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1.
ACS Nano ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627232

RESUMO

Hydro-depolymerization presents a promising avenue for transforming plastic waste into high-value hydrocarbons, offering significant potential for value-added recycling. However, a major challenge in this method arises from kinetic limitations due to insufficient hydrogen concentration near the active sites, requiring optimal catalytic performance only at higher hydrogen pressures. In this study, we address this hurdle by developing "hydrogen bubble catalysts" featuring Ru nanoparticles within mesoporous SBA-15 channels (Ru/SBA). The distinctive feature of Ru/SBA catalysts lies in their capacity for physical hydrogen storage and chemically reversible hydrogen spillover, ensuring a timely and ample hydrogen supply. Under identical reaction conditions, the catalytic activity of Ru/SBA surpassed that of Ru/SiO2 (no hydrogen storage capacity) by over 4-fold. This substantial enhancement in catalytic performance provides significant opportunities for near atmospheric pressure hydro-depolymerization of plastic waste.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38636167

RESUMO

The interest in introducing light into heterogeneous catalysis is driven not only by the urgent need of replacing fossil energy but also by the promise of controlling product selectivity by light. The product selectivity differences observed in recent studies between light and dark reactions are often attributed to photochemical effects. Here, we report the discovery of a non-photochemical origin of selectivity difference, at essentially the same CO2 conversion rate, between photothermal and thermal CO2 hydrogenation reactions over a Ru/TiO2-x catalyst. While the presence of the photochemical effect from ultraviolet light is confirmed, it merely enhances the catalytic activity. Systematic investigation reveals that the gradual formation of an adsorbate-mediated strong metal-support interaction under catalytic conditions is responsible for the variation in the catalytic selectivity. We demonstrate that differences in product selectivity under light/dark reactions do not necessarily originate from photochemical effects. Our study refines the basis for determining photochemical effects and highlights the importance of excluding non-photochemical effects in mechanistic studies of light-controlled product selectivity.

3.
J Am Chem Soc ; 146(15): 10655-10665, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38564662

RESUMO

While Ru-catalyzed hydrogenolysis holds significant promise in converting waste polyolefins into value-added alkane fuels, a major constraint is the high cost of noble metal catalysts. In this work, we propose, for the first time, that Co-based catalysts derived from CoAl-layered double hydroxide (LDH) are alternatives for efficient polyolefin hydrogenolysis. Leveraging the chemical flexibility of the LDH platform, we reveal that metallic Co species serve as highly efficient active sites for polyolefin hydrogenolysis. Furthermore, we introduced Ni into the Co framework to tackle the issue of restricted hydrogenation ability associated with contiguous Co-Co sites. In-situ analysis indicates that the integration of Ni induces electron transfer and facilitates hydrogen spillover. This dual effect synergistically enhances the hydrogenation/desorption of olefin intermediates, resulting in a significant reduction in the yield of low-value CH4 from 27.1 to 12.6%. Through leveraging the unique properties of LDH, we have developed efficient and cost-effective catalysts for the sustainable recycling and valorization of waste polyolefin materials.

4.
J Am Chem Soc ; 146(10): 7076-7087, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38428949

RESUMO

The present polyolefin hydrogenolysis recycling cases acknowledge that zerovalent Ru exhibits high catalytic activity. A pivotal rationale behind this assertion lies in the propensity of the majority of Ru species to undergo reduction to zerovalent Ru within the hydrogenolysis milieu. Nonetheless, the suitability of zerovalent Ru as an optimal structural configuration for accommodating multiple elementary reactions remains ambiguous. Here, we have constructed stable Ru0-Ruδ+ complex species, even under reaction conditions, through surface ligand engineering of commercially available Ru/C catalysts. Our findings unequivocally demonstrate that surface-ligated Ru species can be stabilized in the form of a Ruδ+ state, which, in turn, engenders a perturbation of the σ bond electron distribution within the polyolefin carbon chain, ultimately boosting the rate-determining step of C-C scission. The optimized catalysts reach a solid conversion rate of 609 g·gRu-1·h-1 for polyethylene. This achievement represents a 4.18-fold enhancement relative to the pristine Ru/C catalyst while concurrently preserving a remarkable 94% selectivity toward valued liquid alkanes. Of utmost significance, this surface ligand engineering can be extended to the gentle mixing of catalysts in ligand solution at room temperature, thus rendering it amenable for swift integration into industrial processes involving polyolefin degradation.

