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1.
Sci Total Environ ; 928: 172427, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38614337

RESUMO

This research analyzed the real-world NOx and particle number (PN) emissions of 21 China VI heavy-duty diesel trucks (HDDTs). On-road emission conformity was first evaluated with portable emission measurement system (PEMS). Only 76.19 %, 71.43 % and 61.90 % of the vehicles passed the NOx test, PN test and both tests, respectively. The impacts of vehicle features including exhaust gas recirculation (EGR) equipment, mileage and tractive tonnage were then assessed. Results demonstrated that EGR helped reducing NOx emission factors (EFs) while increased PN EFs. Larger mileages and tractive tonnages corresponded to higher NOx and PN EFs, respectively. In-depth analyses regarding the influences of operating conditions on emissions were conducted with both numerical comparisons and statistical tests. Results proved that HDDTs generated higher NOx EFs under low speeds or large vehicle specific powers (VSPs), and higher PN EFs under high speeds or small VSPs in general. In addition, unqualified vehicles generated significantly higher NOx EFs than qualified vehicles on freeways or under speed≥40 km/h, while significant higher PN EFs were generated on suburban roads, freeways or under operating modes with positive VSPs by unqualified vehicles. The reliability and accuracy of on-board diagnostic (OBD) NOx data were finally investigated. Results revealed that 43 % of the test vehicles did not report reliable OBD data. Correlation analyses between OBD NOx and PEMS measurements further demonstrated that the consistency of instantaneous concentrations were generally low. However, sliding window averaged concentrations show better correlations, e.g., the Pearson correlation coefficients on 20s-window averaged concentrations exceeded 0.85 for most vehicles. The research results provide valuable insights into emission regulation, e.g., focusing more on medium- to high-speed operations to identify unqualified vehicles, setting higher standards to improve the quality of OBD data, and adopting window averaged OBD NOx concentrations in evaluating vehicle emission performance.

2.
Small ; : e2400774, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38616778

RESUMO

Capacitive carbon cathodes deliver great potential for zinc-ion hybrid capacitors (ZHCs) due to their resource abundance and structural versatility. However, the dimension mismatch between the micropores of carbons and hydrated Zn2+ ions often results in unsatisfactory charge storage capability. Here well-arranged heterodiatomic carbon superstructures are reported with compatible pore dimensions for activating Zn2+ ions, initiated by the supramolecular self-assembly of 1,3,5-triazine-2,4,6-triamine and cyanuric acid via in-plane hydrogen-bonds and out-of-plane π-π interactions. Flower-shaped carbon superstructures expose more surface-active motifs, continuous charge-transport routes, and more importantly, well-developed pores. The primary subnanopores of 0.82 nm are size-exclusively accessible for solvated Zn2+ ions (0.86 nm) to maximize spatial charge storage, while rich mesopores (1-3 nm) allow for high-kinetics ion migration with a low activation energy. Such favorable superstructure cathodes contribute to all-round performance improvement for ZHCs, including high energy density (158 Wh kg-1), fast-charging ability (50 A g-1), and excellent cyclic lifespan (100 000 cycles). An anion-cation hybrid charge storage mechanism is elucidated for superstructure cathode, which entails alternate physical uptake of Zn2+/CF3SO3 - at electroactive pores and bipedal chemical binding of Zn2+ to electronegative carbonyl/pyridine motifs. This work expands the design landscape of carbon superstructures for advanced energy storage.

