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1.
Inorg Chem ; 63(24): 11146-11154, 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38838348

ABSTRACT

Surface ligands play crucial roles in modifying the properties of metal nanoclusters and stabilizing atomically precise structures, and also serve as vital linkers for constructing cluster-based coordination polymers. In this study, we present the results of the solvothermal synthesis of eight novel copper alkynyl clusters incorporating pyridine ligands using a one-pot method. The resulting compounds underwent characterization through elemental analysis, Fourier transform infrared (FT-IR) spectroscopy, powder X-ray diffraction (PXRD), and single-crystal X-ray diffraction (SCXRD). Our observations revealed that distinct pyridine ligands with varying lengths and coordination sites exert significant influence on the structure and dimensionality of the clusters. The structural diversity of these clusters led to the formation of one-dimensional (1D), two-dimensional (2D), or dimer arrangements linked by seven pyridine bridging ligands. Remarkably, these complexes exhibited unique UV-vis absorption and photoluminescence properties, which were influenced by the specific bridging ligand and structural framework. Furthermore, density functional theory (DFT) calculations demonstrated the capability of the conjugated system in the pyridine ligand to impact the band gap of clusters. This study not only unveils the inherent structural diversity in coordination polymers based on copper alkynyl clusters but also offers valuable insights into harnessing ligand engineering for structural and property modulation.

2.
Angew Chem Int Ed Engl ; 63(20): e202401206, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38469979

ABSTRACT

Alloying nanoclusters (NCs) has emerged as a widely explored and versatile strategy for tailoring tunable properties, facilitating in-depth atomic-level investigations of structure-property correlations. In this study, we have successfully synthesized six atomically precise copper NCs alloyed with Group 10 metals (Pd or Pt). Notably, the Pd0 or Pt0 atom situated at the center of the distorted hexagonal antiprism Pd0/Pt0@Cu12 cage, coordinated with twelve Cu+ and two tBuC≡C- ligands. Moreover, ligand exchange strategies demonstrated the potential for Cl- and Br- to replace one or two alkynyl ligands positioned at the top or side of the NCs. The chirality exhibited by these racemic NCs is primarily attributed to the involvement of halogens and a chiral (Pd/Pt)@Cu18 skeleton. Furthermore, all the NCs exhibit near-infrared (NIR) luminescence, characterized by emission peaks at 705-755 nm, lifetimes ranging from 6.630 to 9.662 µs, and absolute photoluminescence quantum yields (PLQYs) of 1.75 %-2.52 % in their crystalline state. The experimental optical properties of these NCs are found to be in excellent agreement with the results of theoretical calculations. These alloy NCs not only offer valuable insights into the synthesis of Pd0/Pt0-Cu alloy NCs, but also bridge the gap in understanding the structure-luminescence relationships of Pd0/Pt0-Cu molecules.

3.
Chem Sci ; 14(44): 12637-12644, 2023 Nov 15.
Article in English | MEDLINE | ID: mdl-38020372

ABSTRACT

A comparative study of structure-property relationships in isomeric and isostructural atomically precise clusters is an ideal approach to unravel their fundamental properties. Herein, seven high-nuclearity copper(i) alkynyl clusters utilizing template-assisted strategies were synthesized. Spherical Cu36 and Cu56 clusters are formed with a [M@(V/PO4)6] (M: Cu2+, Na+, K+) skeleton motif, while peanut-shaped Cu56 clusters feature four separate PO4 templates. Experiments and theoretical calculations suggested that the photophysical properties of these clusters are dependent on both the inner templates and outer phosphonate ligands. Phenyl and 1-naphthyl phosphate-protected clusters exhibited enhanced emission features attributed to numerous well-arranged intermolecular C-H⋯π interactions between the ligands. Moreover, the electrocatalytic CO2 reduction properties suggested that internal PO4 templates and external naphthyl groups could promote an increase in C2 products (C2H4 and C2H5OH). Our research provides new insight into the design and synthesis of multifunctional copper(i) clusters, and highlights the significance of atomic-level comparative studies of structure-property relationships.

