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1.
Small ; : e2402385, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38742952

RESUMO

Non-radiative recombination losses limit the property of perovskite solar cells (PSCs). Here, a synergistic strategy of SnSe2QDs doping into SnO2 and chlorhexidine acetate (CA) coating on the surface of perovskite is proposed. The introduction of 2D SnSe2QDs reduces the oxygen vacancy defects and increases the carrier mobility of SnO2. The optimized SnO2 as a buried interface obviously improves the crystallization quality of perovskite. The CA containing abundant active sites of ─NH2/─NH─, ─C═N, CO, ─Cl groups passivate the defects on the surface and grain boundary of perovskite. The alkyl chain of CA also improves the hydrophobicity of perovskite. Moreover, the synergism of SnSe2QDs and CA releases the residual stress and regulates the energy level arrangement at the top and bottom interface of perovskite. Benefiting from these advantages, the bulk and interface non-radiative recombination loss is greatly suppressed and thereby increases the carrier transport and extraction in devices. As a result, the best power conversion efficiency (PCE) of 23.41% for rigid PSCs and the best PCE of 21.84% for flexible PSCs are reached. The rigid PSC maintains 89% of initial efficiency after storing nitrogen for 3100 h. The flexible PSCs retain 87% of the initial PCE after 5000 bending cycles at a bending radius of 5 mm.

2.
ACS Appl Mater Interfaces ; 16(19): 25385-25392, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38690867

RESUMO

In the endeavor to develop advanced photodetectors (PDs) with superior performance, all-inorganic perovskites, recognized for their outstanding photoelectric properties, have emerged as highly promising materials. Due to their unique electronic structure and band characteristics, the majority of all-inorganic perovskite materials are not sensitive to near-infrared (NIR) light. Here, we demonstrate the fabrication of a high-performance broadband PD comprising CsPbBr3 perovskite NCs/Y6 planar heterojunctions. The incorporation of Y6 not only facilitates charge transfer from CsPbBr3 NCs to Y6 for enhancing photodetection performance under visible illumination but also broadens the absorption spectrum range of the whole device toward the NIR regime. As a result, the heterojunction PD exhibits a photo-to-dark-current ratio above 105, a dynamic range of 149.5 dB, and an impressive lowest detection limit of incident power density of 1.6 nW/cm2 under 505 nm illumination. In the NIR regime, where photon energy is below the bandgap of CsPbBr3, electron-hole pairs can still be produced in the Y6 layer even when illuminated at 1120 nm. Consequently, photodetection is uniquely possible in PDs that incorporate heterojunctions when the illumination wavelength is longer than 565 nm. At 850 nm, the heterojunction device is capable of detecting light with power densities as low as 1.3 µW/cm2 corresponding to a LDR of 99.8 dB. The exceptional performance is attributed to the creation of a heterojunction between CsPbBr3 NCs and Y6. These findings propose a novel approach for developing broadband PDs based on perovskite NC materials.

3.
ACS Appl Mater Interfaces ; 16(1): 655-668, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38134003

RESUMO

The two-step deposition method offers significant advantages in the production of high-performance planar perovskite solar cells (PSCs). Nevertheless, there are still numerous challenges in regulating perovskite crystallization during the two-step process. In this work, two-dimensional (2D) material antimonene quantum sheets (AMQSs) as an additive are introduced to regulate the crystallization process of perovskite. As a result, perovskite films with high crystalline quality and vertical growth orientation are obtained by AMQSs providing heterogeneous nucleation sites with the penetration of a mixture solution of AMQSs and FAI into the PbI2 layer. Also, the influence mechanism of AMQSs on the crystallization of perovskite film is analyzed in details. At the same time, due to the chemical interaction between antimonene and the uncoordinated Pb2+, the defects in the perovskite are efficiently passivated. In addition, the energy level at the perovskite/SnO2 interface becomes more matched, leading to improved charge transport and extraction with the incorporation of AMQSs. Benefiting from the versatile AMQSs, the power conversion efficiency (PCE) of PSCs made by PbI2 + FAI:AMQSs is improved from 20.65 to 22.31% with the vastly enhanced Jsc and Voc. The ambient and operational stability of the unencapsulated PSCs fabricated using the PbI2 + FAI:AMQSs method were significantly improved, retaining 80% of the original PCE after being stored in a dark environment at a relative humidity of 30-40% for 18 days and 83% of the original PCE following continuous AM 1.5G illumination for 200 h.

