Enhanced UV Stability of Perovskite Solar Modules via Downshifting Luminescent Organic-Inorganic Copper Halide Film with Near-Unity Efficiency.

Obtaining efficient perovskite solar modules (PSMs) with enhanced UV stability is essential for their practical applications, yet remains a significant challenge. In this work, a highly efficient organic-inorganic copper halide downshifting film that significantly enhances the UV stability of PSMs is demonstrated by converting high-energy harmful UV photons into beneficial visible light photons that contribute to photovoltaic performance. The tetrapropylammonium (TPA) cation is selected as the main framework to synthesize a series of organic-inorganic copper halides, denoted as BrI.

Metal chalcogenide electron extraction layers for nip-type tin-based perovskite solar cells.

Tin-based perovskite solar cells have garnered attention for their biocompatibility, narrow bandgap, and long thermal carrier lifetime. However, nip-type tin-based perovskite solar cells have underperformed largely due to the indiscriminate use of metal oxide electron transport layers originally designed for nip-type lead-based perovskite solar cells. Here, we reveal that this underperformance is caused by oxygen vacancies and deeper energy levels in metal oxide.

Room Temperature Crystallized Phase-Pure α-FAPbI Perovskite with In-Situ Grain-Boundary Passivation.

Energy loss in perovskite grain boundaries (GBs) is a primary limitation toward high-efficiency perovskite solar cells (PSCs). Two critical strategies to address this issue are high-quality crystallization and passivation of GBs. However, the established methods are generally carried out discretely due to the complicated mechanisms of grain growth and defect formation.

Investigation of the Role of KSO Electrolyte in Hole Transport Layer for Efficient Quasi-2D Perovskite Light-Emitting Diodes.

Quasi-two-dimensional (2D) perovskite light-emitting diodes are promising light sources for color display and lighting. However, poor carrier injection and transport between the bottom hole transport layer (HTL) and perovskite limit the device performance. Here we demonstrate a simple and effective way to modify the HTL for enhancing the performance of perovskite light-emitting diodes (PeLEDs).

Optoelectronic synapses based on a triple cation perovskite and Al/MoO interface for neuromorphic information processing.

Optoelectronic synaptic transistors are attractive for applications in next-generation brain-like computation systems, especially for their visible-light operation and in-sensor computing capabilities. However, from a material perspective, it is difficult to build a device that meets expectations in terms of both its functions and power consumption, prompting the call for greater innovation in materials and device construction. In this study, we innovatively combined a novel perovskite carrier supply layer with an Al/MoO interface carrier regulatory layer to fabricate optoelectronic synaptic devices, namely Al/MoO/CsFAMA/ITO transistors.

Intermediate Phase Free α-FAPbI Perovskite via Green Solvent Assisted Perovskite Single Crystal Redissolution Strategy.

Perovskite single-crystal redissolution (PSCR) strategy is highly desired for efficient formamidinium lead triiodide (FAPbI ) perovskite photovoltaics with enhanced phase purity, improved film quality, low trap-state density, and good stability. However, the phase transition and crystallization dynamics of FAPbI remain unclear in the PSCR process compared to the conventional fabrication from the mixing of precursor materials. In this work, a green-solvent-assisted (GSA) method is employed to synthesize centimeter-sized α-FAPbI single crystals, which serve as the high-purity precursor to fabricate perovskite films.

Green Solvent Polishing Enables Highly Efficient Quasi-2D Perovskite Solar Cells.

Preferred crystalline orientation at the surface of quasi-2D organic-inorganic halide perovskites is crucial to promote vertical carrier transport and interface carrier extraction, which further contribute to device efficiency and stability in photovoltaic applications. However, loose unoriented and defective surfaces are inevitably formed in the crystallization process, especially with the introduction of bulky organic cations into the quasi-2D perovskites. Here, a facile and effective surface polishing method using a natural-friendly green solvent, 2,2,2-trifluoroethanol, is proposed to reconstruct the surface.

Highly Efficient and Stable Self-Powered Mixed Tin-Lead Perovskite Photodetector Used in Remote Wearable Health Monitoring Technology.

