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Herein, a scheme of Sr2+/Ca2+ ion substitution was employed to simultaneously regulate the defect and intervalence charge transfer (IVCT) state of Sr2−xCaxNb2O7:Pr3+ phosphors, resulting in a dual-modulation strategy for enhancing phosphor thermal stability. [ABSTRACT FROM AUTHOR]

Praseodymium (Pr3+) ion and the transition metal vanadium (V5+) ion with d0 electronic configuration can form an intervalence charge transfer (IVCT) band, which can function both as a compensatory channel for its red emission and as a quenching channel, thus affecting the luminescence thermal stability of the phosphors. Research studies reveal that the emission of Pr3+ in the YVO4 matrix can be quenched by the IVCT mechanism, thereby limiting the application of phosphors. As such, the present contribution is based on the solid solution replacement strategy to inhibit the constitutent of the IVCT quenching channel and thus improve thermal stability. Therefore, phosphonium (P5+) with a valence state matching V5+ and a similar ion radius was selected for the V/P substitution. It lacks a d0 electron configuration, preventing the formation of an IVCT band with Pr3+ and thereby inhibiting the construction of the quenching channels to enhance thermal stability. While the empirical formula of IVCT indicates a decrease in the IVCT energy level from 3.32438 to 3.06251 eV upon the introduction of P5+, the PLE spectra demonstrate a sharp reduction in IVCT intensity, i.e., weakening of the quenching channel. The thermal stability of the phosphors at different excitation locations was enhanced with the rise of P5+ concentration. When excited at the 3P2 level, the Y0.995PO4:0.5%Pr3+ phosphor demonstrated highly stable red emission from 303 to 523 K, with a luminescence integrated intensity ranging from 95.5% to 105.3% compared to that at 303 K. This research provides a novel approach for inhibiting the IVCT quenching channel and broadens the commercial value of YVO4:Pr3+ phosphor for various applications. [ABSTRACT FROM AUTHOR]

Water splitting is considered as a promising technology to solve energy shortage and environmental pollution. Since oxygen evolution reaction (OER) directly affects the efficiency of hydrogen evolution, the preparation of efficient and inexpensive OER catalysts is an urgent problem. "Low‐temperature immersion" (LTI) is expected to be a prospective strategy for electrocatalyst preparation due to its simplicity and energy‐saving advantages. However, there is almost no comprehensive overview on the progress of LTI engineering in the construction of non‐precious metal self‐supported electrocatalysts for OER. Herein, this review firstly introduces the principles and applications of LTI engineering‐assisted preparation of non‐precious metal self‐supported electrocatalysts in terms of etching and deposition. Then the mechanism of OER is analyzed from an amorphous viewpoint, and finally some perspective insights and future challenges of this method are discussed. [ABSTRACT FROM AUTHOR]

Non-noble metal for surface plasmon resonance (SPR)-induced nano-enzymatic photoelectrochemical (PEC) biosensors is a promising method for broad applications. Non-noble metal bismuth (Bi) is gradually being valued for their properties such as non-toxicity, abundant reserves, and good catalysis. Meanwhile, metallic Bi nanoparticles (NPs) have superior SPR properties similar to that of noble metal. Therefore, a non-noble metal Bi/BiVO4 photoanode based on SPR was designed for the PEC detection of H2O2 in this work. The synergistic effect of BiVO4 with suitable band gap (2.5 eV) and Bi NPs with superior SPR effectively reduces the recombination of photogenerated electrons and holes, which significantly improves the PEC activity of Bi/BiVO4 electrode at low voltage. The in situ Bi/BiVO4/FTO photoelectrode not only exhibits a more comprehensive linear range of 0.005–2.6 mM with a lower detection limit of 2.0 μM but also possesses excellent selectivity for the determination of H2O2 because the coexisting substances are difficult to be oxidized at 0 V bias voltage. The investigation of Bi/BiVO4-based sensor has contributed to the development of non-noble metal for SPR-induced PEC biosensors. [ABSTRACT FROM AUTHOR]

