Sub-Second Long Lifetime Triplet Exciton Reservoir for Highly Efficient and Stable Organic Light-Emitting Diode.

In organic light-emitting diode (OLED), achieving high efficiency requires effective triplet exciton confinement by carrier-transporting materials, which typically have higher triplet energy (ET ) than the emitter, leading to poor stability. Here, an electron-transporting material (ETM), whose ET is 0.32 eV lower than that of the emitter is reported. In devices, it surprisingly exhibits strong confinement effect and generates excellent efficiency. Additionally, the device operational lifetime is 4.9 times longer than the device with a standard ETM, 1,3,5-tri(1-phenyl-1H-benzo[d]imidazol-2-yl) phenyl (whose ET 0.36 eV is higher than the emitter). This anomalous finding is ascribed to the exceptionally long triplet state lifetime (≈0.2 s) of the ETM. It is named as long-lifetime triplet exciton reservoir effect. The systematic analysis reveals that the long triplet lifetime of ETM can compensate the requirement for high ET with the help of endothermic energy transfer. Such combination of low ET and long lifetime provides equivalent exciton confinement effect and high molecular stability simultaneously. It offers a novel molecular design paradigm for breaking the dilemma between high efficiency and prolonged operational lifetime in OLEDs.

Buried-Interface Engineering Enables Efficient and 1960-Hour ISOS-L-2I Stable Inverted Perovskite Solar Cells.

High-performance perovskite solar cells (PSCs) typically require interfacial passivation, yet this is challenging for the buried interface, owing to the dissolution of passivation agents during the deposition of perovskites. Here, this limitation is overcome with in situ buried-interface passivation-achieved via directly adding a cyanoacrylic-acid-based molecular additive, namely BT-T, into the perovskite precursor solution. Classical and ab initio molecular dynamics simulations reveal that BT-T spontaneously may self-assemble at the buried interface during the formation of the perovskite layer on a nickel oxide hole-transporting layer. The preferential buried-interface passivation results in facilitated hole transfer and suppressed charge recombination. In addition, residual BT-T molecules in the perovskite layer enhance its stability and homogeneity. A power-conversion efficiency (PCE) of 23.48% for 1.0 cm2 inverted-structure PSCs is reported. The encapsulated PSC retains 95.4% of its initial PCE following 1960 h maximum-power-point tracking under continuous light illumination at 65 °C (i.e., ISOS-L-2I protocol). The demonstration of operating-stable PSCs under accelerated ageing conditions represents a step closer to the commercialization of this emerging technology.

PANoptosis in vascular smooth muscle cells regulated by TNF-α/IL-1ß can be a new target for alleviating the progression of abdominal aortic aneurysm.

PANoptosis is an inflammatory programmed cell death (PCD) regulated by multifaceted PANoptosome complexes with major features of pyroptosis, apoptosis, and/or necroptosis that cannot be accounted for by any of these PCD pathways alone. The aim of this study was to investigate the role of PANoptosis on the occurrence and development of abdominal aortic aneurysm (AAA). Clinical samples of patients with AAA, angiotensin II (ANG II)-induced AAA mouse model, and ANG II-induced vascular smooth muscle cells (VSMCs) in vitro model were used for investigation on PANoptosis features. The expressions of ZBP1, AIM2, and other markers related to pyroptosis, apoptosis, and necroptosis elevated obviously in aortic wall tissues of patients with AAA, mice with AAA, and ANG II-treated VSMCs. ANG II treatment increased inflammatory cytokines levels in VSMCs. The stimulation of tumor necrosis factor-α (TNF-α) or interleukin-1ß (IL-1ß) alone promoted VSMCs death, and the effect of TNF-α combined with IL-1ß is more obvious. The expressions of ZBP1, AIM2, and related markers of pyroptosis, apoptosis, and necroptosis were increased by TNF-α and IL-1ß combined treatment. Inhibition of TNF-α and/or IL-1ß in mice with AAA improved the AAA pathology, reduced the loss of VSMCs, decreased the expression of ZBP1 and AIM2, and markers associated with pyroptosis, apoptosis, and necroptosis. PANoptosis features were observed in aortic wall tissues of patients with AAA, mice with AAA, and ANG II-treated VSMCs. The inhibition of TNF-α and IL-1ß can alleviate PANoptosis in mice with AAA, which provides a new strategy for the prevention and treatment of AAA.NEW & NOTEWORTHY Early detection, diagnosis, and treatment are very important to improve the quality of life and prognosis of patients with abdominal aortic aneurysm (AAA). Based on the findings of apoptosis, necroptosis, and pyroptosis (PANoptosis) in AAA clinical samples, this study further explored the molecular mechanism in vivo and in vitro. Specifically, inhibition of tumor necrosis factor-α and interleukin-1ß can reduce PANoptosis in vascular smooth muscle cell and thus alleviate the process of AAA.