4.
Small ; : e2308364, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38054792

RESUMO

The power conversion efficiency (PCE) and stability of perovskite solar cells (PSCs) are significantly reduced by defect-induced charge non-radiative recombination. Also, unexpected residual strain in perovskite films leads to an unfavorable impact on the stability and efficiency of PSCs, notably flexible PSCs (f-PSCs). Considering these problems, a thorough and effective strategy is proposed by incorporating phytic acid (PA) into SnO2 as an electron transport layer (ETL). With the addition of PA, the Sn inherent dangling bonds are passivated effectively and thus enhance the conductivity and electron mobility of SnO2 ETL. Meanwhile, the crystallization quality of perovskite is increased largely. Therefore, the interface/bulk defects are reduced. Besides, the residual strain of perovskite film is significantly reduced and the energy level alignment at the SnO2 /perovskite interface becomes more matched. As a result, the champion f-PSC obtains a PCE of 21.08% and rigid PSC obtains a PCE of 21.82%, obviously surpassing the PCE of 18.82% and 19.66% of the corresponding control devices. Notably, the optimized f-PSCs exhibit outstanding mechanical durability, after 5000 cycles of bending with a 5 mm bending radius, the SnO2 -PA-based device preserves 80% of the initial PCE, while the SnO2 -based device only remains 49% of the initial value.

5.
Front Oncol ; 13: 1300535, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38074690

RESUMO

Radiotherapy and chemotherapy are effective treatments for patients with locally advanced rectal cancer (LARC) and can significantly improve the likelihood of R0 resection. Radiotherapy can be used as a local treatment to reduce the size of the tumor, improve the success rate of surgery and reduce the residual cancer cells after surgery. Early chemotherapy can also downgrade the tumor and eliminate micrometastases throughout the body, reducing the risk of recurrence and metastasis. The advent of neoadjuvant concurrent radiotherapy (nCRT) and total neoadjuvant treatment (TNT) has brought substantial clinical benefits to patients with LARC. Even so, given increasing demand for organ preservation and quality of life and the disease becoming increasingly younger in its incidence profile, there is a need to further explore new neoadjuvant treatment options to further improve tumor remission rates and provide other opportunities for patients to choose watch-and-wait (W&W) strategies that avoid surgery. Targeted drugs and immunologic agents (ICIs) have shown good efficacy in patients with advanced rectal cancer but have not been commonly used in neoadjuvant therapy for patients with LARC. In this paper, we review several aspects of neoadjuvant therapy, including radiation therapy and chemotherapy drugs, immune drugs and targeted drugs used in combination with neoadjuvant therapy, with the aim of providing direction and thoughtful perspectives for LARC clinical treatment and research trials.

