[Retracted] miR­885­5p upregulation promotes colorectal cancer cell proliferation and migration by targeting suppressor of cytokine signaling.

[This retracts the article DOI: 10.3892/ol.2018.8645.].

Intracellular Zn2+ promotes extracellular matrix remodeling in dexamethasone-treated trabecular meshwork.

Given the widespread application of glucocorticoids in ophthalmology, the associated elevation of intraocular pressure (IOP) has long been a vexing concern for clinicians, yet the underlying mechanisms remain inconclusive. Much of the discussion focuses on the extracellular matrix (ECM) of trabecular meshwork (TM). It is widely agreed that glucocorticoids impact the expression of matrix metalloproteinases (MMPs), leading to ECM deposition. Since Zn2+ is vital for MMPs, we explored its role in ECM alterations induced by dexamethasone (DEX). Our study revealed that in human TM cells treated with DEX, the level of intracellular Zn2+ significantly decreased, accompanied by impaired extracellular Zn2+ uptake. This correlated with changes in several Zrt-, Irt-related proteins (ZIPs) and metallothionein. ZIP8 knockdown impaired extracellular Zn2+ uptake, but Zn2+ chelation did not affect ZIP8 expression. Resembling DEX's effects, chelation of Zn2+ decreased MMP2 expression, increased the deposition of ECM proteins, and induced structural disarray of ECM. Conversely, supplementation of exogenous Zn2+ in DEX-treated cells ameliorated these outcomes. Notably, dietary zinc supplementation in mice significantly reduced DEX-induced IOP elevation and collagen content in TM, thereby rescuing the visual function of the mice. These findings underscore zinc's pivotal role in ECM regulation, providing a novel perspective on the pathogenesis of glaucoma.NEW & NOTEWORTHY Our study explores zinc's pivotal role in mitigating extracellular matrix dysregulation in the trabecular meshwork and glucocorticoid-induced ocular hypertension. We found that in human trabecular meshwork cells treated with dexamethasone, intracellular Zn2+ significantly decreased, accompanied by impaired extracellular Zn2+ uptake. Zinc supplementation rescues visual function by modulating extracellular matrix proteins and lowering intraocular pressure, offering a direction for further exploration in glaucoma management.

Reduced Zn2+ promotes retinal ganglion cells survival and optic nerve regeneration after injury through inhibiting autophagy mediated by ROS/Nrf2.

The molecular mechanism of how reduced mobile zinc (Zn2+) affected retinal ganglion cell (RGC) survival and optic nerve regeneration after optic nerve crush (ONC) injury remains unclear. Here, we used conditionally knocked out ZnT-3 in the amacrine cells (ACs) of mice (CKO) in order to explore the role of reactive oxygen species (ROS), nuclear factor erythroid 2-related factor 2 (NFE2L2, Nrf2) and autophagy in the protection of RGCs and axon regeneration after ONC injury. We found that reduced Zn2+ can promote RGC survival and axonal regeneration by decreasing ROS, activating Nrf2, and inhibiting autophagy. Additionally, autophagy after ONC is regulated by ROS and Nrf2. Visual function in mice after ONC injury was partially recovered through the reduction of Zn2+, achieved by using a Zn2+ specific chelator N,N,N',N'-tetrakis-(2-Pyridylmethyl) ethylenediamine (TPEN) or through CKO mice. Overall, our data reveal the crosstalk between Zn2+, ROS, Nrf2 and autophagy following ONC injury. This study verified that TPEN or knocking out ZnT-3 in ACs is a promising therapeutic option for the treatment of optic nerve damage and elucidated the postsynaptic molecular mechanism of Zn2+-triggered damage to RGCs after ONC injury.

Thiazolo[5,4-d]thiazole-Based Metal-Organic Framework for Catalytic CO2 Cycloaddition and Photocatalytic Benzylamine Coupling Reactions.