Low-loss contacts on textured substrates for inverted perovskite solar cells.

Inverted perovskite solar cells (PSCs) promise enhanced operating stability compared to their normal-structure counterparts1-3. To improve efficiency further, it is crucial to combine effective light management with low interfacial losses4,5. Here we develop a conformal self-assembled monolayer (SAM) as the hole-selective contact on light-managing textured substrates. Molecular dynamics simulations indicate that cluster formation during phosphonic acid adsorption leads to incomplete SAM coverage. We devise a co-adsorbent strategy that disassembles high-order clusters, thus homogenizing the distribution of phosphonic acid molecules, and thereby minimizing interfacial recombination and improving electronic structures. We report a laboratory-measured power conversion efficiency (PCE) of 25.3% and a certified quasi-steady-state PCE of 24.8% for inverted PSCs, with a photocurrent approaching 95% of the Shockley-Queisser maximum. An encapsulated device having a PCE of 24.6% at room temperature retains 95% of its peak performance when stressed at 65 °C and 50% relative humidity following more than 1,000 h of maximum power point tracking under 1 sun illumination. This represents one of the most stable PSCs subjected to accelerated ageing: achieved with a PCE surpassing 24%. The engineering of phosphonic acid adsorption on textured substrates offers a promising avenue for efficient and stable PSCs. It is also anticipated to benefit other optoelectronic devices that require light management.

Engineering ligand reactivity enables high-temperature operation of stable perovskite solar cells.

Perovskite solar cells (PSCs) consisting of interfacial two- and three-dimensional heterostructures that incorporate ammonium ligand intercalation have enabled rapid progress toward the goal of uniting performance with stability. However, as the field continues to seek ever-higher durability, additional tools that avoid progressive ligand intercalation are needed to minimize degradation at high temperatures. We used ammonium ligands that are nonreactive with the bulk of perovskites and investigated a library that varies ligand molecular structure systematically. We found that fluorinated aniliniums offer interfacial passivation and simultaneously minimize reactivity with perovskites. Using this approach, we report a certified quasi-steady-state power-conversion efficiency of 24.09% for inverted-structure PSCs. In an encapsulated device operating at 85°C and 50% relative humidity, we document a 1560-hour T85 at maximum power point under 1-sun illumination.

Separating Crystal Growth from Nucleation Enables the In Situ Controllable Synthesis of Nanocrystals for Efficient Perovskite Light-Emitting Diodes.

Colloidal perovskite nanocrystals (PNCs) display bright luminescence for light-emitting diode (LED) applications; however, they require post-synthesis ligand exchange that may cause surface degradation and defect formation. In situ-formed PNCs achieve improved surface passivation using a straightforward synthetic approach, but their LED performance at the green wavelength is not yet comparable with that of colloidal PNC devices. Here, it is found that the limitations of in situ-formed PNCs stem from uncontrolled formation kinetics: conventional surface ligands confine perovskite nuclei but fail to delay crystal growth. A bifunctional carboxylic-acid-containing ammonium hydrobromide ligand that separates crystal growth from nucleation is introduced, leading to the formation of quantum-confined PNC solids exhibiting a narrow size distribution. Controlled crystallization is further coupled with defect passivation using deprotonated phosphinates, enabling improvements in photoluminescence quantum yield to near unity. Green LEDs are fabricated with a maximum current efficiency of 109 cd A-1 and an average external quantum efficiency of 22.5% across 25 devices, exceeding the performance of their colloidal PNC-based counterparts. A 45.6 h operating half-time is further documented for an unencapsulated device in N2 with an initial brightness of 100 cd m-2 .

