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Metal halide perovskite ferroelectrics combining spontaneous polarization and excellent semiconducting properties is an ideal platform for enabling self-driven X-ray detection, however, achievements to date have been only based on uniaxiality, which increases the complexity of device fabrication. Multi-axial ferroelectric materials have multiple equivalent polarization directions, making them potentially amenable to multi-axial self-driven X-ray detection, but the report on these types of materials is still a huge blank. Herein, a high-quality (BA)2(EA)2Pb3I10 (1) biaxial ferroelectric single crystal was successfully grown, which exhibited significant spontaneous polarization along the c-axis and b-axis. Under X-ray irradiation, bulk photovoltaic effect (BPVE) was exhibited along both the c-axis and b-axis, with open circuit voltages (Voc) of 0.23 V and 0.22 V, respectively. Then, the BPVE revealed along the inversion of polarized direction with the polarized electric fields. Intriguingly, due to the BPVE of 1, 1 achieved multi-axial self-driven X-ray detection for the first time (c-axis and b-axis) with relatively high sensitivities and ultralow detection limits (17.2 nGyair s-1 and 19.4 nGyair s-1, respectively). This work provides a reference for the subsequent use of multi-axial ferroelectricity for multi-axial self-driven optoelectronic detection.
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2D organic-inorganic hybrid perovskites (OIHPs) have shown great promise in direct X-ray detection. The development of high-performance passive X-ray detectors in 2D OIHPs calls for an increase in material density while maintaining structural polarity, which is becoming quite challenging. Here, a high-density, polar 2D alternating-cation-intercalated (ACI) perovskite, (4-AP)Cs2Pb2I8 (B, 4-AP = 4-amidinopyridinium), capable of addressing this problem is successfully constructed by introducing heavy Cs+ into the interlayer space of an aromatic Dion-Jacobson (DJ) perovskite (4-AP)PbI4 (A). Through such a DJ-to-ACI design, the newly developed 2D OIHP B not only significantly increases its density to 4.23 g cm-3 (even higher than that of 3D MAPbI3) but also crystallizes in a polar space group (Ama2), which further leads to enhanced X-ray attenuation and an obvious polar photovoltage (1.1 V) under X-ray irradiation. As a result, X-ray detectors fabricated by high-quality single crystals of B exhibit excellent and stable detection performance under self-powered mode with a high sensitivity of 107 µC Gy-1 cm-2 and a low detection limit of 289 nGy s-1. This work provides implications for the future exploration and regulation of novel ACI OIHPs for high-performance photoelectronic devices.
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The aim of this study was to develop and fully validate a sensitive and rapid ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method for simultaneous quantification of pristinamycin â A (Pâ A) and pristinamycin â ¡A (Pâ ¡A) in plasma of beagle dogs after oral administration of pristinamycin tablets. Pâ A, Pâ ¡A and quinupristin (internal standard, IS) were separated on an Agilent Eclipse Plus C18 column (2.1â¯mm × 100â¯mm, 3.5 µm particle size) by using gradient elution consisting of methanol and water (0.1â¯% formic acid) at a flow rate of 0.4â¯mL/min in 4.0â¯min. Multiple reaction monitoring (MRM) mode was performed to quantify data under monitoring precursor-product ion transitions of m/z 867.6â134.1, 548.4â287.1 and 1022.7â133.9 for Pâ A, Pâ ¡A and IS at positive ion mode, respectively. The method was developed at linearity ranging from 1.0 to 1000â¯ng/mL for all analytes.The accuracy of Pâ A and Pâ ¡A was observed to range between -10.6â¯% and 7.1â¯%, while the precision was found to be within 8.9â¯%. No significant matrix effect was observed. Pâ A and Pâ ¡A demonstrated stability during sample storage, preparation and analytic procedures. Furthermore, this method was successfully applied in the investigation of the pharmacokinetic profile of Pâ A and Pâ ¡A in beagle dogs after oral administration of pristinamycin tablets (75â¯mg for Pâ A and 175â¯mg for Pâ ¡A). The biological half-life (t1/2) was determined to be 1.75 ± 0.07â¯h and 1.44 ± 0.31â¯h for Pâ A and Pâ ¡A, respectively. The areas under curves (AUC0-t) of Pâ A and Pâ ¡A were 80.7 ± 24.6 and 230 ± 94.8⯵g/L·h, respectively.