Metal-organic frameworks (MOFs) with permanent porosity and multifunctional catalytic sites constructed by two or more organic ligands are regarded as effective heterogeneous catalysts to improve certain organic catalytic reactions. In this work, a pillared-layer Zn-MOF (MOF-LS10) was constructed by 2,3,5,6-tetrakis(4-carboxyphenyl)pyrazine (H4TCPP) and 2,5-di(pyridin-4-yl)thiazolo[5,4-d]thiazole (DPTZTZ). After activation, MOF-LS10 has a permanent porosity and moderate CO2 adsorption capacity. The introduction of thiazolo[5,4-d]thiazole (TZTZ), a photoactive unit, into the framework endows MOF-LS10 with excellent photocatalytic performance. MOF-LS10 can not only efficiently catalyze the formation of cyclic carbonates from CO2 and epoxide substrates under mild conditions but also can photocatalyze benzylamine coupling at room temperature. In addition, we used another two ligands 1,2,4,5-tetrakis(4-carboxyphenyl)benzene (H4BTEB) and 1,4-di(pyridin-4-yl)benzene (DPB) to synthesize MOF-LS11 (constructed by BTEB4- and DPTZTZ) and MOF-LS12 (constructed by TCPP4- and DPB) in order to explore whether the pyrazine structural unit and the TZTZ structural unit synergistically catalyze the reaction. The electron paramagnetic resonance spectrum demonstrates that the superoxide radical (·O2-), generated by electron transfer from the MOF excited by light to the oxidant, is the main active substance of oxidation. The design and synthesis of MOF-LS10 provide an effective synthetic strategy for the development of versatile heterogeneous catalysts for various organic reactions and a wide range of substrates.

Te-hybridized zeolitic imidazolate frameworks-derived core-shell design toward dendrite-free Zn anode for long-term aqueous zinc-ion batteries.

HYPOTHESIS: Aqueous zinc-ion batteries (AZIBs) have received considerable attention owing to their safety, low cost, and environmental benignity. However, the side reactions of hydrogen evolution revolution and Zn dendrite growth reduce the Coulombic efficiency and life span of AZIBs. To address these issues, we designed an artificial protective layer of a Te-hybridized core-shell zeolitic imidazolate framework (ZIF). EXPERIMENTS: A core-shell structure of ZIF-8@ZIF-67 was first developed as a protecting layer on the Zn anode. To improve the poor conductivity of ZIF and its affinity for Zn, the core-shell structure was hybridized with zincophilic Te to increase the surface area and reduce the charge-transfer resistance. FINDINGS: By incorporating metallic Te into ZIF-8 and ZIF-67, the nucleation potential and charge-transfer resistance were significantly reduced, enhancing the ion reaction kinetics and electron migration. Benefiting from the Te-hybridized ZIF-8@ZIF-67-derived nitrogen-doped porous carbon (Te-hybridized ZIF-8@ZIF-67/NC) layer, a full cell of Zn coated with Te-hybridized ZIF-8@ZIF-67/NC//MnO2 exhibited an excellent rate performance of 214 mAh g-1 at an ultrahigh current density of 10 A g-1 and ultralong cycle life (3200 cycles) without the formation of Zn dendrites.

Highly Crystalline Polyimide Covalent Organic Framework as Dual-Active-Center Cathode for High-Performance Lithium-Ion Batteries.