5.
J Phys Chem Lett ; 15(12): 3441-3449, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38511538

RESUMO

The vulnerability of mixed halide perovskite nanocrystals (NCs) remains challenging because of the weak interaction between commonly employed ligands, oleic acid/oleylamine (OAm/OA) and halide anions, coupled with substantial surface phonon energy. Here, we introduce 3-aminopropyltriethoxysilane (APTES) as a capping ligand to modify CsPbBrI2 NCs to enhance the interactions between them. The optical properties have been significantly enhanced, and halide segregation has been suppressed, both of which can be attributed to the reduced phonon energy and exciton-phonon coupling strength. Moreover, these APTES-CsPbBrI2 NCs exhibit a broad color gamut and sustained color stability during long-term operation, indicating their promising potential in display technologies. This work may offer insights into surface engineering to enhance the properties and band stability of mixed halide perovskite NCs.

6.
Nat Commun ; 15(1): 2730, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548730

RESUMO

Lithium-ion batteries (LIBs) and plastics are pivotal components of modern society; nevertheless, their escalating production poses formidable challenges to resource sustainability and ecosystem integrity. Here, we showcase the transformation of spent lithium cobalt oxide (LCO) cathodes into photothermal catalysts capable of catalyzing the upcycling of diverse waste polyesters into high-value monomers. The distinctive Li deficiency in spent LCO induces a contraction in the Co-O6 unit cell, boosting the monomer yield exceeding that of pristine LCO by a factor of 10.24. A comprehensive life-cycle assessment underscores the economic viability of utilizing spent LCO as a photothermal catalyst, yielding returns of 129.6 $·kgLCO-1, surpassing traditional battery recycling returns (13-17 $·kgLCO-1). Solar-driven recycling 100,000 tons of PET can reduce 3.459 × 1011 kJ of electric energy and decrease 38,716 tons of greenhouse gas emissions. This work unveils a sustainable solution for the management of spent LIBs and plastics.

7.
Chem Commun (Camb) ; 60(21): 2828-2838, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38362916

RESUMO

Plastic waste in the environment causes significant environmental pollution. The potential of using chemical methods for upcycling plastic waste offers a dual solution to ensure resource sustainability and environmental restoration. This article provides a comprehensive overview of the latest technologies driven by solar-driven, electro/photoelectrochemical-catalytic, and microwave-assisted methods for the conversion of plastics into various valuable chemicals. It emphasizes selective conversion during the plastic transformation process, elucidates reaction pathways, and optimizes product selectivity. Finally, the article offers insights into the future developments of chemical upcycling of polyesters.

8.
Angew Chem Int Ed Engl ; 63(3): e202316154, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38058217

RESUMO

Additive engineering has emerged as one of the most promising strategies to improve the performance of perovskite solar cells (PSCs). Among additives, perovskite nanocrystals (NCs) have a similar chemical composition and matched lattice structure with the perovskite matrix, which can effectively enhance the efficiency and stability of PSCs. However, relevant studies remain limited, and most of them focus on bromide-involved perovskite NCs, which may undergo dissolution and ion exchange within the FAPbI3 host, potentially resulting in an enlarged band gap. In this work, we employ butylamine-capped CsPbI3 NCs (BPNCs) as additives in PSCs, which can be well maintained and serve as seeds for regulating the crystallization and growth of perovskite films. The resultant perovskite film exhibits larger domain sizes and fewer grain boundaries without compromising the band gap. Moreover, BPNCs can alleviate lattice strain and reduce defect densities within the active layer. The PSCs incorporating BPNCs show a champion power conversion efficiency (PCE) of up to 25.41 %, well over both Control of 22.09 % and oleic acid/oleylamine capped CsPbI3 NC (PNC)-based devices of 23.11 %. This work illustrates the key role of nanosized seed surfaces in achieving high-performance photovoltaic devices.