Realization of remote wearable health monitoring (RWHM) technology for the flexible photodiodes is highly desirable in remote-sensing healthcare systems used in space stations, oceans, and forecasting warning, which demands high external quantum efficiency (EQE) and detectivity in NIR region. Traditional inorganic photodetectors (PDs) are mechanically rigid and expensive while the widely reported solution-processed mixed tin-lead (MSP) perovskite photodetectors (PPDs) exhibit a trade-off between EQE and detectivity in the NIR region. Herein, a novel functional passivating antioxidant (FPA) strategy has been introduced for the first time to simultaneously improve crystallization, restrain Sn oxidization, and reduce defects in MSP perovskite films by multiple interactions between thiophene-2-carbohydrazide (TAH) molecules and cations/anions in MSP perovskite.

Strain Release and Defect Passivation in Formamidinium-Dominated Perovskite via a Novel in-Plane Thermal Gradient Assisted Crystallization Strategy.

It is essential to release annealing induced strain during the crystallization process to realize efficient and stable perovskite solar cells (PSCs), which does not seem achievable using the conventional annealing process. Here we report a novel and facile thermal gradient assisted crystallization strategy by simply introducing a slant angle between the preheated hot plate and the substrate. A distinct crystallization sequence resulted along the in-plane direction pointing from the hot side to the cool side, which effectively reduced the crystallization rate, controlled the perovskite grain growth, and released the in-plane tensile strain.

Improved highly efficient Dion-Jacobson type perovskite light-emitting diodes by effective surface polarization architecture.

Quasi-two-dimensional (quasi-2D) perovskites are emerging as promising materials for highly stable light-emitting diodes (LEDs). However, their lower charge transport mobilities and higher defect densities may constrain their light-emitting efficiency. Here, we combine an excessive-salt-assisted (ESA) process with antisolvent treatments to inhibit the defects in Dion-Jacobson-type perovskite LEDs.

Utilization of Calcium Carbide Residue as Solid Alkali for Preparing Fly Ash-Based Geopolymers: Dependence of Compressive Strength and Microstructure on Calcium Carbide Residue, Water Content and Curing Temperature.

Calcium carbide residue (CCR) is a solid waste resulting from acetylene gas production. In this study, CCR was used as an alkali activator to prepare fly ash (FA)-based geopolymers without any alkali supplementation. We studied the factors (FA/CCR ratio, curing temperature, and water/binder ratio) influencing the mechanical property of FA/CCR-based geopolymers.

Phase Modulation by Vacuum Poling toward Enhanced Performance of Quasi-Two-Dimensional Bromide Perovskite-Based Light-Emitting Diodes.

As a new kind of highly efficient luminescent materials, quasi-two-dimensional (quasi-2D) perovskites show great potential in industrial display applications. In this work, the poling methods are used in modulating the phase arrangement in quasi-2D perovskite light-emitting diodes (PeLEDs). We find the effective modulation of different phase components in uniform arrangement can enhance both brightness and current efficiency to 30 810 cd/m and 8.

Surface Modification of SnO via MAPbI Nanowires for a Highly Efficient Non-Fullerene Acceptor-Based Organic Solar Cell.

These days, organic-inorganic hybrid perovskites (OIHP) and non-fullerene acceptor (NFA) molecules are all at the frontiers of research and development in the domain of photovoltaics. A careful design and use of inorganic transparent metal oxides with wide band gaps as electron and hole transport layers are critically important for highly efficient and stable solar cells. As one of the most favorable electron transport materials, tin oxide (SnO), which has been frequently utilized in highly efficient OIHP solar cells, is rarely seen in the application of NFA organic bulk heterojunction (BHJ) solar cells.

Lake sedimentary biogenic silica from diatoms constitutes a significant global sink for aluminium.

Diatoms play an important role in marine biogeochemical cycle of aluminum (Al), as dissolved Al is taken up by diatoms to build their siliceous frustules and is involved in the sedimentation of diatomaceous biogenic silica (BSi). The Al incorporation in BSi facilitates decreasing the dissolution of marine BSi and thus substantially influences the biochemical processes driven by diatoms, such as CO sequestration. However, the role of lake BSi in the terrestrial biochemical Al cycle has not been explored, though lakes represent the second-largest sink for BSi.

Effect of surface recombination in high performance white-light CHNHPbI single crystal photodetectors.

Methylammonium lead iodide (CHNHPbI), with the organic-inorganic hybrid perovskite (OIHP) structure, has gained tremendous research interest due to its excellent photo-electron conversion ability in the application of photovoltaics. Despite its solution processed polycrystalline thin film form in solar cells, the single crystalline counterpart may offer some incredibly novel optoelectronic functionalities. In this work, a sizable (>5 mm) and high quality CHNHPbI single crystal has been synthesized by the inverse temperature crystallization method, and a white-light photodetector of the structure glass/ITO/Ga/ CHNHPbI/Au was fabricated.