4.
Toxicol Rep ; 11: 212-215, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37727219

ABSTRACT

Background: The agricultural industry has experienced beneficial outcomes by implementing contemporary synthetic pesticides, specifically, the mixture of acetamiprid and pyridaben. However, concerns regarding public health have arisen due to the increased number of suicides caused by insecticide poisoning. Nevertheless, limited reports of human exposure to these pesticides have reported various adverse clinical effects. In this study, we present the case of an individual who consumed the acetamiprid and pyridaben mixture for suicidal purposes, and subsequently developed central nervous system depression, hyperlactacidemia, and metabolic acid poisoning, which thus required clinical management. Case report: A 74-year-old woman was transported to our hospital after ingesting a combination of 30 mL of acetamiprid 5 % and pyridaben 5 %. The patient displayed nausea and vomiting symptoms, followed by confusion. An arterial blood gas analysis revealed metabolic acidosis and hyperlactacidemia. The patient was carefully monitored for vital signs and treated with gastric lavage, purgation, and proton pump inhibitors to reduce gastric acid, blood volume, and electrolyte resuscitation. In addition, the patient received 24 h of hemoperfusion (HP) and continuous renal replacement therapy (CRRT). As a result of these interventions, the patient had a speedy recovery and was discharged 10 days later. Conclusion: This case report provided the details of a rare instance of acute poisoning in humans resulting from exposure to newer synthetic pesticides, specifically acetamiprid and pyridaben. The report described the clinical manifestations and effective supportive therapy management. Future clinicians may find the results of this report valuable for identifying clinical symptoms and treating acute poisoning caused by newer synthetic pesticides.

5.
Chem Asian J ; 18(22): e202300844, 2023 Nov 16.
Article in English | MEDLINE | ID: mdl-37753735

ABSTRACT

Metal clusters have become increasingly important in various applications, with ligands playing a crucial role in their construction. In this study, we synthesized a bimetallic cluster, Ag6 Cu8 (C=CAr)14 (DPPB)2 (Ag6 Cu8 ), using a rigid acetylene ligand, 3,5-bis(trifluoromethyl)phenylacetylide. Through single-crystal structure characterization, we discovered that the butterfly-shaped Ag2 Cu2 motifs were subject to distortion due to steric hindrance imposed by the rigid ligand. These motifs assembled together through shared vertices and edges. Mass spectrometry analysis revealed that the primary fragments detected during electrospray ionization (ESI) testing corresponded to the Ag2 Cu2 motifs. Furthermore, we conducted a comprehensive investigation of the cluster's solution properties employing 31 P NMR, UV-vis absorption, and photoluminescent measurements. In contrast to previously reported Ag/Cu bimetallic clusters protected by flexible ligands, Ag6 Cu8 protected by rigid ligands exhibited intriguing room temperature fluorescence properties alongside excellent thermal stability. DFT calculations on Ag6 Cu8 and Ag6 Cu8 with the rigid aromatic ring removed revealed that the presence of the rigid aromatic ring can lower the electronic energy levels of the cluster, and reduce the energy gap from 4.05 eV to 3.45 eV. Moreover, the rigid ligand further suppressed the non-radiative transition process, leading to room temperature fluorescence emission.

6.
Adv Mater ; 35(51): e2303384, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37572021

ABSTRACT

Upscalable printing of high-performance and stable perovskite solar cells (PSCs) is highly desired for commercialization. However, the efficiencies of printed PSCs lag behind those of their lab-scale spin-coated counterparts owing to the lack of systematic understanding and control over perovskite crystallization dynamics. Here, the controlled crystallization dynamics achieved using an additive 1-butylpyridine tetrafluoroborate (BPyBF4 ) for high-quality ambient printed α-formamidinium lead triiodide (FAPbI3 ) perovskite films are reported. Using in situ grazing-incidence wide-angle X-ray scattering and optical diagnostics, the spontaneous formation of α-FAPbI3 from precursors during printing without the involvement of  Î´-FAPbI3 is demonstrated. The addition of BPyBF4 delays the crystallization onset of α-FAPbI3 , enhances the conversion from sol-gel to perovskite, and reduces stacking defects during printing. Therefore, the altered crystallization results in fewer voids, larger grains, and less trap-induced recombination loss within printed films. The printed PSCs yield high power conversion efficiencies of 23.50% and 21.60% for a 0.09 cm-2 area device and a 5 cm × 5 cm-area module, respectively. Improved device stability is further demonstrated, i.e., approximately 94% of the initial efficiency is retained for over 2400 h under ambient conditions without encapsulation. This study provides an effective crystallization control method for the ambient printing manufacture of large-area high-performance PSCs.