6.
ACS Appl Mater Interfaces ; 15(29): 34862-34873, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37443450

RESUMO

Sn-Pb mixed perovskite solar cells (PSCs) are developing rapidly and making great progress due to their environmentally friendly advantages. High-crystalline quality perovskite films are essential for obtaining high-efficiency and -stability PSCs. Here, the DJ-phase two-dimensional (2D) perovskite (4-AMP)PbI4 (4-AMP is 4-(aminomethyl) piperidine) was used as a substrate to regulate the crystallization growth of the Sn-Pb mixed perovskite for preparing high-quality perovskite films, and the regulation mechanism was analyzed in detail. The results indicate that the suitable amount of the 2D perovskite substrate is favorable for the formation of PbI2/SnI2 films with wide intergranular gaps and vertical distribution grain boundaries. Moreover, the suitable hydrophobicity of the PbI2/SnI2 film made on the 2D perovskite substrate also provides a better template for regulating the formation and dissolution of prophase perovskite capping. In addition, the 4-AMP cations from the collapsed 2D perovskite substrate can diffuse into PbI2/SnI2 films and interact with PbI2 to form the intermediate (4-AMP)-PbI2-(4-AMP) and with SnI2 to form the 2D perovskite (4-AMP)SnI4. All of these promote the diffusion of FAI/MAI molecules and decrease the crystallization growth rate of the Sn-Pb perovskite and thus increase the conversion levels of the perovskite phase and improve the crystallization orientation and quality of the perovskite, which helps mitigate the erosion of water and oxygen. In addition, the 2D perovskite used as a substrate can passivate the buried interface defects and improve the interfacial contact. Moreover, the diffusion behavior of 4-AMP cations regulates the perovskite energy levels, which match more with those of the electron transport layer. As a result, the champion device made on the (4-AMP)PbI4 substrate acquires a power conversion efficiency (PCE) of 17.7% with an open-circuit voltage (Voc) of 0.806 V, a short-circuit current density (Jsc) of 28.97 mA cm-2, and a fill factor (FF) of 75.86%, far exceeding those of the control device. Meanwhile, the unencapsulated PSCs modified with 4-AH retain above 70% of the initial efficiency value after storage for 1200 h in N2 at room temperature and about 25% of its initial efficiency after exposure to air for nearly 300 h with RH = 30 ± 10% at room temperature, while the control device has only 30% of the initial efficiency and near-zero efficiency at the same conditions.

7.
Phys Chem Chem Phys ; 25(27): 17725-17736, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37387648

RESUMO

Due to their tunable wavelength, high color purity, bright emission and low-cost fabrication process, perovskite nanocrystals (PeNCs) have attracted broad interest and exhibited great prospects in application areas such as solar cells, light-emitting diodes, photodetectors, and lasers. Although the fabrication of PeNCs and related optoelectronic devices has witnessed rapid development over the past several years, the poor stability of PeNCs in an external environment still remains a major drawback which severely limits the further improvement and commercialization of PeNC-based devices. Therefore, various techniques and strategies have been developed to enhance the stability of PeNCs. Among them, the encapsulation strategy has been demonstrated to be an effective way to improve the stability of PeNCs. In this review, the origin of the instability of PeNCs is first analyzed to identify the importance of encapsulation, followed by a summary and discussions on recent advances in the encapsulation of PeNCs. The potential applications of encapsulated PeNCs in various optoelectronic devices are also presented to manifest the necessity of encapsulation. Finally, the further development and outlook on encapsulation of PeNCs are analyzed in order to suggest future improvements and commercialization of PeNCs and related optoelectronic devices.

8.
Sci Bull (Beijing) ; 68(9): 928-937, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37085396

RESUMO

Low-cost, solution-processed photomultiplication organic photodetectors (PM-OPDs) with external quantum efficiency (EQE) above unity have attracted enormous attention. However, their weak-light detection is unpleasant because the anode Ohmic contact causes exacerbation in dark current. Here, we introduce atomic-level chemical reaction in PM-OPDs which can simultaneously suppress dark current and increase EQE via depositing a 0.8 nm thick Al2O3 by the atomic layer deposition. Suppression in dark current mainly originates from the built-in anode Schottky junction as a result of work function decrease of hole-transporting layer of which the chemical groups can react chemically with the bottom surface of Al2O3 layer at the atomic-level. Such strategy of suppressing dark current is not adverse to charge injection under illumination; instead, responsivity enhancement is realized because charge injection can shift from cathode to anode, of which the neighborhood possesses increased photogenerated carriers. Consequently, weak-light detection limit of the forwardly-biased PM-OPD with Al2O3 treatment reaches a remarkable level of 2.5 nW cm-2, while that of the reversely-biased control is 25 times inferior. Meanwhile, the PM-OPD yields a record high EQE and responsivity of 4.31 × 108% and 1.85 × 106 A W-1, respectively, outperforming all other polymer-based PM-OPDs.