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Photopyroelectric-based circularly polarized light (CPL) detection, coupling the pyro-phototronic effect and chiroptical phenomena, has provided a promising platform for high-performance CPL detectors. However, as a novel detection strategy, photopyroelectric-based CPL detection is currently restricted by the short-wave optical response, underscoring the urgent need to extend its response range. Herein, visible-to-near-infrared CPL detection induced by the pyro-phototronic effect is first realized in chiral-polar perovskites. Specifically, chiral-polar multilayered perovskites (S-BPEA)2FAPb2I7 (1-S, S-BPEA = (S)-1-4-Bromophenylethylammonium, FA = formamidinium) with spontaneous polarization shows intrinsic pyroelectric and photopyroelectric performance. Strikingly, combining its merits of the pyro-phototronic effect and intrinsic wide-spectrum spin-selective effect, chiral multilayered 1-S presents efficient photopyroelectric-based broadband CPL detection performance spanning 405-785 nm. This research first realizes photopyroelectric-based infrared CPL detection and also sheds light on developing high-performance broadband CPL detectors based on the pyro-phototronic effect in the fields of optics, optoelectronics, and spintronics.
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Metal halide perovskites have outperformed conventional inorganic semiconductors in direct X-ray detection due to their ease of synthesis and intriguing photoelectric properties. However, the operational instability caused by severe ion migration under a high external electric field is still a big concern for the practical application of perovskite detectors. Here, we report a 2D (BPEA)2PbI4 (BPEA = R-1-(4-bromophenyl)ethylammonium) perovskite with Br-substituted aromatic spacer capable of introducing abundant interactions, e.g., the molecular electrostatic forces between Br atoms and aromatic rings and halogen bonds of Br-I, in the interlayer space, which effectively suppresses ion migration and thus enables superior operational stability. Constructing direct X-ray detectors based on high-quality single crystals of (BPEA)2PbI4 results in a high sensitivity of 1,003 µC Gy-1 cm-2, a low detection limit of 366 nGy s-1, and an ultralow baseline drift of 3.48 × 10-8 nA cm-1 s-1 V-1 at 80 V bias. More strikingly, it also exhibits exceptional operational stability under high flux, long-time X-ray irradiation, and large working voltage. This work shows an integration of multiple interlayer interactions to stabilize perovskite X-ray detectors, providing new insights into the future design of perovskite optoelectronic devices toward practical application.
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(1) Background: The research group has developed a new small molecule, 6-Isopropyldithio-2'-deoxyguanosine analogs-YLS004, which has been shown to be the most sensitive in acute T-lymphoblastic leukemia cells. Moreover, it was found that the structure of Nelarabine, a drug used to treat acute T-lymphoblastic leukemia, is highly similar to that of YLS004. Consequently, the structure of YLS004 was altered to produce a new small molecule inhibitor for this study, named YLS010. (2) Results: YLS010 has exhibited potent anti-tumor effects by inducing cell apoptosis and ferroptosis. A dose gradient was designed for in vivo experiments based on tentative estimates of the toxicity dose using acute toxicity in mice and long-term toxicity in rats. The study found that YLS010 at a dose of 8 mg/kg prolonged the survival of late-stage acute T-lymphoblastic leukemia mice in the mouse model study. (3) Conclusions: YLS010 has demonstrated specific killing effects against acute T-lymphoblastic leukemia both in vivo and in vitro. Preclinical studies of YLS010 offer a new opportunity for the treatment of patients with acute T-lymphoblastic leukemia in clinical settings.
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The low-toxic and environmentally friendly 2D lead-free perovskite has made significant progress in the exploration of "green" X-ray detectors. However, the gap in detection performance between them and their lead-based analogues remains a matter of concern that cannot be ignored. To reduce this gap, shortening the interlayer spacing to accelerate the migration and collection of X-ray carriers is a promising strategy. Herein, a Dion-Jacobson (DJ) lead-free double perovskite (4-AP)2AgBiBr8 (1, 4-AP = 4-amidinopyridine) with an ultra-narrow interlayer spacing of 3.0 Å, is constructed by utilizing π-conjugated aromatic spacers. Strikingly, the subsequent enhanced carrier transport and increased crystal density lead to X-ray detectors based on bulk single crystals of 1 with a high sensitivity of 1117.3 µC Gy-1 cm-2, superior to the vast majority of similar double perovskites. In particular, the tight connection of the inorganic layers by the divalent cations enhances structural rigidity and stability, further endowing 1 detector with ultralow dark current drift (3.06 × 10-8 nA cm-1 s-1 V-1, 80 V), excellent multiple cycles switching X-ray irradiation stability, as well as long-term environmental stability (maintains over 94% photoresponse after 90 days). This work brings lead-free double perovskites one step closer to realizing efficient practical green applications.