7.
BMC Pulm Med ; 23(1): 102, 2023 Mar 28.
Article in English | MEDLINE | ID: mdl-36978069

ABSTRACT

PURPOSE: The clinical characteristics of Klebsiella pneumoniae (KP) pneumonia and KP bloodstream infection (KP-BSI) are often reported, while the risk factors for KP pneumonia developing into secondary KP-BSI (KP-pneumonia/KP-BSI) are largely unknown. Therefore, this study attempted to investigate the clinical characteristics, risk factors and outcomes of KP-pneumonia/KP-BSI. METHODS: A retrospective observational study was conducted at a tertiary hospital between January 1, 2018, and December 31, 2020. The patients were divided into groups of KP pneumonia alone and KP pneumonia/KP-BSI, and the clinical information were collected from medical records electronic system. RESULTS: A total of 409 patients were finally recruited. According to the multivariate logistic regression analysis, male sex (adjusted odds ratio [aOR] 3.7; 95% CI, 1.44-9.5), immunosuppression (aOR, 13.52; 95% CI, 2.53,72.22), APACHE II score higher than 21 (aOR, 3.39; 95% CI, 1.41-8.12), serum procalcitonin (PCT) levels above 1.8 ng/ml (aOR, 6.37; 95% CI, 2.67-15.27), ICU stay of more than 2.5 days before pneumonia onset (aOR, 1.09; 95% CI, 1.02,1.17), mechanical ventilation (aOR, 4.96; 95% CI, 1.2,20.5), Klebsiella pneumoniae isolates producing extended spectrum ß-lactamase (ESBL-positive KP) (aOR, 12.93; 95% CI, 5.26-31.76), and inappropriate antibacterial therapy (aOR, 12.38; 95% CI, 5.36-28.58) were independent factors of KP pneumonia/KP BSI. In comparison with the patients with KP pneumonia alone, the patients with KP pneumonia/KP BSI showed an almost 3 times higher incidence of septic shock (64.4% vs. 20.1%, p < 0.01), a longer duration of mechanical ventilation, and longer lengths of ICU stay and total hospital stay (median days, 15 vs. 4,19 vs. 6, 34 vs. 17, respectively, both p < 0.01). Additionally, the overall in-hospital crude mortality rate in the patients with KP-pneumonia/KP-BSI was more than two times higher than that in those with KP pneumonia alone (61.5% vs. 27.4%, p < 0.01). CONCLUSION: Factors including male sex, immunosuppression, APACHE II score higher than 21, serum PCT levels above 1.8 ng/ml, ICU stay of more than 2.5 days before pneumonia onset, mechanical ventilation, ESBL-positive KP, and inappropriate antibacterial therapy are independent risk factors for KP pneumonia/KP-BSI. Of note, the outcomes in patients with KP pneumonia worsen once they develop secondary KP-BSI, which merits more attention.


Subject(s)
Bacteremia , Coinfection , Klebsiella Infections , Sepsis , Humans , Male , Klebsiella pneumoniae , Klebsiella , Klebsiella Infections/epidemiology , Klebsiella Infections/microbiology , Bacteremia/drug therapy , Risk Factors , Anti-Bacterial Agents/therapeutic use , Retrospective Studies , Coinfection/drug therapy
8.
Nat Commun ; 14(1): 839, 2023 Feb 15.
Article in English | MEDLINE | ID: mdl-36792606

ABSTRACT

Even though the perovskite solar cell has been so popular for its skyrocketing power conversion efficiency, its further development is still roadblocked by its overall performance, in particular long-term stability, large-area fabrication and stable module efficiency. In essence, the soft component and ionic-electronic nature of metal halide perovskites usually chaperonage large number of anion vacancy defects that act as recombination centers to decrease both the photovoltaic efficiency and operational stability. Herein, we report a one-stone-for-two-birds strategy in which both anion-fixation and associated undercoordinated-Pb passivation are in situ achieved during crystallization by using a single amidino-based ligand, namely 3-amidinopyridine, for metal-halide perovskite to overcome above challenges. The resultant devices attain a power conversion efficiency as high as 25.3% (certified at 24.8%) with substantially improved stability. Moreover, the device without encapsulation retained 92% of its initial efficiency after 5000 h exposure in ambient and the device with encapsulation retained 95% of its initial efficiency after >500 h working at the maximum power point under continuous light irradiation in ambient. It is expected this one-stone-for-two-birds strategy will benefit large-area fabrication that desires for simplicity.