3.
Adv Sci (Weinh) ; 11(19): e2310319, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38477446

RESUMO

Zinc-organic batteries (ZOBs) are receiving widespread attention as up-and-coming energy-storage systems due to their sustainability, operational safety and low cost. Charge carrier is one of the critical factors affecting the redox kinetics and electrochemical performances of ZOBs. Compared with conventional large-sized and sluggish Zn2+ storage, non-metallic charge carriers with small hydrated size and light weight show accelerated interfacial dehydration and fast reaction kinetics, enabling superior electrochemical metrics for ZOBs. Thus, it is valuable and ongoing works to build better ZOBs with non-metallic ion storage. In this review, versatile non-metallic cationic (H+, NH4 +) and anionic (Cl-, OH-, CF3SO3 -, SO4 2-) charge carriers of ZOBs are first categorized with a brief comparison of their respective physicochemical properties and chemical interactions with redox-active organic materials. Furthermore, this work highlights the implementation effectiveness of non-metallic ions in ZOBs, giving insights into the impact of ion types on the metrics (capacity, rate capability, operation voltage, and cycle life) of organic cathodes. Finally, the challenges and perspectives of non-metal-ion-based ZOBs are outlined to guild the future development of next-generation energy communities.

4.
Chem Sci ; 15(12): 4322-4330, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38516081

RESUMO

Dendrite growth and parasitic reactions of a Zn metal anode in aqueous media hinder the development of up-and-coming Zn-ion batteries. Optimizing the crystal growth after Zn nucleation is promising to enable stable cyclic performance of the anode, but directly regulating specific crystal plane growth for homogenized Zn electrodeposition remains highly challenging. Herein, a perfluoropolymer (Nafion) is introduced into an aqueous electrolyte to activate a thermodynamically ultrastable Zn/electrolyte interface for long-term Zn-ion batteries. The low adsorption energy (-2.09 eV) of Nafion molecules on Zn metal ensures the in situ formation of a Nafion-nanofilm during the first charge process. This ultrathin artificial solid electrolyte interface with zincophilic -SO3- groups guides the directional Zn2+ electrodeposition along the (002) crystal surface even at high current density, yielding a dendrite-free Zn anode. The synergic Zn/electrolyte interphase electrochemistry contributes an average coulombic efficiency of 99.71% after 4500 cycles for Zn‖Cu cells, and Zn‖Zn cells achieve an ultralong lifespan of over 7000 h at 5 mA cm-2. Besides, Zn‖MnO2 cells operate well over 3000 cycles. Even at -40 °C, Zn‖Zn cells achieve stable Zn2+ plating/stripping for 1200 h.

5.
Nanoscale ; 16(8): 4004-4013, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38328885

RESUMO

Raman scattering provides essential insights into phonons, electronic structures and electron-phonon coupling within solids through the intensity of Raman peaks, which cannot be easily quantified using the classical bond polarizability model. The interlayer bond polarizability model (IBPM) had been developed to understand the Raman intensity of layer-breathing modes (LBMs) in two-dimensional materials. However, the quantitative understanding of the LBM intensity of a van der Waals heterostructure (vdWH) remains challenging. Here, in polynary vdWHs comprising twisted multilayer graphene (tMLG), MoS2 and hBN, we observed a series of LBMs, whose intensity is markedly dependent on the excitation energy and twist angle of the tMLG constituent. An improved IBPM is proposed to quantitatively understand the Raman intensity of LBMs in the tMLG-based vdWHs, including the emergence or absence of a specific LBM when the excitation energy is resonant with the electronic states of tMLG or MoS2 constituents. This work underscores the significant potential of the improved IBPM in accurately understanding and predicting the intensity profile of LBM in polynary vdWHs, even for the case of Raman scattering with excitation energies selectively resonant with the electronic states of the corresponding specific constituents.

6.
Angew Chem Int Ed Engl ; 63(16): e202401049, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38372434

RESUMO

Bipolar organics fuse the merits of n/p-type redox reactions for better Zn-organic batteries (ZOBs), but face the capacity plafond due to low density of active units and single-electron reactions. Here we report multielectron redox-bipolar tetranitroporphyrin (TNP) with quadruple two-electron-accepting n-type nitro motifs and dual-electron-donating p-type amine moieties towards high-capacity-voltage ZOBs. TNP cathode initiates high-kinetics, hybrid anion-cation 10e- charge storage involving four nitro sites coordinating with Zn2+ ions at low potential and two amine species coupling with SO4 2- ions at high potential. Consequently, Zn||TNP battery harvests high capacity (338 mAh g-1), boosted average voltage (1.08 V), and outstanding energy density (365 Wh kg-1 TNP). Moreover, the extended π-conjugated TNP macrocycle achieves anti-dissolution in electrolytes, prolonging the battery life to 50,000 cycles at 10 A g-1 with 71.6 % capacity retention. This work expands the chemical landscape of multielectron redox-bipolar organics for state-of-the-art ZOBs.