Study on the effect of enzymatic treatment of tobacco on HnB cigarettes and microbial succession during fermentation.

Starch and cellulose are the fundamental components of tobacco, while their excessive content will affect the quality of tobacco. Enzymatic treatment with different enzymes is a promising method to modulate the chemical composition and improve the sensory quality of tobacco leaves. In this study, enzymatic treatments, such as amylase, cellulase, and their mixed enzymes, were used to improve tobacco quality, which could alter the content of total sugar, reducing sugar, starch, and cellulose in tobacco leaves. The amylase treatment changed surface structure of tobacco leaves, increased the content of neophytadiene in tobacco by 16.48%, and improved the total smoking score of heat-not-burn (HnB) cigarette products by 5.0 points compared with the control. The Bacillus, Rubrobacter, Brevundimonas, Methylobacterium, Stenotrophomonas, Acinetobacter, Pseudosagedia-chlorotica, and Sclerophora-peronella were found to be significant biomarkers in the fermentation process by LEfSe analysis. The Basidiomycota and Agaricomycetes were significantly correlated with aroma and flavor, taste, and total score of HnB. The results showed that microbial community succession occurred due to amylase treatment, which promoted the formation of aroma compounds, and regulated the chemical composition of tobacco, and improved tobacco quality during tobacco fermentation. This study provides a method for enzymatic treatment to upgrade the quality of tobacco raw materials, thereby improving the quality of HnB cigarettes, and the potential mechanism is also revealed by chemical composition and microbial community analysis. KEY POINTS: Enzymatic treatment can change the chemical composition of tobacco leaves. The microbial community was significantly affected by enzymatic treatment. The quality of HnB cigarettes was significantly improved by amylase treatment.

Suppressed phase segregation for triple-junction perovskite solar cells.

The tunable bandgaps and facile fabrication of perovskites make them attractive for multi-junction photovoltaics1,2. However, light-induced phase segregation limits their efficiency and stability3-5: this occurs in wide-bandgap (>1.65 electron volts) iodide/bromide mixed perovskite absorbers, and becomes even more acute in the top cells of triple-junction solar photovoltaics that require a fully 2.0-electron-volt bandgap absorber2,6. Here we report that lattice distortion in iodide/bromide mixed perovskites is correlated with the suppression of phase segregation, generating an increased ion-migration energy barrier arising from the decreased average interatomic distance between the A-site cation and iodide. Using an approximately 2.0-electron-volt rubidium/caesium mixed-cation inorganic perovskite with large lattice distortion in the top subcell, we fabricated all-perovskite triple-junction solar cells and achieved an efficiency of 24.3 per cent (23.3 per cent certified quasi-steady-state efficiency) with an open-circuit voltage of 3.21 volts. This is, to our knowledge, the first reported certified efficiency for perovskite-based triple-junction solar cells. The triple-junction devices retain 80 per cent of their initial efficiency following 420 hours of operation at the maximum power point.

CsAGP: Detecting Alzheimer's disease from multimodal images via dual-transformer with cross-attention and graph pooling.