Polyimide covalent organic framework (PI-COF) materials that can realize intrinsic redox reactions by changing the charge state of their electroactive sites are considered as emerging electrode materials for rechargeable devices. However, the highly crystalline PI-COFs with hierarchical porosity are less reported due to the rapid reaction between monomers and the poor reversibility of the polyimidization reaction. Here, we developed a water-assistant synthetic strategy to adjust the reaction rate of polyimidization, and PI-COF (COFTPDA-PMDA) with kgm topology consisting of dual active centers of N,N,N',N'-tetrakis(4-aminophenyl)-1,4-benzenediamine (TPDA) and pyromellitic dianhydride (PMDA) ligands was successfully synthesized with high crystallinity and porosity. The COFTPDA-PMDA possesses hierarchical micro-/mesoporous channels with the largest surface area (2669 m2/g) in PI-COFs, which can promote the Li+ ions and bulky bis(trifluoromethanesulfonyl)imide (TFSI-) ions in organic electrolyte to sufficiently interact with the dual active sites on COF skeleton to increase the specific capacity of cathode materials. As a cathode material for lithium-ion batteries, COFTPDA-PMDA@50%CNT which integrated high surface area and dual active center of COFTPDA-PMDA with carbon nanotubes via π-π interactions gave a high initial charge capacity of 233 mAh/g (0.5 A/g) and maintains at 80 mAh/g even at a high current density of 5.0 A/g after 1800 cycles.

A graph network model for neural connection prediction and connection strength estimation.

Objective. Reconstruction of connectomes at the cellular scale is a prerequisite for understanding the principles of neural circuits. However, due to methodological limits, scientists have reconstructed the connectomes of only a few organisms such asC. elegans, and estimated synaptic strength indirectly according to their size and number.Approach. Here, we propose a graph network model to predict synaptic connections and estimate synaptic strength by using the calcium activity data fromC. elegans. Main results. The results show that this model can reliably predict synaptic connections in the neural circuits ofC. elegans, and estimate their synaptic strength, which is an intricate and comprehensive reflection of multiple factors such as synaptic type and size, neurotransmitter and receptor type, and even activity dependence. In addition, the excitability or inhibition of synapses can be identified by this model. We also found that chemical synaptic strength is almost linearly positively correlated to electrical synaptic strength, and the influence of one neuron on another is non-linearly correlated with the number between them. This reflects the intrinsic interaction between electrical and chemical synapses.Significance. Our model is expected to provide a more accessible quantitative and data-driven approach for the reconstruction of connectomes in more complex nervous systems, as well as a promising method for accurately estimating synaptic strength.

The improvement effect of astaxanthin-loaded emulsions on obesity is better than that of astaxanthin in the oil phase.

Emulsion-based delivery systems have been reported to improve the solubility, stability and bioavailability of astaxanthin. In this study, the ability of astaxanthin-loaded emulsions (AL) to ameliorate obesity induced by a high-fat and high-sucrose diet was explored, using astaxanthin in the oil phase (ASTA) as a comparison. After the administration of AL, ASTA (30 mg per kg body weight), or saline on normal or obese mice for 4 weeks, the body fat accumulation levels, hepatic lipid contents and hepatic fatty acid profiles were detected, and AL showed better anti-obesity properties than ASTA. In an acute feeding experiment, it was first observed that the astaxanthin concentration of AL was higher than that of ASTA in the blood and liver of obese mice. What's more, AL altered the microbial co-occurrence patterns in obese mice. Some gut microbial modules that were significantly correlated with obesity-related physiological parameters were identified. Overall, the improvement effect of AL on obesity is better than that of ASTA due to their higher oral absorbability and modulating effects on the gut microbiota, and we suggest AL as a more suitable astaxanthin product type for obese bodies.

Intercalation of Zinc Monochloride Cations by Deep Eutectic Solvents for High-Performance Rechargeable Non-aqueous Zinc Ion Batteries.

Zinc ion batteries have been extensively studied with an aqueous electrolyte system. However, the batteries suffer from a limited potential window, gas evolution, cathode dissolution, and dendrite formation on the anode. Considering these limitations, we developed an alternative electrolyte system based on deep eutectic solvents (DESs) because of their low cost, high stability, biodegradability, and non-flammability, making them optimal candidates for sustainable batteries. The DES electrolyte enables reversible Zn plating/stripping and effectively suppresses zinc dendrite formation. Furthermore, in-depth characterizations reveal that the energy storage mechanism can be attributed to [ZnCl]+ ion intercalation and the intermediate complex ion plays a pivotal role in electrochemical reactions, which deliver a high reversible capacity of 310 mAh g-1 at 0.1 A g-1and long-term stability (167 mAh g-1 at a current density of 0.3 A g-1 after 300 cycles, Coulombic efficiency: ∼98%). Overall, this work represents our new finding in rechargeable batteries with the DES electrolyte.