7.
BMC Plant Biol ; 24(1): 49, 2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38216904

RESUMO

BACKGROUND: Trees have developed a broad spectrum of molecular mechanisms to counteract oxidative stress. Secondary metabolites via phenolic compounds emblematized the hidden bridge among plant kingdom, human health, and oxidative stress. Although studies have demonstrated that abiotic stresses can increase the production of medicinal compounds in plants, research comparing the efficiency of these stresses still needs to be explored. Thus, the present research paper provided an exhaustive comparative metabolomic study in Dalbergia odorifera under salinity (ST) and waterlogging (WL). RESULTS: High ST reduced D. odorifera's fresh biomass compared to WL. While WL only slightly affected leaf and vein size, ST had a significant negative impact. ST also caused more significant damage to water status and leaflet anatomy than WL. As a result, WL-treated seedlings exhibited better photosynthesis and an up-regulation of nonenzymatic pathways involved in scavenging reactive oxygen species. The metabolomic and physiological responses of D. odorifera under WL and salinity ST stress revealed an accumulation of secondary metabolites by the less aggressive stress (WL) to counterbalance the oxidative stress. Under WL, more metabolites were more regulated compared to ST. ST significantly altered the metabolite profile in D. odorifera leaflets, indicating its sensitivity to salinity. WL synthesized more metabolites involved in phenylpropanoid, flavone, flavonol, flavonoid, and isoflavonoid pathways than ST. Moreover, the down-regulation of L-phenylalanine correlated with increased p-coumarate, caffeate, and ferulate associated with better cell homeostasis and leaf anatomical indexes under WL. CONCLUSIONS: From a pharmacological and medicinal perspective, WL improved larger phenolics with therapeutic values compared to ST. Therefore, the data showed evidence of the crucial role of medical tree species' adaptability on ROS detoxification under environmental stresses that led to a significant accumulation of secondary metabolites with therapeutic value.


Assuntos
Dalbergia , Humanos , Dalbergia/metabolismo , Salinidade , Plantas/metabolismo , Antioxidantes/metabolismo , Fotossíntese
8.
J Hypertens ; 42(5): 816-827, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38165021

RESUMO

Thoracic aortic aneurysm and dissection (TAAD) is a life-threatening disease and currently there is no pharmacological therapy. Sympathetic nerve overactivity plays an important role in the development of TAAD. Sympathetic innervation is mainly controlled by nerve growth factor (NGF, a key neural chemoattractant) and semaphoring 3A (Sema3A, a key neural chemorepellent), while the roles of these two factors in aortic sympathetic innervation and especially TAAD are unknown. We hypothesized that genetically manipulating the NGF/Sema3A ratio by the Ngf -driven Sema3a expression approach may reduce aortic sympathetic nerve innervation and mitigate TAAD progression. A mouse strain of Ngf gene-driven Sema3a expression (namely NgfSema3a/Sema3a mouse) was established by inserting the 2A-Sema3A expression frame to the Ngf terminating codon using CRISPR/Cas9 technology. TAAD was induced by ß-aminopropionitrile monofumarate (BAPN) both in NgfSema3a/Sema3a mice and wild type (WT) littermates. Contrary to our expectation, the BAPN-induced TAAD was severer in NgfSema3a/Sema3a mice than in wild-type (WT) mice. In addition, NgfSema3a/Sema3a mice showed higher aortic sympathetic innervation, inflammation and extracellular matrix degradation than the WT mice after BAPN treatment. The aortic vascular smooth muscle cells isolated from NgfSema3a/Sema3a mice and pretreated with BAPN in vivo for two weeks showed stronger capabilities of proliferation and migration than that from the WT mice. We conclude that the strategy of Ngf -driven Sema3a expression cannot suppress but worsens the BAPN-induced TAAD. By investigating the aortic phenotype of NgfSema3a/Sema3a mouse strain, we unexpectedly find a path to exacerbate BAPN-induced TAAD which might be useful in future TAAD studies.