9.
J Vasc Surg Venous Lymphat Disord ; 12(1): 101666, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37619711

RESUMO

BACKGROUND: Venous thromboembolism (VTE) has both environmental and genetic risk factors. It is regulated by polygenes and multisites. The polygenic risk score (PRS) has been widely used because any single genetic biomarker failed to accurately predict the genetic risk of VTE. However, no polygenic risk model has been proposed for VTE in the Chinese population. Thus, we aimed to construct a PRS model for the first episode of VTE in the Chinese population. METHODS: First, single nucleotide polymorphisms (SNPs) associated with VTE in genome-wide association studies, meta-analyses, and candidate gene studies were screened as variables for the PRS. The logarithm of the odds ratio was used to weight the variables. Second, a training set with simulated data from 1000 cases of VTE and 1000 controls was created with different genotypes and frequencies. Finally, we calculated the area under the receiver operating characteristic curve (AUC) to evaluate the discriminatory ability of the PRS model. RESULTS: We screened 53 SNPs potentially associated with the first episode of VTE in the Chinese population. The AUC of the PRS-53 model (containing 53 SNPs) was 0.748 (95% confidence interval, 0.727-0.770) in the training set. From the largest weight to the smallest weight, SNPs were incrementally added to the model to calculate the AUC for model optimization. The AUC of the PRS-10 model (containing 10 SNPs) was 0.718 (95% confidence interval, 0.696-0.740), with no statistically significant difference from the AUC for the PRS-53 model. CONCLUSIONS: The PRS-10 and PRS-53 models showed similar predictive abilities and satisfactory discriminatory power and can be used to predict the genetic risk of the first episode of VTE in the Chinese population. The simplified PRS-10 model is more efficient in clinical practice.


Assuntos
Tromboembolia Venosa , Humanos , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/genética , Estudo de Associação Genômica Ampla , Predisposição Genética para Doença , Fatores de Risco , China/epidemiologia
10.
Angew Chem Int Ed Engl ; 62(47): e202313174, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37799095

RESUMO

Chemical upcycling that catalyzes waste plastics back to high-purity chemicals holds great promise in end-of-life plastics valorization. One of the main challenges in this process is the thermodynamic limitations imposed by the high intrinsic entropy of polymer chains, which makes their adsorption on catalysts unfavorable and the transition state unstable. Here, we overcome this challenge by inducing the catalytic reaction inside mesoporous channels, which possess a strong confined ability to polymer chains, allowing for stabilization of the transition state. This approach involves the synthesis of p-Ru/SBA catalysts, in which Ru nanoparticles are uniformly distributed within the channels of an SBA-15 support, using a precise impregnation method. The unique design of the p-Ru/SBA catalyst has demonstrated significant improvements in catalytic performance for the conversion of polyethylene into high-value liquid fuels, particularly diesel. The catalyst achieved a high solid conversion rate of 1106 g ⋅ gRu -1 ⋅ h-1 at 230 °C. Comparatively, this catalytic activity is 4.9 times higher than that of a control catalyst, Ru/SiO2 , and 14.0 times higher than that of a commercial catalyst, Ru/C, at 240 °C. This remarkable catalytic activity opens up immense opportunities for the chemical upcycling of waste plastics.