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Three-dimensional (3D) organic-inorganic hybrid perovskites (OIHPs) have achieved tremendous success in direct X-ray detection due to their high absorption coefficient and excellent carrier transport. However, owing to the centrosymmetry of classic 3D structures, these reported X-ray detectors mostly require external electrical fields to run, resulting in bulky overall circuitry, high energy consumption, and operational instability. Herein, we first report the unprecedented radiation photovoltage in 3D OIHP for efficient self-driven X-ray detection. Specifically, the 3D polar OIHP MhyPbBr3 (1, Mhy=methylhydrazine) shows an intrinsic radiation photovoltage (0.47â V) and large mobility-lifetime product (1.1×10-3 â cm2 V-1 ) under X-ray irradiation. Strikingly, these excellent physical characteristics endow 1 with sensitive self-driven X-ray detection performance, showing a considerable sensitivity of 220â µC Gy-1 cm-2 , which surpasses those of most self-driven X-ray detectors. This work first explores highly sensitive self-driven X-ray detection in 3D polar OIHPs, shedding light on future practical applications.
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Lead halide hybrid perovskites have made great progress in direct X-ray detection and broadband photodetection, but the existence of toxic Pb and the demand for external operating voltage have severely limited their further applications and operational stability improvements. Therefore, exploring "green" lead-free hybrid perovskite that can both achieve X-ray detection and broadband photodetection without external voltage is of great importance, but remains severely challenging. Herein, using centrosymmetric (BZA)3BiI6 (1, BZA = benzylamine) as a template, a pair of chiral-polar lead-free perovskites, (BZA)2(R/S-PPA)BiI6 (2-R/S, R/S-PPA = (R/S)-1-Phenylpropylamine) are successfully obtained by introducing chiral aryl cations of (R/S)-1-Phenylpropylamine. Compared to 1, chiral-polar 2-R presents a significant irradiation-responsive bulk photovoltaic effect (BPVE) with an open circuit photovoltage of 0.4 V, which enables it with self-powered X-ray, UV-vis-NIR broadband photodetection. Specifically, 2-R device exhibits an ultralow detection limit of 18.5 nGy s-1 and excellent operational stability. Furthermore, 2-R as the first lead-free perovskite achieves significant broad-spectrum (377-940 nm) photodetection via light-induced pyroelectric effect. This work sheds light on the rational crystal reconstruction engineering and design of "green" hybrid perovskite toward high-demanded self-powered radiation detection and broadband photodetection.
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2D multilayered organic-inorganic hybrid perovskites (OIHPs) have exhibited bright prospects for high-performance self-driven X-ray detection due to their strong radiation absorption and long carrier transport. However, as an effective tool for self-driven X-ray detection, radiation photovoltaics remain rare, and underdeveloped in multilayered OIHPs. Herein, chirality to induce radiation photovoltaics in 2D multilayered chiral OIHPs is first utilized for efficient self-driven X-ray detection. Specifically, under X-ray irradiation, a multilayered chiral-polar (S-BPEA)2FAPb2I7 (1-S, S-BPEA = (S)-1-4-Bromophenylethylammonium, FA = formamidinium) shows remarkable radiation photovoltaics of 0.85 V, which endows 1-S excellent self-driven X-ray detection performance with a considerable sensitivity of 87.8 µC Gyair -1 cm-2 and a detection limit low to 161 nGyair s-1. Moreover, the sensitivity is high up to 1985.9 µC Gyair -1 cm-2 under 80 V bias, higher than most those of 2D OIHPs. These results demonstrate that chirality-induced radiation photovoltaics is an efficient strategy for self-driven X-ray detection.