Assuntos
Aneurisma da Aorta Torácica , Dissecção Aórtica , Azidas , Desoxiglucose , Animais , Camundongos , Aminopropionitrilo/efeitos adversos , Aneurisma da Aorta Torácica/genética , Aneurisma da Aorta Torácica/induzido quimicamente , Aneurisma da Aorta Torácica/metabolismo , Desoxiglucose/análogos & derivados , Modelos Animais de Doenças , Fator de Crescimento Neural/genética , Fator de Crescimento Neural/efeitos adversos , Semaforina-3A/genética
9.
Nat Commun ; 15(1): 586, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38233393

RESUMO

X-chromosomal genetic variants are understudied but can yield valuable insights into sexually dimorphic human traits and diseases. We performed a sex-stratified cross-ancestry X-chromosome-wide association meta-analysis of seven kidney-related traits (n = 908,697), identifying 23 loci genome-wide significantly associated with two of the traits: 7 for uric acid and 16 for estimated glomerular filtration rate (eGFR), including four novel eGFR loci containing the functionally plausible prioritized genes ACSL4, CLDN2, TSPAN6 and the female-specific DRP2. Further, we identified five novel sex-interactions, comprising male-specific effects at FAM9B and AR/EDA2R, and three sex-differential findings with larger genetic effect sizes in males at DCAF12L1 and MST4 and larger effect sizes in females at HPRT1. All prioritized genes in loci showing significant sex-interactions were located next to androgen response elements (ARE). Five ARE genes showed sex-differential expressions. This study contributes new insights into sex-dimorphisms of kidney traits along with new prioritized gene targets for further molecular research.


Assuntos
Androgênios , Estudo de Associação Genômica Ampla , Humanos , Masculino , Feminino , Androgênios/genética , Rim , Cromossomos Humanos X/genética , Elementos de Resposta , Polimorfismo de Nucleotídeo Único , Predisposição Genética para Doença , Tetraspaninas/genética
10.
Plant Physiol ; 194(4): 2301-2321, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38048404

RESUMO

Field and greenhouse studies attempting to describe the molecular responses of plant species under waterlogging (WL) combined with salinity (ST) are almost nonexistent. We integrated transcriptional, metabolic, and physiological responses involving several crucial transcripts and common differentially expressed genes and metabolites in fragrant rosewood (Dalbergia odorifera) leaflets to dissect plant-specific molecular responses and patterns under WL combined with ST (SWL). We discovered that the synergistic pattern of the transcriptional response of fragrant rosewood under SWL was exclusively characterized by the number of regulated transcripts. The response patterns under SWL based on transcriptome and metabolome regulation statuses revealed different patterns (additive, dominant, neutral, minor, unilateral, and antagonistic) of transcripts or metabolites that were commonly regulated or expressed uniquely under SWL. Under SWL, the synergistic transcriptional response of several functional gene subsets was positively associated with several metabolomic and physiological responses related to the shutdown of the photosynthetic apparatus and the extensive degradation of starch into saccharides through α-amylase, ß-amylase, and α-glucosidase or plastoglobuli accumulation. The dissimilarity between the regulation status and number of transcripts in plants under combined stresses led to nonsynergistic responses in several physiological and phytohormonal traits. As inferred from the impressive synergistic transcriptional response to morpho-physiological changes, combined stresses exhibited a gradually decreasing effect on the changes observed at the molecular level compared to those in the morphological one. Here, by characterizing the molecular responses and patterns of plant species under SWL, our study considerably improves our understanding of the molecular mechanisms underlying combined stress.


