunable direct bandgap. However, due to the nature of solution processing and rapid crystal growth of perovskite thin films, a variety of defects can form as a result of the precursor compositions and processing conditions. The use of additives can affect perovskite crystallization and film formation, defect passivation in the bulk and/or at the surface, as well as influence the interface tuning of structure and energetics. Here, recent progress in additive engineering during perovskite film formation is discussed according to the following common categories: Lewis acid (e.g., metal cations, fullerene derivatives), Lewis base based on the donor type (e.g., O-donor, S-donor, and N-donor), ammonium salts, low-dimensional perovskites, and ionic liquid. Various additive-assisted strategies for interface optimization are then summarized; additives include modifiers to improve electron- and hole-transport layers as well as those to modify perovskite surface properties. Finally, an outlook is provided on research trends with respect to additive engineering in PSC development.
关键词： perovskite solar cells,additives,stability,Lewis acid,defect passivation
更新于2025-09-11 14:15:04
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Dual Catalytic Switchable Divergent Synthesis: An Asymmetric Visible-light Photocatalytic Approach to Fluorine-containing γ-Keto Acid Frameworks
摘要： Herein, we describe a novel and efficient method for constructing a series of fluorine-containing γ-keto acid derivatives through combining visible-light photoredox catalysis and chiral Lewis acid catalysis. With this dual catalytic strategy, a variety of chiral γ-keto amides containing a gem-difluoroalkyl group and a series of fluorine-containing α,β-unsaturated-γ-keto esters were successfully constructed with high stereoselectivities, respectively. A series of experiments showed that the chemoselectivity of this process was highly dependent on the fluorine reagents besides the Lewis acid catalysts. This approach facilitates rapid access to γ-keto acid derivatives, an important class of precursors for pharmaceuticals, plasticizers, and various other additives.
关键词： γ-keto acid derivatives,chiral Lewis acid catalysis,visible-light photocatalysis,asymmetric difluoroalkylation
更新于2025-09-10 09:29:36
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Lewis-Acid-Catalyzed BODIPY Boron Functionalization Using Trimethylsilyl Nucleophiles
摘要： A novel and straightforward strategy for boron functionalization in boron dipyrromethenes (BODIPYs) is developed. In particular, this synthetic strategy provides new possibilities for the synthesis of sp2 N-substituted (B-NCS and -NCO), benzotriazole- and trifluoroacetamide-substituted BODIPYs that were hitherto unknown. These new BODIPYs display an array of highly desirable photophysical properties (0.04 < Φ f < 0.86), paving the road for further investigations in material applications.
关键词： photophysical properties,boron functionalization,trimethylsilyl nucleophiles,Lewis acid catalysis,BODIPY
更新于2025-09-09 09:28:46