Alzheimer's disease (AD) is a terrible and degenerative disease commonly occurring in the elderly. Early detection can prevent patients from further damage, which is crucial in treating AD. Over the past few decades, it has been demonstrated that neuroimaging can be a critical diagnostic tool for AD, and the feature fusion of different neuroimaging modalities can enhance diagnostic performance. Most previous studies in multimodal feature fusion have only concatenated the high-level features extracted by neural networks from various neuroimaging images simply. However, a major problem of these studies is over-looking the low-level feature interactions between modalities in the feature extraction stage, resulting in suboptimal performance in AD diagnosis. In this paper, we develop a dual-branch vision transformer with cross-attention and graph pooling, namely CsAGP, which enables multi-level feature interactions between the inputs to learn a shared feature representation. Specifically, we first construct a brand-new cross-attention fusion module (CAFM), which processes MRI and PET images by two independent branches of differing computational complexity. These features are fused merely by the cross-attention mechanism to enhance each other. After that, a concise graph pooling algorithm-based Reshape-Pooling-Reshape (RPR) framework is developed for token selection to reduce token redundancy in the proposed model. Extensive experiments on the Alzheimer's Disease Neuroimaging Initiative (ADNI) database demonstrated that the suggested method obtains 99.04%, 97.43%, 98.57%, and 98.72% accuracy for the classification of AD vs. CN, AD vs. MCI, CN vs. MCI, and AD vs. CN vs. MCI, respectively.

An embedded interfacial network stabilizes inorganic CsPbI3 perovskite thin films.

The black perovskite phase of CsPbI3 is promising for optoelectronic applications; however, it is unstable under ambient conditions, transforming within minutes into an optically inactive yellow phase, a fact that has so far prevented its widespread adoption. Here we use coarse photolithography to embed a PbI2-based interfacial microstructure into otherwise-unstable CsPbI3 perovskite thin films and devices. Films fitted with a tessellating microgrid are rendered resistant to moisture-triggered decay and exhibit enhanced long-term stability of the black phase (beyond 2.5 years in a dry environment), due to increasing the phase transition energy barrier and limiting the spread of potential yellow phase formation to structurally isolated domains of the grid. This stabilizing effect is readily achieved at the device level, where unencapsulated CsPbI3 perovskite photodetectors display ambient-stable operation. These findings provide insights into the nature of phase destabilization in emerging CsPbI3 perovskite devices and demonstrate an effective stabilization procedure which is entirely orthogonal to existing approaches.

Dipole Engineering through the Orientation of Interface Molecules for Efficient InP Quantum Dot Light-Emitting Diodes.

InP-based quantum dot (QD) light-emitting diodes (QLEDs) provide a heavy-metal-free route to size-tuned LEDs having high efficiency. The stability of QLEDs may be enhanced by replacing organic hole-injection layers (HILs) with inorganic layers. However, inorganic HILs reported to date suffer from inefficient hole injection, the result of their shallow work functions. Here, we investigate the tuning of the work function of nickel oxide (NiOx) HILs using self-assembled molecules (SAMs). Density functional theory simulations and near-edge X-ray absorption fine structure put a particular focus onto the molecular orientation of the SAMs in tuning the work function of the NiOx HIL. We find that orientation plays an even stronger role than does the underlying molecular dipole itself: SAMs having the strongest electron-withdrawing nitro group (NO2), despite having a high intrinsic dipole, show limited work function tuning, something we assign to their orientation parallel to the NiOx surface. We further find that the NO2 group─which delocalizes electrons over the molecule by resonance─induces a deep lowest unoccupied molecular orbital level that accepts electrons from QDs, producing luminescence quenching. In contrast, SAMs containing a trifluoromethyl group exhibit an angled orientation relative to the NiOx surface, better activating hole injection into the active layer without inducing luminescence quenching. We report an external quantum efficiency (EQE) of 18.8%─the highest EQE among inorganic HIL-based QLEDs (including Cd-based QDs)─in InP QLEDs employing inorganic HILs.

Germanium silicon oxide achieves multi-coloured ultra-long phosphorescence and delayed fluorescence at high temperature.

Colour-tuned phosphors are promising for advanced security applications such as multi-modal anti-counterfeiting and data encryption. The practical adoption of colour-tuned phosphors requires these materials to be responsive to multiple stimuli (e.g., excitation wavelength, excitation waveform, and temperature) and exhibit excellent materials stability simultaneously. Here we report germanium silicon oxide (GSO) - a heavy-metal-free inorganic phosphor - that exhibits colour-tuned ultra-long phosphorescence and delayed fluorescence across a broad temperature range (300 - 500 K) in air. We developed a sol-gel processing strategy to prepare amorphous oxides containing homogeneously dispersed Si and Ge atoms. The co-existence of Ge and Si luminescent centres (LC) leads to an excitation-dependent luminescence change across the UV-to-visible region. GSO exhibits Si LC-related ultra-long phosphorescence at room-temperature and thermally activated delayed fluorescence at temperatures as high as 573 K. This long-lived PL is sensitized via the energy transfer from Ge defects to Si LCs, which provides PL lifetime tunability for GSO phosphors. The oxide scaffold of GSO offers 500-day materials stability in air; and 1-week stability in strong acidic and basic solutions. Using GSO/polymer hybrids, we demonstrated colour-tuned security tags whose emission wavelength and lifetime can be controlled via the excitation wavelength, and temperature, indicating promise in security applications.