11.
ACS Nano ; 17(18): 18517-18524, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37669537

RESUMO

Incorporating stimuli-responsive mechanisms into chiral assemblies of nanostructures offers numerous opportunities to create optical materials capable of dynamically modulating their chiroptical properties. In this study, we demonstrate the formation of chiral superstructures by assembling Fe3O4@polyaniline hybrid nanorods by using a gradient magnetic field. The resulting superstructures exhibit a dual response to changes in both the magnetic field and solution pH, enabling dynamic regulation of the position, intensity, and sign of its circular dichroism peaks. Such responsiveness allows for convenient control over the optical rotatory dispersion properties of the assemblies, which are further integrated into the design of a chiroptical switch that can display various colors and patterns when illuminated with light of different wavelengths and polarization states. Finally, an optical information encryption system is constructed through the controlled assembly of the hybrid nanorods to showcase the potential opportunities for practical applications brought by the resulting responsive chiral superstructures.

12.
iScience ; 26(9): 107676, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37680490

RESUMO

With the exponential expansion of electric vehicles (EVs), the disposal of Li-ion batteries (LIBs) is poised to increase significantly in the coming years. Effective recycling of these batteries is essential to address environmental concerns and tap into their economic value. Direct recycling has recently emerged as a promising solution at the laboratory level, offering significant environmental benefits and economic viability compared to pyrometallurgical and hydrometallurgical recycling methods. However, its commercialization has not been realized in the terms of financial feasibility. This perspective provides a comprehensive analysis of the obstacles that impede the practical implementation of direct recycling, ranging from disassembling, sorting, and separation to technological limitations. Furthermore, potential solutions are suggested to tackle these challenges in the short term. The need for long-term, collaborative endeavors among manufacturers, battery producers, and recycling companies is outlined to advance fully automated recycling of spent LIBs. Lastly, a smart direct recycling framework is proposed to achieve the full life cycle sustainability of LIBs.

13.
Angew Chem Int Ed Engl ; 62(38): e202308930, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37527972

RESUMO

Incorporating high-energy ultraviolet (UV) photons into photothermal catalytic processes may enable photothermal-photochemical synergistic catalysis, which represents a transformative technology for waste plastic recycling. The major challenge is avoiding side reactions and by-products caused by these energetic photons. Here, we break through the limitation of the existing photothermal conversion mechanism and propose a photochromic-photothermal catalytic system based on polyol-ligated TiO2 nanocrystals. Upon UV or sunlight irradiation, the chemically bonded polyols can rapidly capture holes generated by TiO2 , enabling photogenerated electrons to reduce Ti4+ to Ti3+ and produce oxygen vacancies. The resulting abundant defect energy levels boost sunlight-to-heat conversion efficiency, and simultaneously the oxygen vacancies facilitate polyester glycolysis by activating the nucleophilic addition-elimination process. As a result, compared to commercial TiO2 (P25), we achieve 6-fold and 12.2-fold performance enhancements under thermal and photothermal conditions, respectively, while maintaining high selectivity to high-valued monomers. This paradigm-shift strategy directs energetic UV photons for activating catalysts and avoids their interaction with reactants, opening the possibility of substantially elevating the efficiency of more solar-driven catalysis.

14.
Chem Asian J ; 18(18): e202300557, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37553862

RESUMO

Hydrothermal-based direct regeneration of spent Li-ion battery (LIB) cathodes has garnered tremendous attention for its simplicity and scalability. However, it is heavily reliant on manual disassembly to ensure the high purity of degraded cathode powders, and the quality of regenerated materials. In reality, degraded cathodes often contain residual components of the battery, such as binders, current collectors, and graphite particles. Thorough investigation is thus required to understand the effects of these impurities on hydrothermal-based direct regeneration. In this study, we focus on isolating the effects of aluminum (Al) scraps on the direct regeneration process. We found that Al metal can be dissolved during the hydrothermal relithiation process. Even when the cathode material contains up to 15 wt.% Al scraps, no detrimental effects were observed on the recovered structure, chemical composition, and electrochemical performance of the regenerated cathode material. The regenerated NCM cathode can achieve a capacity of 163.68 mAh/g at 0.1 C and exhibited a high-capacity retention of 85.58 % after cycling for 200 cycles at 0.5 C. Therefore, the hydrothermal-based regeneration method is effective in revitalizing degraded cathode materials, even in the presence of notable Al impurity content, showing great potential for industrial applications.