Frequency and Spectrum of Mutations Induced by Gamma Rays Revealed by Phenotype Screening and Whole-Genome Re-Sequencing in Arabidopsis thaliana.

Genetic variations are an important source of germplasm diversity, as it provides an allele resource that contributes to the development of new traits for plant breeding. Gamma rays have been widely used as a physical agent for mutation creation in plants, and their mutagenic effect has attracted extensive attention. However, few studies are available on the comprehensive mutation profile at both the large-scale phenotype mutation screening and whole-genome mutation scanning. In this study, biological effects on M1 generation, large-scale phenotype screening in M2 generation, as well as whole-genome re-sequencing of seven M3 phenotype-visible lines were carried out to comprehensively evaluate the mutagenic effects of gamma rays on Arabidopsis thaliana. A total of 417 plants with visible mutated phenotypes were isolated from 20,502 M2 plants, and the phenotypic mutation frequency of gamma rays was 2.03% in Arabidopsis thaliana. On average, there were 21.57 single-base substitutions (SBSs) and 11.57 small insertions and deletions (InDels) in each line. Single-base InDels accounts for 66.7% of the small InDels. The genomic mutation frequency was 2.78 × 10-10/bp/Gy. The ratio of transition/transversion was 1.60, and 64.28% of the C > T events exhibited the pyrimidine dinucleotide sequence; 69.14% of the small InDels were located in the sequence with 1 to 4 bp terminal microhomology that was used for DNA end rejoining, while SBSs were less dependent on terminal microhomology. Nine genes, on average, were predicted to suffer from functional alteration in each re-sequenced line. This indicated that a suitable mutation gene density was an advantage of gamma rays when trying to improve elite materials for one certain or a few traits. These results will aid the full understanding of the mutagenic effects and mechanisms of gamma rays and provide a basis for suitable mutagen selection and parameter design, which can further facilitate the development of more controlled mutagenesis methods for plant mutation breeding.

Generalized optical design and optimization of multipass cells with independent circle patterns based on the Monte Carlo and Nelder-Mead simplex algorithms.

In this paper, we propose an automatic approach to optimize the multipass cell (MPC) design with independent circle patterns. First, the Monte Carlo algorithm is performed to globally search for the characteristic values of the distance between two mirrors. Second, the Nelder-Mead simplex (NM) algorithm is applied to locally optimize the re-entry condition. In addition, we utilize the clustering method to select the independent circle patterns automatically. Three optimal MPCs with five, seven and nine independent circles are built and tested experimentally. We analyze the stability of the final point for the MPCs and optimize the quality of the output beam based on multi-ray tracing. This type of MPC shows the superior characteristics of compactness, high detection sensitivity, and affordability, has various applications, and can promote the development of portable gas sensors. The proposed approach is effective and efficient for automatically optimizing MPC design and can be further extended to versatile optical designs.

Genetic Variants of the MIF Gene and Susceptibility of Rectal Cancer.

