Quaternized chitosan-based organic-inorganic nanohybrid nanoparticles loaded with prothioconazole for efficient management of fungal diseases with minimal environmental impact.

Poor foliar deposition and retention of pesticides results in serious pesticide residues and environmental pollution. Organic-inorganic hybridized nanoparticles (OIHN), combining the advantages of organic and inorganic materials, can be used as carriers to load pesticides for efficient and safe application. Herein, a novel multifunctional OIHN composed of mesoporous silica nanoparticles (MSNs) and cationic chitosan quaternary ammonium salt (HACC) was constructed and used as a delivery system for prothioconazole (PTC). The resultant PTC@MSNs-HACC exhibited a remarkable loading capacity of 39.07 wt% and demonstrated enhanced PTC release (31.47 %) under alkaline conditions. The UV-shielding properties of MSNs efficiently shielded PTC from photodegradation, increasing its photostability by over threefold. The strong positive charge of HACC conferred excellent adhesion of PTC@MSNs-HACC to fungal cell membranes, leading to high deposition on wheat leaves with improved rain-wash resistance (increased by 30 %). Consequently, PTC@MSNs-HACC (EC50: 12.48 mg/L) exhibited superior wheat scab control compared to PTC emulsifiable concentrate (EC50: 28.49 mg/L). Additionally, PTC@MSNs-HACC displayed excellent uptake and transport in plants, ensuring plant safety and reducing toxicity to zebrafish by >1-fold. The potential application of the developed PTC@MSNs-HACC in agricultural production holds significant promise and is anticipated to find widespread use in the future.

Defect Compensation and Lattice Stabilization Enables High Voltage Output in Tin Halide Perovskite Solar Cells.

Tin halide perovskite solar cells (PSCs) are regarded as the most promising lead-free alternatives for photovoltaic applications. However, they still suffer from uncompetitive photovoltaic performance because of the facile Sn2+ oxidation and Sn-related defects. Herein, a defect and carrier management strategy by using diaminopyridine (DP) and 4-bromo-2,6-diaminopyridine (4BrDP) as multifunctional additives for tin halide perovskites is reported. Both DP and 4BrDP induced strong interaction with tin perovskites by coordinate bonding and N─H···I hydrogen bonding, which greatly suppresses the micro-strain and Urbach energy of tin halide perovskite films. The strong hydrogen bonding inhibits the formation of I3 - and related defect density. Meanwhile, the electron-donor species of halogen bond in 4BrDP provides higher reactivity of 2 and 6 sites, which indicates stronger passivation ability with tin halide perovskites. These advances enable a champion power conversion efficiency (PCE) of 13.40% in 4BrDP-processed devices with remarkable improvement in both open-circuit voltage (Voc) of 881 mV and fill factor (FF) of 71.26%. The 4BrDP devices retain 91% and 82% of the pristine PCE after 2000 h storage in N2 atmosphere and 1000 h under 85 °C, respectively. Therefore, this work provides new insight into molecular design for high-performance and stable lead-free optoelectronics.

An efficient method for improving the stability of Monascus pigments using ionic gelation.