All-perovskite tandem solar cells with improved grain surface passivation.

All-perovskite tandem solar cells hold the promise of surpassing the efficiency limits of single-junction solar cells1-3; however, until now, the best-performing all-perovskite tandem solar cells have exhibited lower certified efficiency than have single-junction perovskite solar cells4,5. A thick mixed Pb-Sn narrow-bandgap subcell is needed to achieve high photocurrent density in tandem solar cells6, yet this is challenging owing to the short carrier diffusion length within Pb-Sn perovskites. Here we develop ammonium-cation-passivated Pb-Sn perovskites with long diffusion lengths, enabling subcells that have an absorber thickness of approximately 1.2 µm. Molecular dynamics simulations indicate that widely used phenethylammonium cations are only partially adsorbed on the surface defective sites at perovskite crystallization temperatures. The passivator adsorption is predicted to be enhanced using 4-trifluoromethyl-phenylammonium (CF3-PA), which exhibits a stronger perovskite surface-passivator interaction than does phenethylammonium. By adding a small amount of CF3-PA into the precursor solution, we increase the carrier diffusion length within Pb-Sn perovskites twofold, to over 5 µm, and increase the efficiency of Pb-Sn perovskite solar cells to over 22%. We report a certified efficiency of 26.4% in all-perovskite tandem solar cells, which exceeds that of the best-performing single-junction perovskite solar cells. Encapsulated tandem devices retain more than 90% of their initial performance after 600 h of operation at the maximum power point under 1 Sun illumination in ambient conditions.

Integrative analyses of geochemical parameters-microbe interactions reveal the variation of bacterial community assembly in multiple metal(loid)s contaminated arable regions.

Soil microbes play crucial roles in biochemical and geochemical processes in contaminated arable ecosystems. However, what factors determine the assembling process of soil bacterial community under multiple heavy metal (loid)s (HMs) stress and how communities respond to geochemical changes have rarely been understood. Therefore, a number of contaminated soils were sampled to explore the interactions among geochemical parameters, HMs and innate bacterial community. The results showed that soil biochemical activities were inhibited obviously with the increase of HMs. Significant differences were observed in bacterial composition and abundance in studied areas, with Actinobacteria, Proteobacteria, Chloroflexi, Acidobacteria and Firmicutes governing the bacterial community structure. Redundancy analysis and variation partition analysis revealed that about 67.33% of the variation in bacterial assemblages could be explained by physiochemical parameters (21.59%), biochemical parameters (11.64%), toxic metal (loid)s (9.11%) and the interaction effect of these variables (24.99%), among which total-arsenic and moisture were the main factors. Spearman correlation analysis also demonstrated that dehydrogenase, moisture and TOC have a positive correlation with bacterial community structure with As-Cd-Pb gradient. Altogether, this study would provide a comprehensive relationship between major environmental factors and bacterial assemblages, which could offer some baseline data to investigate the mechanisms of how communities respond to physiochemical changes.

Magnolol attenuates the locomotor impairment, cognitive deficit, and neuroinflammation in Alzheimer's disease mice with brain insulin resistance via up-regulating miR-200c.