9.
Adv Mater ; 35(20): e2211591, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36918401

RESUMO

Reducing the excitation threshold to minimize the Joule heating is critical for the realization of perovskite laser diodes. Although bound excitons are promising for low threshold laser, how to generate them at room temperature for laser applications is still unclear in quasi-2D perovskite-based devices. In this work, via engineering quasi-2D perovskite PEA2 (CH3 NH3 )n -1 Pbn Br3 n +1 microscopic grains by the anti-solvent method, room-temperature multiexciton radiative recombination is successfully demonstrated at a remarkably low pump density of 0.97 µJ cm-2 , which is only one-fourth of that required in 2D CdSe nanosheets. In addition, the well-defined translational momentum in quasi-2D perovskite grains can restrict the Auger recombination which is detrimental to radiative emission. Furthermore, the quasi-2D perovskite grains are favorable for increasing binding energies of excitons and biexcitons and so as the related radiative recombination. Consequently, the prepared phase quasi-2D perovskite film renders a threshold of room-temperature stimulated emission as low as 13.7 µJ cm-2 , reduced by 58.6% relative to the amorphous counterpart with larger grains. The findings in this work are expected to facilitate the development of solution-processable perovskite multiexcitonic laser diodes.

10.
Radiat Oncol ; 18(1): 50, 2023 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-36906568

RESUMO

BACKGROUND: During the last decades, radiotherapy (RT) for non-small cell lung cancer (NSCLC) with brain metastases (BM) has been developed. However, the lack of predictive biomarkers for therapeutic responses has limited the precision treatment in NSCLC-BM. PATIENTS AND METHODS: In order to find the predictive biomarkers for RT, we investigated the influence of RT on the cell-free DNA (cfDNA) from cerebrospinal fluid (CSF) and the frequency of T cell subsets of NSCLC patients with BM. A total of 19 patients diagnosed as NSCLC with BM were enrolled. The CSF from 19 patients and matched plasma samples from 11 patients were collected before RT, during RT, and after RT. The cfDNA from CSF and plasma were extracted, and the cerebrospinal fluid tumor mutation burden (cTMB) was calculated after through next-generation sequencing. The frequency of T cell subsets in peripheral blood was using flow cytometry. RESULTS: The detection rate of cfDNA was higher in CSF compared to plasma in the matched samples. The mutation abundance of cfDNA in CSF was decreased after RT. However, no significant difference was observed in cTMB before and after RT. Although the median intracranial progression-free survival (iPFS) has not yet been reached in patients with decreased or undetectable cTMB, there was a trend that these patients possessed longer iPFS compared to those with stable or increased cTMB (HR 0.28, 95% CI 0.07-1.18, P = 0.067). The proportion of CD4+T cells in peripheral blood was decreased after RT. CONCLUSION: Our study indicates that cTMB can serve as a prognostic biomarker in NSCLC patients with BMs.


Assuntos
Neoplasias Encefálicas , Carcinoma Pulmonar de Células não Pequenas , Ácidos Nucleicos Livres , Neoplasias Pulmonares , Humanos , Biomarcadores Tumorais/líquido cefalorraquidiano , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/secundário , Carcinoma Pulmonar de Células não Pequenas/patologia , Ácidos Nucleicos Livres/líquido cefalorraquidiano , Neoplasias Pulmonares/patologia , Mutação , Prognóstico
11.
Environ Sci Pollut Res Int ; 30(12): 35223-35237, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36527562