Causes of Visual Impairment and Blindness in the 2006 and 2014 Nine-Province Surveys in Rural China.

Purpose: To investigate the primary causes of visual impairment and blindness in rural China.

Design: Population-based, cross-sectional study.

Methods: Geographic cluster sampling was used in randomly selecting residents from a rural county/district within 9 provinces in the East Coast, Inland Middle, and West regions of mainland China.

Evaluation of Maltose-Based Cationic Liposomes with Different Hydrophobic Tails for Plasmid DNA Delivery.

In this paper, three cationic glycolipids with different hydrophobic chains Malt-DiC12MA (), Malt-DiC14MA () and Malt-DiC16MA () were constructed by using maltose as starting material via peracetylation, selective 1--deacetylation, trichloroacetimidation, glycosylation, azidation, deacetylation, Staudinger reaction, tertiary amination and quaternization. Target compounds and some intermediates were characterized by ¹H-NMR, C-NMR, ¹H-¹H COSY and ¹H-C HSQC. The results of gel electrophoresis assay, atomic force microscopy images (AFM) and dynamic light scattering (DLS) demonstrate that all the liposomes could efficiently bind and compact DNA (N/P ratio less than 2) into nanoparticles with proper size (88 nm-146 nm, PDI < 0.

In situ hydrothermal synthesis of a novel hierarchically porous TS-1/modified-diatomite composite for methylene blue (MB) removal by the synergistic effect of adsorption and photocatalysis.

Hierarchically porous TS-1/modified-diatomite composites with high removal efficiency for methylene blue (MB) were prepared via a facile in situ hydrothermal route. The surface charge state of the diatomite was modified to enhance the electrostatic interactions, followed by in situ hydrothermal coating with TS-1 nanoparticles. The zeolite loading amount in the composites could be adjusted by changing the hydrothermal time.

Possible mechanism of structural incorporation of Al into diatomite during the deposition process I. Via a condensation reaction of hydroxyl groups.

The structural incorporation of aluminium (Al) into diatomite is investigated by preparing several Al-diatomite composites by loading an Al precursor, hydroxyl aluminum polymer (Al13), onto the surface of diatomite and heating at various temperatures. The results indicate that Al was incorporated and implanted into the structure of diatomite by the condensation reaction of the hydroxyl groups of Al13 and diatomite, and the Si-O-Al(OH) groups were formed during the condensation reaction. Al incorporation by the condensation reaction of hydroxyl groups of Al13 with single silanols of diatomite occurred more readily than that with geminal silanols.

Surface silylation of natural mesoporous/macroporous diatomite for adsorption of benzene.

Naturally occurring porous diatomite (Dt) was functionalized with phenyltriethoxysilane (PTES), and the PTES-modified diatomite (PTES-Dt) was characterized using diffuse reflectance Fourier transform infrared spectroscopy, nitrogen adsorption, nuclear magnetic resonance spectroscopy, X-ray photoelectron spectroscopy, and thermogravimetric analysis. After silylation, a functional group (-C6H5, phenyl) was successfully introduced onto the surface of Dt. PTES-Dt exhibited hydrophobic properties with a water contact angle (WCA) as high as 120°±1°, whereas Dt was superhydrophilic with a WCA of 0°.

Facile preparation of hierarchically porous diatomite/MFI-type zeolite composites and their performance of benzene adsorption: the effects of NaOH etching pretreatment.

Hierarchically porous diatomite/MFI-type zeolite (Dt/Z) composites with excellent benzene adsorption performance were prepared. The hierarchical porosity was generated from the microporous zeolite coated at the surface of diatom frustules and from the macroporous diatomite support. A facile NaOH etching method was employed for the first time to treat the frustule support, followed by hydrothermal growth of MFI-type zeolite at the surface of frustules previously seeded with nanocrystalline silicalite-1 (Sil-1).

Preparation of porous diatomite-templated carbons with large adsorption capacity and mesoporous zeolite K-H as a byproduct.

In this study, KOH activation was performed to enhance the porosity of the diatomite-templated carbon and to increase its adsorption capacity of methylene blue (MB). In addition to serving as the activation agent, KOH was also used as the etchant to remove the diatomite templates. Zeolite K-H was synthesized as a byproduct via utilization of the resultant silicon- and potassium-containing solutions created from the KOH etching of the diatomite templates.