In this study, we aimed to investigate the effect of Magnolol on Alzheimer's disease (AD). After the model of streptozotocin-induced AD mice with brain insulin resistance was established, the mice were treated with Magnolol or miR-200c antagomiR. The abilities of ambulations, rearings, discrimination, spatial learning, and memory were evaluated by open-field test (OFT), novel object recognition (NOR), and morris water maze (MWM) tests. The levels of malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), C-reactive protein (CRP), and miR-200c in the mice hippocampus were evaluated by enzyme-linked immunosorbent assay, Western blot, or Quantitative real-time Polymerase Chain Reaction. In AD mice model, streptozotocin induced the locomotor impairment and cognitive deficit, up-regulated levels of MDA, TNF-α, IL-6, and CRP, while down-regulated levels of GSH, SOD, and miR-200c. Magnolol increased the rearings numbers and discrimination index of AD mice in OFT and NOR tests. Magnolol increased the number of entries in the target quadrant and time spent in the target quadrant and decreased the escape latency of AD mice in the MWM test. Magnolol also down-regulated the levels of MDA, TNF-α, IL-6, and CRP, and up-regulated the levels of GSH, SOD, and miR-200c in the hippocampus tissues of AD mice. However, miR-200c antagomiR did the opposite and further offset the effects of the Magnolol on AD mice. Magnolol attenuated the locomotor impairment, cognitive deficit, and neuroinflammatory in AD mice with brain insulin resistance via up-regulating miR-200c.

Effects of Radial Extracorporeal Shock Wave Therapy on Flexor Spasticity of the Upper Limb in Post-stroke Patients: Study Protocol for a Randomized Controlled Trial.

Background: Flexor spasticity of the upper limb is common in poststroke patients and seriously affects the recovery of upper limb function. However, there are no standard management protocols for this condition. Radial extracorporeal shock wave therapy (rESWT) is widely used for various diseases, some studies reported the effects of ESWT on reducing spasticity, but the mechanism of ESWT to reduce spasticity by affecting the excitability of stretch reflex or non-neural rheological components in spastic muscles or both is not yet clear. A large randomized controlled trial with comprehensive evaluation indicators is still needed. The study is to observe the effect of rESWT on flexor spasticity of the upper limb after stroke and explore its mechanism. Methods: A prospective, randomized, double-blind controlled trial is to be performed. One hundred participants will be recruited from the Inpatient Department of Zhujiang Hospital. Eligible patients will be randomly allocated to either receive three sessions of active rESWT (group A) or sham-placebo rESWT (group B) with 3-day intervals between each session. Assessment will be performed at baseline and at 24 h after each rESWT (t1, t2, and t3). The primary assessment outcome will be the Modified Ashworth Scale, and other assessments include surface electromyography, MyotonPRO digital muscle function evaluation, and infrared thermal imaging. All data will be analyzed using intention-to-treat principles. Multiple imputation by chained equations will be used to address missing data caused by loss to follow-up and nonresponses. Per protocol, analyses will also be performed on the participants who complete other assessments. Statistical analysis will be performed using SPSS software (version 20.0) and the significance level set at p < 0.05. Discussion: This trial aims to analyze the application of rESWT for the management of spasticity after stroke via appropriate assessments. We hypothesized that after receiving active rESWT, patients would show greater improvement of upper limb muscles compared with patients within the sham-placebo group. The rESWT would be an alternative to traditional methods, and the results of this study may provide support for the further study of potential mechanisms. Clinical Trial Registration:www.chictr.org.cn, identifier: ChiCTR1800016144.

One-Step Synthesis of SnI2·(DMSO)x Adducts for High-Performance Tin Perovskite Solar Cells.

Contemporary thin-film photovoltaic (PV) materials contain elements that are scarce (CIGS) or regulated (CdTe and lead-based perovskites), a fact that may limit the widespread impact of these emerging PV technologies. Tin halide perovskites utilize materials less stringently regulated than the lead (Pb) employed in mainstream perovskite solar cells; however, even today's best tin-halide perovskite thin films suffer from limited carrier diffusion length and poor film morphology. We devised a synthetic route to enable in situ reaction between metallic Sn and I2 in dimethyl sulfoxide (DMSO), a reaction that generates a highly coordinated SnI2·(DMSO)x adduct that is well-dispersed in the precursor solution. The adduct directs out-of-plane crystal orientation and achieves a more homogeneous structure in polycrystalline perovskite thin films. This approach improves the electron diffusion length of tin-halide perovskite to 290 ± 20 nm compared to 210 ± 20 nm in reference films. We fabricate tin-halide perovskite solar cells with a power conversion efficiency of 14.6% as certified in an independent lab. This represents a ∼20% increase compared to the previous best-performing certified tin-halide perovskite solar cells. The cells outperform prior earth-abundant and heavy-metal-free inorganic-active-layer-based thin-film solar cells such as those based on amorphous silicon, Cu2ZnSn(S/Se)4 , and Sb2(S/Se)3.