BACKGROUND: Monascus pigments (Mps) are easily impacted by heating, pH and light, resulting in degradation. In this study, Mps were encapsulated by the ionic gelation method with sodium alginate (SA) and sodium caseinate (SC), as well as CaCl2 as a crosslinker. The encapsulated Mps SA/SC in four proportions (SA/SC: 1/4, 2/3, 3/2, 4/1, w/w). Then, the encapsulation efficiency and particle size of the SA/SC-Mps system were evaluated to obtain the optimal embedding conditions. Finally, the effects of heating, pH, light and storage on the stability of non-capsulated Mps and encapsulated Mps were assessed. RESULTS: SA/SC = 2/3 (AC2) had higher encapsulation efficiency (74.30%) of Mps and relatively small particle size (2.02 mm). The AC2 gel beads were chosen for further investigating the stability of encapsulated Mps to heating, pH, light and storage. Heat stability experiments showed that the degradation of Mps followed first-order kinetics, and the encapsulated Mps had lower degradation rates than non-capsulated Mps. Encapsulation could reduce the effect of pH on Mps. The effects of ultraviolet light on the stability of Mps were considered, and showed that the retention efficiency of encapsulated Mps was 22.01% higher than that of non-capsulated Mps on the seventh day. Finally, storage stability was also evaluated under dark refrigerated conditions for 30 days, and the results indicated that encapsulation could reduce the degradation of Mps. CONCLUSION: This study has proved that AC2 gel beads can improve the stability of Mps. Thus, the ionic gelation method is a promising encapsulation method to improve the stability of Mps. © 2023 Society of Chemical Industry.

Tuning the phase separation of PEDOT:PSS affords efficient lead-free perovskite solar cells.

Poly(3,4-ethylenedioxythiphene):poly(styrenesulfonate) (PEDOT:PSS) shows great potential for applications in tin halide perovskite solar cells (TPSCs). Nevertheless, the physicochemical, electrical properties and surface characteristics of pristine PEDOT:PSS are poorly suitable for high-quality tin halide perovskite films, as well as for efficient carrier transport. In this work, we tuned the phase separation of PEDOT and PSS chains by ammonium carbamate (AC). The modified film showed a lower trap density and more facile carrier transport than did the pristine film. Consequently, the target TPSCs achieved a substantially improved short-circuit photocurrent (Jsc) and open-circuit voltage (Voc), together with a markedly improved power conversion efficiency (PCE) from 9.48% to 11.24%.

Novel PHA Organic Spacer Increases Interlayer Interactions for High Efficiency in 2D Ruddlesden-Popper CsPbI3 Solar Cells.

The two-dimensional (2D) Ruddlesden-Popper (RP) CsPbI3 with hydrophobic organic spacers can significantly improve the environmental and phase stability of photovoltaic devices by suppressing ion migration and inducing steric hindrance. However, due to the multiple-quantum-well structure, these spacer cations lead to weak interactions in 2D RP CsPbI3, which seriously affect the carrier transport. Here, a novel N-H-group-rich phenylhydrazine spacer, namely, PHA, was developed for 2D RP CsPbI3 perovskite solar cells (PSCs). A series of characterizations confirm that the 2D perovskites using PHA spacers enhanced the N-H···I hydrogen-bonding interaction between the organic spacer cations and the [PbI6]4- inorganic layer and accelerated the crystallization rate of the perovskite film, which was beneficial to the preparation of high-quality films with preferred vertical orientation, large grain size, and dense morphology. Meanwhile, the trap state density of the as-prepared 2D RP perovskite films is significantly reduced to enable efficient charge carrier transport. As a result, the (PHA)2Cs4Pb5I16 PSCs achieved a performance of 16.23% with good environmental stability. This work provides a simple organic spacer selection scheme to realize interaction optimization in 2D RP CsPbI3 to develop efficient and stable PSCs.

Ordered Element Distributed C3 N Quantum Dots Manipulated Crystallization Kinetics for 2D CsPbI3 Solar Cells with Ultra-High Performance.