9.
Insights Imaging ; 13(1): 179, 2022 Nov 22.
Article in English | MEDLINE | ID: mdl-36417020

ABSTRACT

OBJECTIVE: Accurate preoperative assessment of extramural vascular invasion (EMVI) is critical for the treatment and prognosis of rectal cancer. The aim of our research was to develop an assessment model by texture analysis for preoperative prediction of EMVI. MATERIALS AND METHODS: This study enrolled 44 rectal patients as train cohort, 7 patients as validation cohort and 18 patients as test cohort. A total of 236 texture features from DCE MR imaging quantitative parameters were extracted for each patient (59 features of Ktrans, Kep, Ve and Vp), and key features were selected by least absolute shrinkage and selection operator regression (LASSO). Finally, clinical independent risk factors, conventional MRI assessment, and T-score were incorporated to construct an assessment model using multivariable logistic regression. RESULTS: The T-score calculated using the 4 selected key features were significantly correlated with EMVI (p < 0.010). The area under the receiver operating characteristic curve (AUC) was 0.797 for discriminating between EMVI-positive and EMVI-negative patients with a sensitivity of 88.2% and specificity of 70.4%. The conventional MRI assessment of EMVI had a sensitivity of 23.53% and a specificity of 96.30%. The assessment model showed a greatly improved performance with an AUC of 0.954 (sensitivity, 88.2%; specificity, 92.6%) in train cohort, 0.833 (sensitivity, 66.7%; specificity, 100%) in validation cohort and 0.877 in test cohort, respectively. CONCLUSIONS: The assessment model showed an excellent performance in preoperative assessment of EMVI. It demonstrates strong potential for improving the accuracy of EMVI assessment and provide a reliable basis for individualized treatment decisions.

10.
Dalton Trans ; 51(38): 14557-14562, 2022 Oct 04.
Article in English | MEDLINE | ID: mdl-36074660

ABSTRACT

Under the guidance of anion templates V10O286- and SO42-, the novelty of cluster assembly can be increased by using different carboxylate ligands. Herein, the synthesis, crystal structure and electrochemical properties of three anion-templated silver thiolated clusters are reported, namely V10O28@Ag46(iPrS)28(CF3CO2)12(DMF)2 (1), V10O28@Ag46(iPrS)30(CF3CO2)8(PhCO2)2(DMF)4 (2), and [SO4@Ag20(iPrS)10(PTA)3(HPTA)2]n (3, H2PTA = phthalic acid). Single-crystal X-ray diffraction analysis showed that 1 and 2 are discrete clusters V10O28@Ag46. The addition of PhCO2H in the second step of 1 leads to obtaining 2 with different organic shells. If the addition of H2PTA is made, 3 with a three-dimensional (3D) structure containing the SO42- template can be obtained. Both V10O286- and SO42- templates were generated in situ under solvothermal conditions. This work is the first where heterogeneous silver clusters containing the V10O286- anion template protected by an isopropyl thiolate ligand and a Ag20 cluster with a 3D structure are obtained. The assembly process influenced by carboxylic acid deserves to be continuously explored in the future.

11.
Adv Mater ; 34(10): e2106750, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34964993

ABSTRACT

All-inorganic cesium lead triiodide (CsPbI3 ) perovskite is well known for its unparalleled stability at high temperatures up to 500 °C and under oxidative chemical stresses. However, upscaling solar cells via ambient printing suffers from imperfect crystal quality and defects caused by uncontrollable crystallization. Here, the incorporation of a low concentration of novel ionic liquid is reported as being promising for managing defects in CsPbI3 films, interfacial energy alignment, and device stability of solar cells fabricated via ambient blade-coating. Both theoretical simulations and experimental measurements reveal that the ionic liquid successfully regulates the perovskite thin-film growth to decrease perovskite grain boundaries, strongly coordinates with the undercoordinated Pb2+ to passivate iodide vacancy defects, aligns the interface to decrease the energy barrier at the electron-transporting layer, and relaxes the lattice strain to promote phase stability. Consequently, ambient printed CsPbI3 solar cells with power conversion efficiency as high as 20.01% under 1 sun illumination (100 mW cm-2 ) and 37.24% under indoor light illumination (1000 lux, 365 µW cm-2 ) are achieved; both are the highest for printed all-inorganic cells for corresponding applications. Furthermore, the bare cells show an impressive long-term ambient stability with only ≈5% PCE degradation after 1000 h aging under ambient conditions.