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Polar photovoltaic effect (PPE) has attracted great attention in regulating desired optoelectronic properties, which can be driven by order-disorder and displacive phase transitions. Bond-switching is also a feasible method to induce PPE, but such investigation is very rare. Lead-halide hybrid perovskite (LHHP) is an outstanding photodetection material; lead atoms possess rich coordination modes to provide possibilities to construct switchable bonds. Here, a unique perovskitizer NâPb bond-switching is disclosed to induce polar photovoltage in the emerging LHHP, PA2MHy2Pb3Br10 (1, PA = n-propylamine, MHy = methylhydrazine). Interestingly, the perovskitizer MHy+ provides 2s2 lone pair while the Pb atom affords empty d orbitals, which coordinate with each other to generate a flexible NâPb bond. Further, the introduction of NâPb bonds results in a high distortion of the PbBr6 octahedron to form local polarity and further orientation to induce spontaneous polarization. More importantly, such a flexible NâPb bond switching mechanism drives a notable PPE and controllable polarized photo-response, a polarization ratio up to 9.7 at the polar phase in striking contrast with the non-polar phase (1.03). The work provides the first demonstration of bond-switching to induce polar phase transition and polar photovoltage in the photoconductive hybrid perovskites for photoelectric applications.
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Circularly polarized light (CPL) detection has wide applications in many fields, where the anisotropy factor (gIph ) is an important indicator to characterize the CPL detection performance. So far, many materials with high gIph have been reported, however, the exploration of the regulation of gIph is still in its infancy. Herein, two novel alternating chiral-achiral cations intercalation-type chiral hybrid perovskites (CHPs), named (R/S-1-phenylpropylamine)(propylamine)PbBr4 (1-R/S), exhibit above room-temperature (RT) polar-phase transition, which greatly regulates the gIph value. The gIph of 1-R is 0.04 in high-temperature phase chiral non-polar (P21 21 21 ) by applying 5 V bias, interestingly, with the temperature decrease, the gIph value in low-temperature phase chiral polar (P21 ) gradually increases (0.22@360K, 0.40@340K, 0.47@320K), and finally reaches a maximum of 0.5 at RT. Such value is not only the highest among 2D CHPs to date, but presents a 12.5-fold amplification compared with 0.04. Further, this rare phenomenon should be attributed to the built-in electric field induced by the polar photovoltaic effect, which sheds light on further obtaining CHPs with large gIph .
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Chiral hybrid perovskites combine the advantages of chiral materials and halide perovskites, offering an ideal platform for the design of circularly polarized light (CPL) detectors. The pyro-phototronic effect, as a special mechanism of the photoexcited pyroelectric signal, can significantly improve the performance of photodetectors, whereas it remains a great challenge to achieve pyroelectricity-based CPL detection. In this work, the chiroptical phenomena and the pyro-phototronic effect are combined in chiral-polar perovskites to achieve unprecedented pyroelectric-based CPL detection. Two novel two-dimensional (2D) lead-free chiral-polar double perovskites, S/R-[(4-aminophenyl)ethylamine]2AgBiI8·0.5H2O, are successfully designed and synthesized by introducing chiral organic ligands into metal halide frameworks. Strikingly, the photoresponse is substantially boosted with the support of the pyro-phototronic effect, showing an increased pyro-phototronic current that is 40 times greater than the photovoltaic current. Furthermore, the pyroelectric-based detector possesses excellent CPL detection capacity to distinguish different polarization states of CPL photons, which achieve an impressive glph of up to 0.27 at zero bias. This study provides a brand new process for CPL detection by utilizing the pyro-phototronic effect in chiral-polar perovskites, which opens a new avenue for chiral materials in optoelectronic applications.