Facet-Oriented Coupling Enables Fast and Sensitive Colloidal Quantum Dot Photodetectors.

Charge carrier transport in colloidal quantum dot (CQD) solids is strongly influenced by coupling among CQDs. The shape of as-synthesized CQDs results in random orientational relationships among facets in CQD solids, and this limits the CQD coupling strength and the resultant performance of optoelectronic devices. Here, colloidal-phase reconstruction of CQD surfaces, which improves facet alignment in CQD solids, is reported. This strategy enables control over CQD faceting and allows demonstration of enhanced coupling in CQD solids. The approach utilizes post-synthetic resurfacing and unites surface passivation and colloidal stability with a propensity for dots to couple via (100):(100) facets, enabling increased hole mobility. Experimentally, the CQD solids exhibit a 10× increase in measured hole mobility compared to control CQD solids, and enable photodiodes (PDs) exhibiting 70% external quantum efficiency (vs 45% for control devices) and specific detectivity, D* > 1012  Jones, each at 1550 nm. The photodetectors feature a 7 ns response time for a 0.01 mm2 area-the fastest reported for solution-processed short-wavelength infrared PDs.

Immobilization of cadmium by Burkholderia sp. QY14 through modified microbially induced phosphate precipitation.

Microbially induced phosphate precipitation (MIPP) is an advanced bioremediation technology to immobilize heavy metals. An indigenous bacterium QY14 with the function of mineralization isolated from Cd contaminated farmland soil was identified as Burkholderia ambifaria. The minimum inhibitory concentration value for QY14 was 550 mg/L for soluble Cd concentration. This study found that the addition of 10 mM Ca2+ during MIPP process could significantly increase the removal ratio of Cd, and the maximum removal ratio of Cd with 10 mM Ca2+ and without Ca2+ in solution was 99.97% and 76.14%, respectively. The increase of acid phosphatase activity and the formation of precipitate containing calcium caused by 10 mM Ca2+ addition contributed the increase of Cd removal efficiency. The results of SEM-EDS, FTIR and XRD showed that Cd was removed by forming Cd containing hydroxyapatite (Cd-HAP). In addition, the dissolution experiment showed the Cd release ratio of Cd-HAP (0.01‰ at initial pH 3.0 of solution) was lower than Cd-absorbed HAP, indicating that Cd was more likely removed by the formation of Ca10-xCdx(PO4)6(OH)2 solid solution. Our findings revealed MIPP-based bioremediation supplied with 10 mM Ca2+ could increase the Cd removal and could potentially be applied for Cd remediation.

Thiophene Cation Intercalation to Improve Band-Edge Integrity in Reduced-Dimensional Perovskites.

The insertion of large organic cations in metal halide perovskites with reduced-dimensional (RD) crystal structures increases crystal formation energy and regulates the growth orientation of the inorganic domains. However, the power conversion performance is curtailed by the insulating nature of the bulky cations. Now a series of RD perovskites with 2-thiophenmethylammonium (TMA) as the intercalating cation are investigated. Compared with traditional ligands, TMA demonstrates improved electron transfer in the inorganic framework. TMA modifies the near-band-edge integrity of the RD perovskite, improving hole transport. A power conversion efficiency of 19 % is achieved, the highest to date for TMA-based RD perovskite photovoltaics; these TMA devices provide a 12 % relative increase in PCE compared to control RD perovskite devices that use PEA as the intercalating ligand, a result of the improved charge transfer from the inorganic layer to the organic ligands.