Assuntos
Dalbergia , Dalbergia/genética , Salinidade , Transcriptoma/genética , Fenótipo , Metabolômica , Estresse Fisiológico/genética
11.
Angew Chem Int Ed Engl ; 63(3): e202316835, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38010854

RESUMO

Compared with Zn2+ storage, non-metallic charge carrier with small hydrated size and light weight shows fast dehydration and diffusion kinetics for Zn-organic batteries. Here we first report NH4 + /H+ co-storage in self-assembled organic superstructures (OSs) by intermolecular interactions of p-benzoquinone (BQ) and 2, 6-diaminoanthraquinone (DQ) polymer through H-bonding and π-π stacking. BQ-DQ OSs exhibit exposed quadruple-active carbonyl motifs and super electron delocalization routes, which are redox-exclusively coupled with high-kinetics NH4 + /H+ but exclude sluggish and rigid Zn2+ ions. A unique 4e- NH4 + /H+ co-coordination mechanism is unravelled, giving BQ-DQ cathode high capacity (299 mAh g-1 at 1 A g-1 ), large-current tolerance (100 A g-1 ) and ultralong life (50,000 cycles). This strategy further boosts the capacity to 358 mAh g-1 by modulating redox-active building units, giving new insights into ultra-fast and stable NH4 + /H+ storage in organic materials for better Zn batteries.

12.
J Colloid Interface Sci ; 658: 856-864, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38157610

RESUMO

Understanding the self-stacking interactions in precursors can facilitate the preparation of high-performance carbon materials and promote the commercial application of zinc ion hybrid capacitors (ZIHCs). Here, a π-conjugated molecule mediated pyrolysis strategy is presented to prepare carbon materials. Taking intermolecular force simulation (reduced density gradient plots) as a guide, the relationship between the self-stacking interactions in π-conjugated molecules and the structural parameters of carbon materials can be extrapolated. The resultant self-doped hierarchical porous carbons (NHPCs) derived from 1, 8, 4, 5-naphthalenetetracarboxdiimide with suitable self-stacking interactions empower the highest specific surface areas (2038 m2/g) and surface opening macropores. The NHPCs-based ZIHCs deliver a high capacity of 220 mAh/g, a high energy density of 149.5 Wh kg-1 and a super-stable cycle lifespan with 93.2 % capacity retention after 200, 000 cycles. The excellent electrochemical performance roots in the superior hierarchical porous structure with surface opening macropores, which guarantees the structural stability of carbon cathodes upon repeated rounds. Meanwhile, the heteroatom doping further relieves the kinetics concern of Zn2+ uptake/removal to enhance O-Zn-N binding particularly at high discharge currents. Besides, the proton-assisted Zn2+ dual-ion storage mechanism plays an essential role in the energy storage process. This work demonstrates a facile synthesis method and advances the fundamental understanding of its dual-ion storage mechanism.

13.
Med Sci Monit ; 29: e943586, 2023 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-38145290

RESUMO

The Editors of Medical Science Monitor wish to inform you that the above manuscript has been retracted from publication due to concerns with the credibility and originality of the study, the manuscript content, and the Figure images. Reference: Mei Mei Guan, Qun Xian Rao, Miao Ling Huang, Li Juan Wang, Shao Dan Lin, Qing Chen, Chang Hao Liu. Long Noncoding RNA TP73-AS1 Targets MicroRNA-329-3p to Regulate Expression of the SMAD2 Gene in Human Cervical Cancer Tissue and Cell Lines. Med Sci Monit, 2019; 25: 8131-8141. DOI: 10.12659/MSM.916292.