15.
Research (Wash D C) ; 6: 0032, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37040499

RESUMO

Catalytic hydrogenolysis of end-of-life polyolefins can produce value-added liquid fuels and therefore holds great promises in plastic waste reuse and environmental remediation. The major challenge limiting the recycling economic benefit is the severe methanation (usually >20%) induced by terminal C-C cleavage and fragmentation in polyolefin chains. Here, we overcome this challenge by demonstrating that Ru single-atom catalyst can effectively suppress methanation by inhibiting terminal C-C cleavage and preventing chain fragmentation that typically occurs on multi-Ru sites. The Ru single-atom catalyst supported on CeO2 shows an ultralow CH4 yield of 2.2% and a liquid fuel yield of over 94.5% with a production rate of 314.93 gfuels gRu -1 h-1 at 250 °C for 6 h. Such remarkable catalytic activity and selectivity of Ru single-atom catalyst in polyolefin hydrogenolysis offer immense opportunities for plastic upcycling.

16.
J Endovasc Ther ; : 15266028231158294, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36891634

RESUMO

PURPOSE: This study aimed to develop and internally validate nomograms for predicting restenosis after endovascular treatment of lower extremity arterial diseases. MATERIALS AND METHODS: A total of 181 hospitalized patients with lower extremity arterial disease diagnosed for the first time between 2018 and 2019 were retrospectively collected. Patients were randomly divided into a primary cohort (n=127) and a validation cohort (n=54) at a ratio of 7:3. The least absolute shrinkage and selection operator (LASSO) regression was used to optimize the feature selection of the prediction model. Combined with the best characteristics of LASSO regression, the prediction model was established by multivariate Cox regression analysis. The predictive models' identification, calibration, and clinical practicability were evaluated by the C index, calibration curve, and decision curve. The prognosis of patients with different grades was compared by survival analysis. Internal validation of the model used data from the validation cohort. RESULTS: The predictive factors included in the nomogram were lesion site, use of antiplatelet drugs, application of drug coating technology, calibration, coronary heart disease, and international normalized ratio (INR). The prediction model demonstrated good calibration ability, and the C index was 0.762 (95% confidence interval: 0.691-0.823). The C index of the validation cohort was 0.864 (95% confidence interval: 0.801-0.927), which also showed good calibration ability. The decision curve shows that when the threshold probability of the prediction model is more significant than 2.5%, the patients benefit significantly from our prediction model, and the maximum net benefit rate is 30.9%. Patients were graded according to the nomogram. Survival analysis found that there was a significant difference in the postoperative primary patency rate between patients of different classifications (log-rank p<0.001) in both the primary cohort and the validation cohort. CONCLUSION: We developed a nomogram to predict the risk of target vessel restenosis after endovascular treatment by considering information on lesion site, postoperative antiplatelet drugs, calcification, coronary heart disease, drug coating technology, and INR. CLINICAL IMPACT: Clinicians can grade patients after endovascular procedure according to the scores of the nomograms and apply intervention measures of different intensities for people at different risk levels. During the follow-up process, an individualized follow-up plan can be further formulated according to the risk classification. Identifying and analyzing risk factors is essential for making appropriate clinical decisions to prevent restenosis.