RESUMO

Deep geological disposal of high-level radioactive waste is a feasible method for solving the problem of spent fuel storage in China. High-level radioactive waste releases heat during the decay process, which increases the temperature of the surrounding rock in the repository, resulting in a significant increase in radon concentration. In this study, the surrounding rock (granite) of a high-level radioactive waste repository was taken as the research object and, based on the similarity principle, an orthogonal test designed. Similar materials of uranium-containing granite were prepared in the laboratory and the physical and mechanical properties and cumulative radon concentration of granite samples assessed under different temperatures (25, 50, 100, 150, and 200 °C). The results showed that, with increased temperature, the compressive and tensile strengths of samples gradually increased and their pore volume gradually decreased. After heat treatment, the longitudinal wave velocity and thermal conductivity of samples decreased linearly with increased temperature. The radon exhalation rate first increased and then decreased, with the rate reaching a maximum at 100 °C. The radon exhalation rate of single-sided and double-sided samples was 0.00914 and 0.00460 Bq·m-2·s-1, respectively. When the temperature was 25-100 °C, the dominant stage was pore water. The radon exhalation rates of samples were positively correlated with compressive and tensile strengths and negatively correlated with pore volume, longitudinal wave velocity, and thermal conductivity. The temperature of 100-200 °C was range of the dominant stage of pore structure. The conclusions obtained in this study can provide theoretical support for radon reduction and radon control of granite in high temperature environments.


Assuntos
Monitoramento de Radiação , Resíduos Radioativos , Radônio , Urânio , Radônio/análise , Temperatura , Urânio/análise , Temperatura Alta , Expiração , Monitoramento de Radiação/métodos
12.
J Biochem Mol Toxicol ; : e23003, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36468373

RESUMO

The above article, published online on 5 December 2022, on Wiley Online Library (https://doi.org/10.1002/jbt.23003), has been withdrawn by agreement between the journal Editor in Chief, Hari Bhat, and Wiley Periodicals, LLC. The withdrawal has been agreed due to a technical error at the publisher that caused the article to be mistakenly published online although publication had been canceled because the authors did not approve their proof.

13.
Nanomaterials (Basel) ; 12(17)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36080121

RESUMO

Organic photodetectors (OPDs) have aroused intensive attention for signal detection in industrial and scientific applications due to their advantages including low cost, mechanical flexibility, and large-area fabrication. As one of the most common organic light-emitting materials, 8-hydroxyquinolinato aluminum (Alq3) has an absorption wavelength edge of 460 nm. Here, through the introduction of Ag nanoparticles (Ag NPs), the spectral response range of the Alq3-based OPD was successfully extended to the near-infrared range. It was found that introducing Ag NPs can induce rich plasmonic resonances, generating plenty of hot electrons, which could be injected into Alq3 and then be collected. Moreover, as a by-product of introducing Ag NPs, the dark current was suppressed by around two orders of magnitude by forming a Schottky junction on the cathode side. These two effects in combination produced photoelectric signals with significant contrasts at wavelengths beyond the Alq3 absorption band. It was found that the OPD with Ag NPs can stably generate electric signals under illumination by pulsed 850 nm LED, while the output of the reference device included no signal. Our work contributes to the development of low-cost, broadband OPDs for applications in flexible electronics, bio-imaging sensors, etc.

14.
ACS Nano ; 16(8): 12767-12776, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35916454

RESUMO

Wavelength-tunable semiconductor nanolasers have attracted tremendous attention for their tunable emissions and robust stability, bringing possibilities for various applications, including nanophotonic circuits, solid-state white-light sources, wavelength-converted devices, and on-chip optical communications. Here, we report on the demonstration of broadband-tunable, single-mode nanolasers based on high-quality alloyed single crystalline CdS1-xSex (x = 0-1) nanotripods with well-formed facets fabricated using a conventional CVD approach. Microstructural characterization and optical investigations reveal that these structures are crystalline with composition-tunable CdS1-xSex alloys. Microphotoluminescence spectra and mapping of these nanotripods exhibit emissions with continuous wavelengths from 509 to 712 nm, further demonstrating that the CdS1-xSex alloys have tunable bandgaps due to the composition gradient. Additionally, under a pulse laser illumination, room-temperature single-mode lasing is clearly observed from these nanotripods cavities, which shows almost identical emission lines with a high-quality factor of ∼1231. More importantly, wavelength continuously tunable nanolasers from 520 to 738 nm are successfully constructed using these bandgap gradient nanotripods. The capability to fabricate high-quality tunable nanolasers represents a significant step toward high-integration optical circuits and photonics communications.