BACKGROUND: Rectal cancer (RC) has been documented to be a highly invasive malignant neoplasm worldwide. Macrophage migration inhibitory factor (MIF) is a multifunctional cytokine involved in cell-mediated immunity, immunoregulation, inflammation. In vitro and in vivo studies have identified that MIF was involved in the carcinogenesis and progression of RC. PATIENTS AND METHODS: This case-control study evaluated associations of genetic variants of the MIF gene and serum level of MIF with susceptibility of RC. RESULTS: We found MIF level was associated with an increased risk of RC (OR for per unit: 1.38, 95% CI:1.32-1.44; P < 0.001). Both MIF rs2012133 (OR = 1.30; 95% CIs = 1.08-1.58; P = 0.007) and rs755622 (OR = 1.45; 95% CIs = 1.15-1.82; P = 0.002) were significantly associated with increased risk of RC. Besides, we also found MIF rs5844572 was significantly associated with increased susceptibility of RC, with OR for per CATT repeat of 1.28 (95% CIs: 1.16-1.41; P < 0.001). Further, we found all three variants of the MIF gene, rs5844572, rs2012133 and rs755622, could increase serum level of MIF. CONCLUSION: This study suggests that MIF plays an important role in the carcinogenesis of RC and could be used as a biomarker for early detection and prediction of RC.

Design of Core-Shell Quantum Dots-3D WS2 Nanowall Hybrid Nanostructures with High-Performance Bifunctional Sensing Applications.

Transition metal dichalcogenides (TMDCs) have recently attracted a tremendous amount of attention owing to their superior optical and electrical properties as well as the interesting and various nanostructures that are created by different synthesis processes. However, the atomic thickness of TMDCs limits the light absorption and results in the weak performance of optoelectronic devices, such as photodetectors. Here, we demonstrate the approach to increase the surface area of TMDCs by a one-step synthesis process of TMDC nanowalls from WOx into three-dimensional (3D) WS2 nanowalls. By utilizing a rapid heating and rapid cooling process, the formation of 3D nanowalls with a height of approximately 150 nm standing perpendicularly on top of the substrate can be achieved. The combination of core-shell colloidal quantum dots (QDs) with three different emission wavelengths and 3D WS2 nanowalls further improves the performance of WS2-based photodetector devices, including a photocurrent enhancement of 320-470% and shorter response time. The significant results of the core-shell QD-WS2 hybrid devices can be contributed by the high nonradiative energy transfer efficiency between core-shell QDs and the nanostructured material, which is caused by the spectral overlap between the emission of core-shell QDs and the absorption of WS2. Besides, outstanding NO2 gas-sensing performance of core-shell QDs/WS2 devices can be achieved with an extremely low detection limit of 50 ppb and a fast response time of 26.8 s because of local p-n junctions generated by p-type 3D WS2 nanowalls and n-type core-shell CdSe-ZnS QDs. Our work successfully reveals the energy transfer phenomenon in core-shell QD-WS2 hybrid devices and shows great potential in commercial multifunctional sensing applications.

Three-Dimensional Molybdenum Diselenide Helical Nanorod Arrays for High-Performance Aluminum-Ion Batteries.

The rechargeable aluminum-ion battery (AIB) is a promising candidate for next-generation high-performance batteries, but its cathode materials require more development to improve their capacity and cycling life. We have demonstrated the growth of MoSe2 three-dimensional helical nanorod arrays on a polyimide substrate by the deposition of Mo helical nanorod arrays followed by a low-temperature plasma-assisted selenization process to form novel cathodes for AIBs. The binder-free 3D MoSe2-based AIB shows a high specific capacity of 753 mAh g-1 at a current density of 0.3 A g-1 and can maintain a high specific capacity of 138 mAh g-1 at a current density of 5 A g-1 with 10 000 cycles. Ex situ Raman, XPS, and TEM characterization results of the electrodes under different states confirm the reversible alloying conversion and intercalation hybrid mechanism during the discharge and charge cycles. All possible chemical reactions were proposed by the electrochemical curves and characterization. Further exploratory works on interdigital flexible AIBs and stretchable AIBs were demonstrated, exhibiting a steady output capacity under different bending and stretching states. This method provides a controllable strategy for selenide nanostructure-based AIBs for use in future applications of energy-storage devices in flexible and wearable electronics.

High-Performance Rechargeable Aluminum-Selenium Battery with a New Deep Eutectic Solvent Electrolyte: Thiourea-AlCl3.