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The intrinsic integration of structural flexibility, chiroptical activity, and photoelectric properties endows the two-dimensional (2D) chiral hybrid perovskites (CHPs) with significant application potential in chiroptoelectronics and spintronics. However, the scarcity of suitable chiral organic ligands severely hinders their extensive construction, necessitating the development of new strategies for designing 2D CHPs. Herein, by exploiting a half substitution method, we created a pair of 2D CHPs with alternating cations in the interlayer space (ACI), (R/S-PPA)(PA)PbBr4 (2R/2S, PPA = 1-phenylpropylamine, PA = n-pentylamine), from the achiral Ruddlesden-Popper (RP) (PA)2PbBr4 (1). The successful chirality transfer induces 2R/2S to crystallize in the chiral P212121 space group and thus acquire appealing chiroptical activity. Consequently, the single-crystal devices of 2R exhibit good distinguishability to the left- and right-handed circularly polarized 405 nm lights with a photocurrent dissymmetric factor of 0.10 at 10 V bias. This work demonstrates an intriguing achiral RP to chiral ACI motif reconstruction in 2D halide hybrid perovskites, opening a door for expanding the family of 2D CHPs.
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Delivery of growth factors (GFs) is challenging for regulation of cell proliferation and differentiation due to their rapid inactivation under physiological conditions. Here, a bioactive polyelectrolyte multilayer (PEM) is engineered by the combination of thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) and glycosaminoglycans to be used as reservoir for GF storage. PNIPAM-grafted-chitosan (PChi) with two degrees of substitution (DS) are synthesized, namely LMW* (DS 0.14) and HMW (DS 0.03), by grafting low (2 kDa) and high (10 kDa) molecular weight of PNIPAM on the backbone of chitosan (Chi) to be employed as polycations to form PEM with the polyanion heparin (Hep) at pH 4. Subsequently, PEMs are chemically crosslinked to improve their stability at physiological pH 7.4. Resulting surface and mechanical properties indicate that PEM containing HMW is responsive to temperature at 20 °C and 37 °C, while LMW is not. More importantly, Hep as terminal layer combined with HMW allows not only a better retention of the adhesive protein vitronectin but also a sustained release of FGF-2 at 37 °C. With the synergistic effect of vitronectin and matrix-bound FGF-2, significant promotion on adhesion, proliferation, and migration of 3T3 mouse embryonic fibroblasts is achieved on HMW-containing PEM compared to Chi-containing PEM and exogenously added FGF-2. Thus, PEM containing PNIPAM in combination with bioactive glycosaminoglycans like Hep represents a versatile approach to fabricate a GF delivery system for efficient cell culture, which can be potentially served as cell culture substrate for production of (stem) cells and bioactive wound dressing for tissue regeneration.
Assuntos
Quitosana , Heparina , Animais , Camundongos , Heparina/farmacologia , Heparina/química , Quitosana/química , Quitosana/farmacologia , Fator 2 de Crescimento de Fibroblastos/farmacologia , Vitronectina/farmacologia , Adesão Celular , Fibroblastos , Glicosaminoglicanos/química , Glicosaminoglicanos/farmacologiaRESUMO
Chiral three-dimensional hybrid organic-inorganic perovskites (3D HOIPs) would show unique chiroptoelectronic performance due to the combination of chirality and 3D structure. However, the synthesis of 3D chiral HOIPs remains a significant challenge. Herein, we constructed a pair of unprecedented 3D chiral halide perovskitoids (R/S-BPEA)EA6 Pb4 Cl15 (1-R/S) (R/S-BPEA=(R/S)-1-4-Bromophenylethylammonium, EA=ethylammonium), in which the large chiral cations can be contained in the big "hollow" inorganic frameworks induced by mixing cations. Notably, 3D 1-R/S shows natural chiroptical activity, as evidenced by its significant mirror circular dichroism spectra and the ability to distinguish circularly polarized light. Moreover, based on the unique 3D structure, 1-S presents sensitive X-ray detection performance with a low detection limit of 398â nGyair s-1 , which is 14â times lower than the regular medical diagnosis of 5.5â µGyair s-1 . In this work, 3D chiral halide perovskitoids provide a new route to develop chiral material in spintronics and optoelectronics.