15.
Materials (Basel) ; 15(8)2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35454430

RESUMO

Hot-electron photodetectors (HEPDs) are triggering a strong surge of interest in applications of image sensors and optics communication, since they can realize photoelectric responses when the incident photon energy is lower than the bandwidth of the semiconductor. In traditional HEPD systems, the metal layers are dressed with regular gratings, which can only excite plasmonic resonance over a narrow bandwidth, limiting the hot-electron photoelectric effect. To break this limitation, hybrid plasmonic nanostructures should be applied in HEPDs. Here, we propose a TiO2 based HEPD device incorporated with a hybrid plasmonic nanostructure, which consists of Au nanoparticles (Au NPs) and a conformal transparent Au film. With the assistance of the plasmonic resonances excited in this hybrid nanostructure, the spectrum of the photocurrent response is significantly broadened from the UV band to the visible and near-infrared (NIR) ranges. It is demonstrated that at the wavelengths of 660 nm and 850 nm, the photocurrent in the hybrid HEPD device is enhanced by 610% and 960%, respectively, compared with the counterparts without the addition of Au NPs. This work promotes the development of high performances HEPDs, offering an alternative strategy for realizing photodetection and image sensing in the NIR range.

16.
Nanotechnology ; 33(26)2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35316799

RESUMO

Twisted graphene, including magic angle graphene, has attracted extensive attentions for its novel properties recently. However, twisted graphene is intrinsically unstable and this will obstruct their application in practice, especially for twisted nano graphene. The twist angles between adjacent layers will change spontaneously. This relaxation process will be accelerated under heat and strain. To solve this problem, we propose a strategy of pillaring twisted graphene by organic linkers in theory. The necessity and feasibility of this strategy is proved by numerical calculation.

17.
Phys Chem Chem Phys ; 24(12): 7451-7457, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35274655

RESUMO

Perovskite quantum dots (PQDs) are promising interface modification materials for perovskite solar cells (PSCs). However, due to the limitation of the preparation method, it is hard to use PQDs as substrates for the growth of perovskite films by the common solution process. In this work, by introducing the rare earth element Ce into PQDs with the vacuum freezing and drying technology, we have successfully improved the solvent stability of PQDs. Moreover, we propose a technology, PQD dynamically mediated growth of perovskite film (PDMG), to prepare high-quality perovskite films, which can avoid the formation of PQD charge-blocking layers. Thanks to the improvement of perovskite crystallinity and the charge transport ability, the PCE is improved from 10.44% to 12.14% for CsPbI2Br PSCs and from 14.43% to 16.38% for CsPbI3 PSCs. Our work opens an avenue for using PQDs as substrates in the fabrication of highly efficient PSCs.