12.
J Am Chem Soc ; 143(31): 12063-12073, 2021 Aug 11.
Article in English | MEDLINE | ID: mdl-34342223

ABSTRACT

Two-dimensional (2D) halide perovskites have several distinct structural classes and exhibit great tunability, stability, and high potential for photovoltaic applications. Here, we report a new series of hybrid 2D perovskites in the Dion-Jacobson (DJ) class based on aromatic m-phenylenediammonium (mPDA) dications. The crystal structures of the DJ perovskite materials (mPDA)MAn-1PbnI3n+1 (n = 1-3) were solved and refined using single-crystal X-ray crystallography. The results indicate a short I···I interlayer distance of 4.00-4.04 Å for the (mPDA)MAn-1PbnI3n+1 (n = 2 and 3) structures, which is the shortest among DJ perovskites. However, Pb-I-Pb angles are as small as 158-160°, reflecting the large distortion of the inorganic framework, which results in larger band gaps for these materials than those in other DJ analogues. Density functional theory calculations suggest appreciable dispersion in the stacking direction, unlike the band structures of the Ruddlesden-Popper phases, which exhibit flat bands along the stacking direction. This is a consequence of the short interlayer I···I distances that can lead to interlayer electronic coupling across the layers. The solution-deposited films (nominal (mPDA)MAn-1PbnI3n+1 compositions of n = 1-6) reveal improved surface coverage with increasing nominal n value with the higher n films being composed of a mixture of n = 1 and bulk three-dimensional MAPbI3 perovskites. The films made from solutions of these materials behave differently from those of other 2D iodide perovskites, and their solar cells have a mixture of n = 1 DJ and MAPbI3 as light-absorbing semiconductors.

13.
Inorg Chem ; 60(17): 13493-13499, 2021 Sep 06.
Article in English | MEDLINE | ID: mdl-34410688

ABSTRACT

Four copper(I) alkynyl complexes incorporating phosphate ligands, namely, [Cu16(tBuC≡C)12(PhOPO3)2]n (1; PhOPO3 = phenyl phosphate), [Cu16(tBuC≡C)12(1-NaphOPO3)2]n (2; 1-NaphOPO3 = 1-naphthyl phosphate), [VO4@Cu25(tBuC≡C)19(1-NaphOPO3)](PF6)0.5(F)0.5 (3), and [PO4@Cu25(tBuC≡C)19(1-NaphOPO3)](PF6)0.5(F)0.5 (4), were solvothermally synthesized and well-characterized by IR spectroscopy, powder X-ray diffraction, and single-crystal X-ray diffraction. Single-crystal X-ray analysis revealed that the Cu16 cluster-based coordination chain polymers 1 and 2 are formed by assembly during crystallization, while 3 and 4 contain high-nuclearity copper(I) composite clusters enclosing orthovanadate and phosphate template ions, respectively, that are supported by ROPO32- ligands. Complexes 1-4 exhibit crystallization-induced emission enhancement. Their crystalline state shows strong luminescence, in striking contrast to the weak emission of the amorphous state and solution phase. A detailed investigation of the crystal structure suggests that well-arranged C-H···π and π···π interactions between the ligands are the major factors for this enhanced emission. Clusters 3 and 4 also exhibit photocurrent responses upon visible-light illumination.

14.
Adv Mater ; 33(27): e2100770, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34057256

ABSTRACT

Perovskite solar cells exhibit not only high efficiency under full AM1.5 sunlight, but also have great potential for applications in low-light environments, such as indoors, cloudy conditions, early morning, late evening, etc. Unfortunately, their performance still suffers from severe trap-induced nonradiative recombination, particularly under low-light conditions. Here, a holistic passivation strategy is developed to reduce traps both on the surface and in the bulk of micrometer-thick perovskite film, leading to a record efficiency of 40.1% under 301.6 µW cm-2 warm light-emitting diode (LED) light for low-light solar-cell applications. The involvement of guanidinium into the perovskite bulk film and 2-(4-methoxyphenyl)ethylamine hydrobromide (CH3 O-PEABr) passivation on the perovskite surface synergistically suppresses the trap states. The charge carrier lifetimes of the perovskite film increase by tenfold and fivefold to 981 ns and 8.02 µs at the crystal surface and in its bulk, respectively. The decreased nonradiative recombination loss translates to a high open-circuit voltage (Voc ) of 1.00 V, a high short-circuit current (Jsc ) of 152.10 µA cm-2 , and a fill factor (FF) of 79.52%. Note that this performance also stands as the highest among all photovoltaics measured under indoor light illumination. This work of trap passivation for micrometer-thick perovskite film paves a way for high-performance, self-powered IoT devices.