Two-dimensional (2D) CsPbI3 is developed to conquer the phase-stability problem of CsPbI3 by introducing bulky organic cations to produce a steric hindrance effect. However, organic cations also inevitably increase the formation energy and difficulty in crystallization kinetics regulation. Such poor crystallization process modulation of 2D CsPbI3 leads to disordered phase-arrangement, which impedes the transport of photo-generated carriers and worsens device performance. Herein, a type of C3 N quantum dots (QDs) with ordered carbon and nitrogen atoms to manipulate the crystallization process of 2D CsPbI3 for improving the crystallization pathway, phase-arrangement and morphology, is introduced. Combination analyses of theoretical simulation, morphology regulation and femtosecond transient absorption (fs-TA) characterization, show that the C3 N QDs induce the formation of electron-rich regions to adsorb bulky organic cations and provide nucleation sites to realize a bi-directional crystallization process. Meanwhile, the quality of 2D CsPbI3 film is improved with lower trap density, higher surface potential, and compact morphology. As a result, the power conversion efficiency (PCE) of the optimized device (n = 5) boosts to an ultra-high value of 15.63% with strengthened environmental stability. Moreover, the simple C3 N QDs insertion method shows good universality to other bulky organic cations of Ruddlesden-Popper and Dion-Jacobson, providing a good modulation strategy for other optoelectronic devices.

Strategies for Improving the Stability of Tin-Based Perovskite (ASnX3) Solar Cells.

Although lead-based perovskite solar cells (PSCs) are highly efficient, the toxicity of lead (Pb) limits its large-scale commercialization. As such, there is an urgent need to find alternatives. Many studies have examined tin-based PSCs. However, pure tin-based perovskites are easily oxidized in the air or just in glovebox with an ultrasmall amount of oxygen. Such a characteristic makes their performance and stability less ideal compared with those of lead-based perovskites. Herein, how to address the instability of tin-based perovskites is introduced in detail. First, the crystalline structure, optical properties, and sources of instability of tin-based perovskites are summarized. Next, the preparation methods of tin-based perovskite are discussed. Then, various measures for solving the instability problem are explained using four strategies: additive engineering, deoxidizer, partial substitution, and reduced dimensions. Finally, the challenges and prospects are laid out to help researchers develop highly efficient and stable tin-based perovskites in the future.

Imidazolium Ionic Liquid Modified Graphene Oxide: As a Reinforcing Filler and Catalyst in Epoxy Resin.

Surface modification of graphene oxide (GO) is one of the most important issues to produce high performance GO/epoxy composites. In this paper, the imidazole ionic liquid (IMD-Si) was introduced onto the surface of GO sheets by a cheap and simple method, to prepare a reinforcing filler, as well as a catalyst in epoxy resin. The interlayer spacing of GO sheets was obviously increased by the intercalation of IMD-Si, which strongly facilitated the dispersibility of graphene oxide in organic solvents and epoxy matrix. The addition of 0.4 wt % imidazolium ionic liquid modified graphene oxide (IMD-Si@GO), yielded a 12% increase in flexural strength (141.3 MPa), a 26% increase in flexural modulus (4.69 GPa), and a 52% increase in impact strength (18.7 kJ/m²), compared to the neat epoxy. Additionally the IMD-Si@GO sheets could catalyze the curing reaction of epoxy resin-anhydride system significantly. Moreover, the improved thermal conductivities and thermal stabilities of epoxy composites filled with IMD-Si@GO were also demonstrated.

Microwave-assisted method for simultaneous extraction and hydrolysis for determination of flavonol glycosides in Ginkgo foliage using Brönsted acidic ionic-liquid [HO(3)S(CH(2))(4)mim]HSO(4) aqueous solutions.

The Brönsted acidic ionic-liquid [HO(3)S(CH(2))(4)mim] HSO(4), a novel dual catalyst-solvent, has been successfully applied in simultaneous microwave-assisted extraction and hydrolysis for the determination of flavonol glycosides in Ginkgo foliage. The parameters, namely the [HO(3)S(CH(2))(4)mim]HSO(4) concentration, microwave-irradiation power, microwave-irradiation time, and solid-liquid ratio, were optimized. The optimum conditions were: an amount of 1.5 M [HO(3)S(CH(2))(4)mim]HSO(4), a microwave-irradiation power of 120 W, an irradiation time of 15 min, and a solid-liquid ratio of 1:30 g/mL. Compared with traditional methods the proposed approach demonstrates higher efficiency in a shorter operating time, and is an efficient, rapid, and simple sample preparation method.