18.
ACS Appl Mater Interfaces ; 14(5): 7417-7427, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35077148

RESUMO

High-quality perovskite films are beneficial for fabricating perovskite solar cells (PSCs) with excellent photoelectric performance. The substrate on which the perovskite film grows plays a profound role in improving the crystallization quality of the perovskite film. Here, we proposed a novel method for optimizing CsPbI3 perovskite films, that is, two-dimensional (2D) perovskite substrate-assisted growth (2D-PSAG) method. The prepared PEA2PbI4 2D perovskite with proper wettability and roughness is used as a substrate to fabricate the high-quality CsPbI3 film. Moreover, it is found that PEA cations show a vertical gradient distribution within the whole CsPbI3 film because of their bottom-up self-diffusion. Also, PEA cations induce the moderate distortion of [PbI6]4- octahedron and slight lattice contraction of CsPbI3 by chemically bonding between Pb and N atoms. Surprisingly, the trace amounts of PEA cations lead to a bottom-up gradient phase transition from γ-CsPbI3 to ß-CsPbI3. Therefore, the energy-level alignment becomes more matched at the interface of the perovskite layer/hole transport layer (poly3-hexylthiophene, P3HT), which denotes a large improvement of hole transport and extraction in PSCs made with the 2D-PSAG method. As a result, the CsPbI3-based PSCs with P3HT as a hole transport layer exhibit a champion efficiency of 17.13%, while the control device exhibits a PCE of only 14.16%. The PSCs made by the 2D-PSAG method retain above 70% of the initial PCE value after storage of 9 days in air (RH 10-20%), while the control device decomposes completely after 9 days. The improved stability could originate from the steric effects of PEA cations and the high crystallization quality of the mixed-phase CsPbI3 film. Therefore, 2D-PSAG is a novel and promising strategy to develop all-inorganic PSCs with high performance and stability.

19.
Nanoscale Res Lett ; 17(1): 8, 2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-34989892

RESUMO

The outstanding optoelectrical properties and high-quality factor of whispering gallery mode perovskite nanocavities make it attractive for applications in small lasers. However, efforts to make lasers with better performance have been hampered by the lack of efficient methods for the synthesis and transfer of perovskite nanocavities on desired substrate at quality required for applications. Here, we report transfer printing of perovskite nanocavities grown by chemical vapor deposition from mica substrate onto SiO2 substrate. Transferred perovskite nanocavity has an RMS roughness of ~ 1.2 nm and no thermal degradation in thermal release process. We further use femtosecond laser to excite a transferred perovskite nanocavity and measures its quality factor as high as 2580 and a lasing threshold of 27.89 µJ/cm2 which is almost unchanged as compared with pristine perovskite nanocavities. This method represents a significant step toward the realization of perovskite nanolasers with smaller sizes and better heat management as well as application in optoelectronic devices.

20.
Environ Sci Pollut Res Int ; 29(14): 20603-20616, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34741268

RESUMO

Uranium tailing ponds are a potential major source of radioactive pollution. Solidification treatment can control the diffusion and migration of radioactive elements in uranium tailings to safeguard the surrounding ecological environment. A literature review and field investigation were conducted in this study prior to fabricating 11 solidified uranium tailing samples with different proportions of PVA fiber, basalt fiber, metakaolin, and fly ash, and the weight percentage of uranium tailings in the solidified body is 61.11%. The pore structure, volume resistivity, compressive strength, radon exhalation rate variations, and U(VI) leaching performance of the samples were analyzed. The pore size of the solidified samples is mainly between 1 and 50 nm, the pore volume is between 2.461 and 5.852 × 10-2 cm3/g, the volume resistivity is between 1020.00 and 1937.33 Ω·m, and the compressive strength is between 20.61 and 36.91 MPa. The radon exhalation rate is between 0.0397 and 0.0853 Bq·m-2·s-1. The cumulative leaching fraction of U(VI) is between 2.095 and 2.869 × 10-2 cm, and the uranium immobilization rate is between 83.46 and 85.97%. Based on a comprehensive analysis of the physical and mechanical properties, radon exhalation rates, and U(VI) leaching performance of the solidified samples, the basalt fiber is found to outperform PVA fiber overall. The solidification effect is optimal when 0.6% basalt fiber is added.


Assuntos
Indústrias Extrativas e de Processamento , Resíduos Radioativos , Poluentes Radioativos do Solo , Urânio , Gerenciamento de Resíduos , Cinza de Carvão/análise , Difusão , Locais de Resíduos Perigosos , Proteção Radiológica/métodos , Resíduos Radioativos/análise , Radônio/análise , Silicatos/análise , Poluentes Radioativos do Solo/análise , Poluentes Radioativos do Solo/química , Urânio/análise , Gerenciamento de Resíduos/métodos
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