15.
Adv Sci (Weinh) ; 8(13): e2001433, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34032005

ABSTRACT

New structural type of 2D AA'n -1 Mn X3 n +1 type halide perovskites stabilized by symmetric diammonium cations has attracted research attention recently due to the short interlayer distance and better charge-transport for high-performance solar cells (PSCs). However, the distribution control of quantum wells (QWs) and its influence on optoelectronic properties are largely underexplored. Here effective phase-alignment is reported through dynamical control of film formation to improve charge transfer between quantum wells (QWs) for 2D perovskite (BDA)(MA)n -1 Pbn I3 n +1 (BDA = 1,4-butanediamine, 〈n〉 = 4) film. The in situ optical spectra reveal a significantly prolonged crystallization window during the perovskite deposition via additive strategy. It is found that finer thickness gradient by n values in the direction orthogonal to the substrate leads to more efficient charge transport between QWs and suppressed charge recombination in the additive-treated film. As a result, a power conversion efficiency of 14.4% is achieved, which is not only 21% higher than the control one without additive treatment, but also one of the high efficiencies of the low-n (n ≤ 4) AA'n -1 Mn X3 n +1 PSCs. Furthermore, the bare device retains 92% of its initial PCE without any encapsulation after ambient exposure for 1200 h.

16.
Inorg Chem ; 60(9): 6276-6282, 2021 May 03.
Article in English | MEDLINE | ID: mdl-33872497

ABSTRACT

A zwitterionic ligand 3-(triethylammonio)propyne (TAP) has been employed to construct nine silver ethynide compounds for the first time. Single-crystal X-ray analyses reveal that compounds 1 and 2 are silver ethynide assemblies based on the Ag3 subunits and clusters 3-8 are small discrete clusters of Ag3, Ag6, Ag8, and Ag12, respectively, ligated by the bulky TAP ligand with different auxiliary ligands. In addition, upon acquiring the tripod-like tBuPO32-, a unprecedented 80 nuclei silver ethynide cluster was isolated and determined to be [(CF3CO2)5@Ag80(TAP)14(tBuPO3)16(CF3CO2)24]19+ by crystallography and thermogravimetric analysis. The C1 symmetry of Ag80 was deconstructed to be two [Ag40(TAP)7(tBuPO3)8(CF3CO2)12]12+ secondary building subunits arranged in a cross way, with five CF3CO2- trapped in the center. These results highlight that the elaborate selection of ethynide ligands is of great importance in the synthesis of novel silver ethynide clusters.

17.
Research (Wash D C) ; 2021: 9671892, 2021.
Article in English | MEDLINE | ID: mdl-33681813

ABSTRACT

Eco-friendly printing is important for mass manufacturing of thin-film photovoltaic (PV) devices to preserve human safety and the environment and to reduce energy consumption and capital expense. However, it is challenging for perovskite PVs due to the lack of eco-friendly solvents for ambient fast printing. In this study, we demonstrate for the first time an eco-friendly printing concept for high-performance perovskite solar cells. Both the perovskite and charge transport layers were fabricated from eco-friendly solvents via scalable fast blade coating under ambient conditions. The perovskite dynamic crystallization during blade coating investigated using in situ grazing incidence wide-angle X-ray scattering (GIWAXS) reveals a long sol-gel window prior to phase transformation and a strong interaction between the precursors and the eco-friendly solvents. The insights enable the achievement of high quality coatings for both the perovskite and charge transport layers by controlling film formation during scalable coating. The excellent optoelectronic properties of these coatings translate to a power conversion efficiency of 18.26% for eco-friendly printed solar cells, which is on par with the conventional devices fabricated via spin coating from toxic solvents under inert atmosphere. The eco-friendly printing paradigm presented in this work paves the way for future green and high-throughput fabrication on an industrial scale for perovskite PVs.