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Heterojunctions are a promising class of materials for high-efficiency bifunctional oxygen electrocatalysts in both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). However, the conventional theories fail to explain why many catalysts behave differently in ORR and OER, despite a reversible path (* O2 â* OOHâ* Oâ* OH). This study proposes the electron-/hole-rich catalytic center theory (e/h-CCT) to supplement the existing theories, it suggests that the Fermi level of catalysts determines the direction of electron transfer, which affects the direction of the oxidation/reduction reaction, and the density of states (DOS) near the Fermi level determines the accessibility for injecting electrons and holes. Additionally, heterojunctions with different Fermi levels form electron-/hole-rich catalytic centers near the Fermi levels to promote ORR/OER, respectively. To verify the universality of the e/h-CCT theory, this study reveals the randomly synthesized heterostructural Fe3 N-FeN0.0324 (Fex N@PC with DFT calculations and electrochemical tests. The results show that the heterostructural F3 N-FeN0.0324 facilitates the catalytic activities for ORR and OER simultaneously by forming an internal electron-/hole-rich interface. The rechargeable ZABs with Fex N@PC cathode display a high open circuit potential of 1.504 V, high power density of 223.67 mW cm-2 , high specific capacity of 766.20 mAh g-1 at 5 mA cm-2 , and excellent stability for over 300 h.
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Broadband photodetectors (PDs) with low detection limits hold significant importance to next-generation optoelectronic devices. However, simultaneously detecting broadband (i.e., X-ray to visible regimes) and weak lights in a single semiconducting material remains highly challenging. Here, by alloying iodine-substituted short-chain cations into the 3D FAPbI3 (FA = formamidine), a new 2D bilayered lead iodide hybrid perovskite, (2IPA)2 FAPb2 I7 (1, 2IPA = 2-iodopropylammonium), that enables addressing this challenge is reported. Such a 2D multilayered structure and lead iodide composition jointly endow 1 with a minimized dark current (6.04 pA), excellent electrical property, and narrow bandgap (2.03 eV), which further gives it great potential for detecting broadband weak lights. Consequently, its high-quality single crystal PDs exhibit remarkable photoresponses to weak ultraviolet-visible lights (377-637 nm) at several tens of nW cm-2 with high responsivities (>102 mA W-1 ) and significant detectivities (>1012 Jones). Moreover, 1 has an excellent X-ray detection performance with a high sensitivity of 438 µC Gy-1 cm-2 and an ultralow detection limit of 20 nGy s-1 . These exceptional attributes make 1 a promising material for broadband weak lights detection, which also sheds light on future explorations of high-performance PDs based on 2D hybrid perovskites.
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Chiral perovskites have been demonstrated as promising candidates for direct circularly polarized light (CPL) detection due to their intrinsic chirality and excellent charge transport ability. However, chiral perovskite-based CPL detectors with both high distinguishability of left- and right-handed optical signals and low detection limit remain unexplored. Here, a heterostructure, (R-MPA)2 MAPb2 I7 /Si (MPA = methylphenethylamine, MA = methylammonium) is constructed, to achieve high-sensitive and low-limit CPL detection. The heterostructures with high crystalline quality and sharp interface exhibit a strong built-in electric field and a suppressed dark current, not only improving the separation and transport of the photogenerated carriers but also laying a foundation for weak CPL signals detection. Consequently, the heterostructure-based CPL detector obtains a high anisotropy factor up to 0.34 with a remarkably low CPL detection limit of 890 nW cm-2 under the self-driven mode. As a pioneering study, this work paves the way for designing high-sensitive CPL detectors that simultaneously have great distinguishing capability and low detection limit of CPL.
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Indolizine-carbaldehydes with the easily modifiable carbaldehyde group are important synthetic targets as versatile precursors for distinct indolizines. However, the efficient one-pot construction of trisubstituted indolizine-2-carbaldehydes represents a long-standing challenge. Herein, we report an unprecedented recyclable stereoauxiliary aminocatalytic approach via aminosugars derived from biomass, which enable the efficient one-pot synthesis of desired trisubstituted indolizine-2-carbaldehydes via [3+2] annulations of acyl pyridines and α,ß-unsaturated aldehyde. Compared to the steric shielding effect from α-anomer, a stereoauxiliary effect favored by ß-anomer of D-glucosamine is supported by control experiments. Furthermore, polymeric chitosan containing predominantly ß-D-anhydroglucosamine units also shows excellent catalytic performance in aqueous solutions for the conversion of various substrates, large-scale synthesis and catalytic cycling experiments. Thus, our approach advances the existing methodologies by providing a rich library of indolizine-2-aldehydes. In addition, it delivers an efficient protocol for a set of late-stage diversification and targeted modifications of bioactive molecules or drugs, as showcased with 1,2,3-trisubstituted indolizine-2-carbaldehydes.