14.
Environ Sci Pollut Res Int ; 30(49): 108085-108106, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37747610

RESUMO

The introduction of China's double carbon target has led to a new stage in the development of China's low-carbon economy, while the development of China's green finance is also facing new challenges. Based on the determining of the relationship between low-carbon economy and green finance, this study selected the Yangtze River Delta city cluster of China, an exemplary region for the development of low-carbon economy and green finance, constructed a multi-level comprehensive index system covering two systems of low-carbon economy and green finance and conducted a coupled and coordinated relationship analysis based on the panel data of green finance and low-carbon economy-related indicators from 2016 to 2020. The empirical results showed that the interaction between the low-carbon economy system and the green finance system in the Yangtze River Delta region gradually weakened during 2016-2020, and the mechanism of interaction between the two systems has not been fully developed and utilized. Overall, the development of green finance in all four provinces and cities has not gained sufficient momentum, which is a constraint to the coupled and coordinated development of low-carbon economy and green finance in the four provinces and cities in the Yangtze River Delta. Zhejiang Province and Jiangsu Province performed better in terms of the scale of green finance and the use of diversified instruments, while Shanghai City performed better in terms of low-carbon economy, whereas Anhui Province needs to improve in both low-carbon economy and green finance.


Assuntos
Carbono , Cabeça , China , Cidades , Pesquisa Empírica , Desenvolvimento Econômico
15.
Adv Mater ; 35(46): e2306330, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37737448

RESUMO

Due to its inversion-broken triple helix structure and the nature of Weyl semiconductor, 2D Tellurene (2D Te) is promising to possess a strong nonlinear optical response in the infrared region, which is rarely reported in 2D materials. Here, a giant nonlinear infrared response induced by large Berry curvature dipole (BCD) is demonstrated in the Weyl semiconductor 2D Te. Ultrahigh second-harmonic generation response is acquired from 2D Te with a large second-order nonlinear optical susceptibility (χ(2) ), which is up to 23.3 times higher than that of monolayer MoS2 in the range of 700-1500 nm. Notably, distinct from other 2D nonlinear semiconductors, χ(2) of 2D Te increases extraordinarily with increasing wavelength and reaches up to 5.58 nm V-1 at ≈2300 nm, which is the best infrared performance among the reported 2D nonlinear materials. Large χ(2) of 2D Te also enables the high-intensity sum-frequency generation with an ultralow continuous-wave (CW) pump power. Theoretical calculations reveal that the exceptional performance is attributed to the presence of large BCD located at the Weyl points of 2D Te. These results unravel a new linkage between Weyl semiconductor and strong optical nonlinear responses, rendering 2D Te a competitive candidate for highly efficient nonlinear 2D semiconductors in the infrared region.

16.
Phys Chem Chem Phys ; 25(38): 26236-26244, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37740341

RESUMO

Halide perovskites with ultralow thermal conductivity have emerged as promising candidates for thermoelectric materials. We study the lattice dynamics and thermoelectric properties of cubic all-inorganic lead halide perovskites CsPbX3 (X = Cl, Br, and I) through first-principles calculations. Combined with self-consistent phonon theory, we have successfully renormalized the phonon frequency using a quartic anharmonic term, allowing us to accurately reproduce the phonon dispersion of the high-temperature cubic phase of CsPbX3 without any imaginary frequencies. Cubic CsPbX3 exhibit ultralow lattice thermal conductivities (0.61-1.71 Wm-1 K-1) at room temperature. Because of the strong quartic anharmonic renormalization and hardening of the soft modes, the lattice thermal conductivities of cubic CsPbX3 all exhibit weak temperature dependence. Notably, CsPbCl3 exhibits remarkably high thermal conductivity and a long phonon lifetime. This can be attributed to the smallest atomic mean square displacement and the weakest tilting and distortions of PbCl6 octahedra, resulting from the strongest Pb-Cl covalent bonding. Furthermore, the maximum ZT value of 0.63 at 900 K is obtained for the n-type CsPbBr3.