Aluminum-sulfur batteries (ASBs) have attracted substantial interest due to their high theoretical specific energy density, low cost, and environmental friendliness, while the traditional sulfur cathode and ionic liquid have very fast capacity decay, limiting cycling performance because of the sluggishly electrochemical reaction and side reactions with the electrolyte. Herein, we demonstrate, for the first time, excellent rechargeable aluminum-selenium batteries (ASeBs) using a new deep eutectic solvent, thiourea-AlCl3, as an electrolyte and Se nanowires grown directly on a flexible carbon cloth substrate (Se NWs@CC) by a low-temperature selenization process as a cathode. Selenium (Se) is a chemical analogue of sulfur with higher electronic conductivity and lower ionization potential that can improve the battery kinetics on the sluggishly electrochemical reaction and the reduction of the polarization where the thiourea-AlCl3 electrolyte can stabilize the side reaction during the reversible conversion reaction of Al-Se alloying processes during the charge-discharge process, yielding a high specific capacity of 260 mAh g-1 at 50 mA g-1 and a long cycling life of 100 times with a high Coulombic efficiency of nearly 93% at 100 mA g-1. The working mechanism based on the reversible conversion reaction of the Al-Se alloying processes, confirmed by the ex situ Raman, XRD, and XPS measurements, was proposed. This work provides new insights into the development of rechargeable aluminum-chalcogenide (S, Se, and Te) batteries.

LncRNA MIR503HG is downregulated in Han Chinese with colorectal cancer and inhibits cell migration and invasion mediated by TGF-ß2.

In this study we investigated the role of lncRNA MIR503HG in colorectal cancer (CRC). We found that MIR503HG was downregulated and TGF-ß2 was upregulated in CRC included in this study. Low levels of MIR503HG were associated with poor survival of CRC patients within 5 years after admission. MIR503HG and TGF-ß2 were inversely correlated in CRC tissues, and in CRC cells, MIR503HG overexpression was accompanied by TGF-ß2 downregulation, while TGF-ß2 overexpression did not affect MIR503HG. TGF-ß2 overexpression mediated the increased migration and invasion rates of CRC cells. MIR503HG overexpression mediated the decreased migration and invasion rates of CRC cells. Moreover, TGF-ß2 overexpression reduced the effects of MIR503HG overexpression. Therefore, MIR503HG overexpression inhibits CRC cell migration and invasion mediated by TGF-ß2.

3D CoMoSe4 Nanosheet Arrays Converted Directly from Hydrothermally Processed CoMoO4 Nanosheet Arrays by Plasma-Assisted Selenization Process Toward Excellent Anode Material in Sodium-Ion Battery.

In this work, three-dimensional (3D) CoMoSe4 nanosheet arrays on network fibers of a carbon cloth denoted as CoMoSe4@C converted directly from CoMoO4 nanosheet arrays prepared by a hydrothermal process followed by the plasma-assisted selenization at a low temperature of 450 °C as an anode for sodium-ion battery (SIB) were demonstrated for the first time. With the plasma-assisted treatment on the selenization process, oxygen (O) atoms can be replaced by selenium (Se) atoms without the degradation on morphology at a low selenization temperature of 450 °C. Owing to the high specific surface area from the well-defined 3D structure, high electron conductivity, and bi-metal electrochemical activity, the superior performance with a large sodium-ion storage of 475 mA h g-1 under 0.5-3 V potential range at 0.1 A g-1 was accomplished by using this CoMoSe4@C as the electrode. Additionally, the capacity retention was well maintained over 80 % from the second cycle, exhibiting a satisfied capacity of 301 mA h g-1 even after 50 cycles. The work delivered a new approach to prepare a binary transition metallic selenide and definitely enriches the possibilities for promising anode materials in SIBs with high performances.

An indoor light-activated 3D cone-shaped MoS2 bilayer-based NO gas sensor with PPb-level detection at room-temperature.