17.
J Environ Sci Health B ; 58(2): 150-157, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36728597

RESUMO

A modified QuEChERS pretreatment method and LC-MS/MS technique were performed to simultaneously determine four pesticide (Hexachlorophene, Dinex, Dinosam, Dinoterb) residues in agricultural products. Through the optimization of LC-MS/MS detection parameters in SIM mode, the optimal instrument conditions are obtained. The modified QuEChERS method was used to pretreat the samples. Solid phase extractants PSA, C18 and GCB were used for sample purification. The research results showed that the correlation coefficients of the four pesticides were all greater than 0.991, which had a good linear relationship. The limits of quantitation (LOQ) of the four pesticides were 0.05-0.56 µg/kg. The recoveries were 70.51-113.20% with relative standard deviations (RSDS) of 1.6-11.2%. The developed method can provide reliable data support for the subsequent simultaneous detection of these four pesticides.


Assuntos
Resíduos de Praguicidas , Praguicidas , Praguicidas/análise , Cromatografia Líquida/métodos , Resíduos de Praguicidas/análise , Espectrometria de Massas em Tandem/métodos
18.
Anal Chem ; 95(9): 4261-4265, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36802510

RESUMO

ß-d-Glucuronidase (GUS) plays a pivotal role in both clinical treatment assessment and environmental monitoring. Existing tools for GUS detection suffer from (1) poor continuity due to a gap between the optimal pH of the probes and the enzyme and (2) diffusion from the detection site due to lack of an anchoring structure. Here we report a novel GUS pH-matching and endoplasmic reticulum-anchoring strategy for GUS recognition. The new fluorescent probe tool was termed ERNathG, which was designed and synthesized with ß-d-glucuronic acid as the GUS-specific recognition site and 4-hydroxy-1,8-naphthalimide as a fluorescence reporting group, with a p-toluene sulfonyl as an anchoring group. This probe enabled the continuous and anchored detection of GUS without pH-adjustment for the related assessment of common cancer cell lines and gut bacteria. The probe's properties are far superior to those of commonly used commercial molecules.


Assuntos
Corantes Fluorescentes , Neoplasias , Humanos , Corantes Fluorescentes/química , Glucuronidase/química , Bactérias/metabolismo , Ácido Glucurônico
19.
Small ; 19(17): e2207312, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36725364

RESUMO

All-inorganic lead halide perovskite nanocrystals (NCs) emerge as a rising star in photovoltaic fields on account of their excellent optoelectronic properties. However, it still remains challenging to further promote photovoltaic efficiency due to the susceptible surface and inevitable vacancies. Here, this work reports a 3D/2D core/shell perovskite heterojunction based on CsPbI3 NCs and its performance in solar cells. The guanidinium (GA+ ) rich 2D nanoshells can significantly passivate surface trap states and lower the capping ligand density, resulting in improved photoelectric properties and carrier transport and diminished nonradiative recombination centers via the hydrogen bonds from amino groups in GA+ ions. Consequently, an outstanding power conversion efficiency (PCE) of up to 15.53% is realized, substantially higher than the control device (13.77%). This work highlights the importance of surface chemistry and offers a feasible avenue to achieve high-performance perovskite NCs-based optoelectronic devices.

20.
Nano Lett ; 23(2): 685-693, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36594847

RESUMO

While tuning the electronic structure of Pt can thermodynamically alleviate CO poisoning in direct methanol fuel cells, the impact of interactions between intermediates on the reaction pathway is seldom studied. Herein, we contrive a PtBi model catalyst and realize a complete inhibition of the CO pathway and concurrent enhancement of the formate pathway in the alkaline methanol electrooxidation. The key role of Bi is enriching OH adsorbates (OHad) on the catalyst surface. The competitive adsorption of CO adsorbates (COad) and OHad at Pt sites, complementing the thermodynamic contribution from alloying Bi with Pt, switches the intermediate from COad to formate that circumvents CO poisoning. Hence, 8% Bi brings an approximately 6-fold increase in activity compared to pure Pt nanoparticles. This notion can be generalized to modify commercially available Pt/C catalysts by a microwave-assisted method, offering opportunities for the design and practical production of CO-tolerance electrocatalysts in an industrial setting.

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