18.
Adv Mater ; 32(40): e2001243, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32864773

ABSTRACT

All-inorganic CsPbI3 holds promise for efficient tandem solar cells, but reported fabrication techniques are not transferrable to scalable manufacturing methods. Herein, printable CsPbI3 solar cells are reported, in which the charge transporting layers and photoactive layer are deposited by fast blade-coating at a low temperature (≤100 °C) in ambient conditions. High-quality CsPbI3 films are grown via introducing a low concentration of the multifunctional molecular additive Zn(C6 F5 )2 , which reconciles the conflict between air-flow-assisted fast drying and low-quality film including energy misalignment and trap formation. Material analysis reveals a preferential accumulation of the additive close to the perovskite/SnO2 interface and strong chemisorption on the perovskite surface, which leads to the formation of energy gradients and suppressed trap formation within the perovskite film, as well as a 150 meV improvement of the energetic alignment at the perovskite/SnO2 interface. The combined benefits translate into significant enhancement of the power conversion efficiency to 19% for printable solar cells. The devices without encapsulation degrade only by ≈2% after 700 h in air conditions.

19.
ACS Appl Mater Interfaces ; 12(39): 43885-43891, 2020 Sep 30.
Article in English | MEDLINE | ID: mdl-32869968

ABSTRACT

Guanidinium (GA) has been widely used as an additive in solar cells for enhanced performance. However, the size of the guanidinium cation is too large to be incorporated in the cage of the perovskite structure. Instead, GA forms a variety of structures with lead iodide, where its role in the perovskite crystal as well as solar cell devices is unclear. In this study, we demonstrate that GA can be incorporated into the structure of MAPbI3 as (GA)x(MA)1-xPbI3. From single-crystal X-ray crystallographic refinement, we observe lattice expansion and Pb-I bond elongation with GA incorporation similar to exerting "negative pressure", which weakens orbital overlap and widens the band gap from 1.49 to 1.53 eV. We find that the highest percentage of GA that can be incorporated into the 3D MAPbI3 structure is 5.26%, as confirmed by nuclear magnetic resonance. The alloyed (GA)x(MA)1-xPbI3 exhibits increased PL lifetimes from 154.4 to 266.3 ns after GA incorporation while the Voc of (GA)x(MA)1-xPbI3 devices enlarges from 1.05 to 1.11 V. High efficiencies in solar cell devices up to 20.38% with a Jsc of 23.55 mA cm-2, Voc of 1.11 V, and FF of 0.78 have been achieved, with stable photovoltaic performance for 900 h in air.

20.
Heart Fail Rev ; 25(2): 331-341, 2020 03.
Article in English | MEDLINE | ID: mdl-31641977

ABSTRACT

Changes of serum galectin-3 have been associated with the pathogenesis of many cardiovascular diseases. The aim of the study was to evaluate the prognostic role of serum galectin-3 in patients with acute heart failure (AHF) in a meta-analysis. Follow-up studies evaluating the association between serum galectin-3 on admission and clinical outcomes in AHF patients were identified via search of PubMed and Embase databases. A random effects or a fixed effects model was applied to pool the results depending on the heterogeneity. Subgroup analysis was used to evaluate the influences of study characteristics on the outcomes. Overall, 7057 AHF patients from eighteen follow-up studies were included. Higher serum galectin-3 was associated with higher risks of all-cause mortality (adjusted risk ratio [RR], 1.58; p < 0.001), mortality/HF rehospitalization (RR, 1.68; p < 0.001), and cardiovascular mortality (RR, 1.29; p = 0.04), but not HF rehospitalization (RR, 1.24; p = 0.25) in AHF patients. Subgroup analyses showed that study characteristics including study design, sample size, age, gender, left ventricular ejection fraction, galectin-3 variable type, follow-up duration, and adjustment of type B natriuretic peptide did not significantly impact the results. Significant heterogeneities were detected for the outcomes of all-cause mortality and mortality/HF rehospitalization. However, trim-and-fill analyses by including the imputed studies to generate symmetrical funnel plots showed similar significant meta-analysis results. These results suggested that higher serum galectin-3 may be associated with poor prognosis in AHF patients. Further studies are needed to determine the mechanisms underlying the potential prognostic role of galectin-3 in AHF.


Subject(s)
Galectins/blood , Heart Failure/blood , Stroke Volume/physiology , Acute Disease , Biomarkers/blood , Blood Proteins , Heart Failure/physiopathology , Humans , Prognosis
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