Utilization of light to boost the performance of gas sensors allows us to operate sensor devices at room temperature. Here, we, for the first time, demonstrated an indoor light-activated 3D cone-shaped MoS2 bilayer-based NO gas sensor with ppb-level detection operated at room-temperature. Large-area cone-shaped (CS)-MoS2 bilayers were grown by depositing 2 nm-thick MoO3 layers on a 2'' three-dimensional (3D) cone-patterned sapphire substrate (CPSS) followed by a sulfurization process via chemical vapor deposition. Because the exposed area of MoS2 bilayers is increased by 30%, the CS-MoS2 gas sensor (GS) demonstrated excellent performance with a response of ∼470% and a fast response time of ∼25 s after exposure to 1 ppm of NO gas illuminated by ultraviolet (UV) light with a wavelength of 365 nm. Such extraordinary performance at room temperature is attributed to the enhanced light absorption because of the light scattering effect caused by the 3D configuration and photo-desorption induced by UV illumination. For NO concentrations ranging from 2 ppm down to 0.06 ppm, the CS-MoS2 GS demonstrated a stable sensing behavior with a high response and fast response time (470% and 25 s at 2 ppm NO) because of the light absorption enhanced by the 3D structure and photo-desorption under constant UV illumination. The CS-MoS2 GS exhibits a high sensitivity (∼189.2 R% ppm-1), allowing the detection of NO gas at 0.06 ppm in 130 s. In addition, the 3D cone-shaped structure prolonged the presence of sulfur vapor around MoO3, allowing MoO3 to react with sulfur completely. Furthermore, the CS-MoS2 GS using an indoor lighting to detect NO gas at room temperature was demonstrated for the first time where the CS-MoS2 GS exhibits a stable cycling behavior with a high response (165% at 1 ppm NO) in 50 s; for concentration as low as ∼0.06 ppm, the response of ∼75% in 150 s can be achieved.

Europium functionalized silicon quantum dots nanomaterials for ratiometric fluorescence detection of Bacillus anthrax biomarker.

Bacillus anthracis spore causes anthrax to seriously threaten human health and even cause death. 2,6-Pyridinedicarboxylic acid (DPA) is a unique biomarker because it is a major component of Bacillus anthracis spore. Herein, we design europium functionalized silicon quantum dots as a ratiometric fluorescent nanoprobe to detect DPA with high sensitivity and selectivity. With the addition of DPA, the red emission peaks were observed at 618 nm. The novel probe enables ratiometric and sensitive DPA detection over nanomolar concentrations (as low as 1.02 µM). This work provided an efficient background-free and self-calibrating method for the recognition of DPA.

Few-Layer Graphene Sheet-Passivated Porous Silicon Toward Excellent Electrochemical Double-Layer Supercapacitor Electrode.

Few-layer graphene sheet-passivated porous silicon (PSi) as an outstanding electrochemical double-layer supercapacitor electrode was demonstrated. The PSi matrix was formed by electrochemical etching of a doped silicon wafer and was further surface-passivated with few-layer graphene sheets by a Ni-assisted chemical vapor deposition process where a wide range of porous PSi structures, including mesoporous, macroporous, and hybrid porous structures were created during the graphene growth as temperature increases. The microstructural and graphene-passivation effects on the capacitive performance of the PSi were investigated in detail. The hybrid porous PSi electrode, optimized in terms of capacitive performances, achieves a high areal capacitance of 6.21 mF/cm2 at an ultra-high scan rate of 1000 mV/s and an unusual progressing cyclic stability of 131% at 10,000 cycles. Besides mesopores and macropores, micropores were introduced onto the surfaces of the passivating few-layer graphene sheets with a KOH activation process to further increase the functioning surface area of the hierarchical porous PSi electrode, leading to a boost in the areal capacitance by 31.4% up to 8.16 mF/cm2. The present designed hierarchical porous PSi-based supercapacitor proves to be a robust energy storage device for microelectronic applications that require stable high rate capability.