17.
Nanoscale ; 15(31): 12880-12888, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37477377

RESUMO

Organic-inorganic low-dimensional layered metal-halide perovskites are semiconductors in which the optoelectronic properties can be tuned by the material composition and the design of the layered architecture. While the electronic band structure is mainly determined by the inorganic octahedra lattice, the binding and conformation of the organic cations induces related lattice distortions that can break the symmetry and lead to the splitting of the exciton energy levels, and influence the dielectric confinement. Furthermore, organic-induced lattice deformations lead to offsets in k-space (where k is the wavevector) that go along with the exciton energy level splitting. Hence, the electronic transitions between these levels require the momentum contribution of phonons, and contributions of phonons in the exciton recombination dynamics result in thermal broadening of the emission linewidth. In this work, we investigate the band-edge emission of two-dimensional Ruddlesden-Popper lead-bromide perovskites synthesized with different organic cations that vary in their binding head group and their alkyl chain length. We find several peaks in the low-temperature photoluminescence spectra, and the number of peaks in the band-edge emission and their decay dynamics depend strongly on the type of organic cation in the material, which we relate to the difference in the inorganic lattice distortions that the cations induce. For two-dimensional layered perovskites with mainly in-plane distortions, induced by short primary ammonium molecules, we find a two-fold splitting of the band edge emission at low temperatures. If also out-of-plane distortions are present, as for the long-chain primary ammoniums, a three-fold splitting is observed. Interestingly, the low-energy peaks of the split series merge into the highest energy peak with increasing temperature. Thermal broadening analysis of the temperature-dependent photoluminescence linewidth in the structures with out-of-plane distortions yields energies that are larger than those reported for the inorganic lattice phonons. This indicates the involvement of either high-frequency oscillations involving the organic cations, or the broadening might be related to higher order phonon scattering processes in the excitonic recombination process. The strong directionality of the phonon modes in the octahedral lattice could promote the involvement of multiple electron-phonon scattering processes in the exciton relaxation dynamics, for example involving modes with orthogonal directionality.

18.
Angew Chem Int Ed Engl ; 62(38): e202309446, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37507839

RESUMO

Organic small molecules as high-capacity cathodes for Zn-organic batteries have inspired numerous interests, but are trapped by their easy-dissolution in electrolytes. Here we knit ultrastable lock-and-key hydrogen-bonding networks between 2, 7-dinitropyrene-4, 5, 9, 10-tetraone (DNPT) and NH4 + charge carrier. DNPT with octuple-active carbonyl/nitro centers (H-bond acceptor) are redox-exclusively accessible for flexible tetrahedral NH4 + ions (H-bond donator) but exclude larger and rigid Zn2+ , due to a lower activation energy (0.14 vs. 0.31 eV). NH4 + coordinated H-bonding chemistry conquers the stability barrier of DNPT in electrolyte, and gives fast diffusion kinetics of non-metallic charge carrier. A stable two-step 4e- NH4 + coordination with DNPT cathode harvests a high capacity (320 mAh g-1 ), a high-rate capability (50 A g-1 ) and an ultralong life (60,000 cycles). This finding points to a new paradigm for H-bond stabilized organic small molecules to design advanced zinc batteries.

19.
ACS Appl Mater Interfaces ; 15(29): 35380-35390, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37440355

RESUMO

Designing zincophilic and stable carbon nanostructures is critical for Zn-ion storage with superior capacitive activity and durability. Here, we report solvent-guided Lewis acid-base self-assembly to customize heterodiatomic carbon nanotubes, triggered by the reaction between iron chloride and α,α'-dichloro-p-xylene. In this strategy, modulating the solvent-precursor interaction through the optimization of solvent formula stimulates differential thermodynamic solubilization, growth kinetics, and self-assembly behaviors of Lewis polymeric chains, thereby accurately tailoring carbon nanoarchitectures to evoke superior Zn-ion storage. Featured with open hollow interiors and porous tubular topologies, the solvent-optimized carbon nanotubes allow low ion-migration barriers to deeply access the built-in zincophilic sites by high-kinetics physical Zn2+/CF3SO3- adsorption and robust chemical Zn2+ redox with pyridine/carbonyl motifs, which maximizes the spatial capacitive charge storage density. Thus, as-designed heterodiatomic carbon nanotube cathodes provide all-round improvement in Zn-ion storage, including a high energy density (140 W h kg-1), a large current activity (100 A g-1), and an exceptional long-term cyclability (100,000 cycles at 50 A g-1). This study provides appealing insights into the solvent-mediated Lewis pair self-assembly design of nanostructured carbons toward advanced Zn-ion energy storage.

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