Bismuth (Bi) is a particular element with many distinctive properties such as low toxicity or nontoxicity, high specific gravity, photoluminescence, photoelectronic and photovoltaic effects, strong oxidation ability, water insolubility, etc. These distinctive properties help to boost various applications of Bi. The recent decades have witnessed a dramatic increase in the application research of Bi‐based materials, especially on photocatalysis. This paper begins with an introduction to the history of Bi, followed by a summary of its distinctive properties, and then provides a comprehensive overview of its applications in photocatalysis, sensing, medicine, and diagnosis and treatments, with a particular focus on near‐infrared photocatalysis, flexible wearable sensor, in vivo detection and therapeutics. Finally, the main challenges and development prospects of the Bi‐based materials are introduced. With the development trends of Bi research discussed, this paper is aimed at improving the knowledge of Bi and arising the research interest of Bi in the hope of extending the applications of Bi. [ABSTRACT FROM AUTHOR]

The synthesis conditions of most phosphors doped with lanthanide ions with d–f transition require a reducing atmosphere. The doping Bi3+ ions selected in this study perfectly avoid this requirement, and they are environmentally friendly and safe. Nevertheless, the spectral tuning of Bi3+ is a great challenge that limits its application. Herein, by regulating the value of x in the new solid solution Sr2+xLa1−xGaO5−xFx, the luminescence of Bi3+ is well promoted. Through an excitation-driven strategy, the emission peak position of Bi3+ is redshifted, and the luminescence of trivalent bismuth is successfully adjusted, which can also be applied to anti-blue lighting. In addition, we constructed a Bi3+–Eu3+ dual luminescence system, and, regardless of changes in the Bi3+/Eu3+ concentration or excitation wavelength, a single matrix white light phosphor was realized. Through calculations, the activation energy of the phosphor doped with 2.5%Eu3+ was found to be 0.257 eV, which is higher than the activation energy of some common compounds. This indicates that the phosphor has good application prospects in the field of solid-state lighting. It is worth noting that based on the different thermal response behaviors of Bi3+ and Eu3+, when the Eu3+ content is fixed at 1%, the maximum relative sensitivity of the optical thermometer based on its fluorescence intensity ratio is about 1.46% K−1 at 383 K, which is higher than that of Bi3+ and Eu3+ co-doped phosphors previously reported. We also obtained a high absolute sensitivity of 0.00139 K−1 at 403 K. Therefore, we also studied the thermal sensitivity of Bi3+ and Er3+ co-doped solid solutions. The results show that this solid-solution phosphor has far-reaching application prospects in the temperature sensing field. [ABSTRACT FROM AUTHOR]

Most praseodymium-doped red-emitting phosphors need high-temperature synthesis conditions with a reducing atmosphere. The niobate matrix selected in this work provides a sufficient electron-rich-site environment for praseodymium through charge migration, and praseodymium can be self-reduced in air atmosphere, which is safe and environmentally friendly. By building the [NbO6] group → Pr3+ energy transfer and finely modifying the doping concentration of Pr3+ ions, we constructed a dual-luminescence-system of the [NbO6] group and Pr3+. Thereby, optical temperature measurement based on fluorescence intensity ratio (FIR) technology of Pr3+ ions and [NbO6] groups was carried out using non-thermal coupling pairs, through the Boltzmann fitting and integral calculation, the maximum Sr and Sa values were 2.25% K−1 and 0.0049 K−1 at 403 K and 443 K, respectively, the Sr value is four times that obtained from the thermal coupling of Pr3+ ions, which exceeded most values previously reported for the fluorescence powder. Accordingly, we also studied the thermal sensitivity of Er3+ ions and Eu3+ ions mono-doped CaNb2O6 substrates. Results reveal that CaNb2O6:Pr3+/Er3+/Eu3+ phosphors have splendid temperature sensitivity and have far-reaching application prospects in the field of temperature measurements. [ABSTRACT FROM AUTHOR]

In2S3/BiOI composites were synthesized at room temperature which significantly improved the photocatalytic degradation of tetracycline hydrochloride (TC) under visible light irradiation. Structure and morphology characterization techniques have been performed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction measurements (XRD) and X-ray photoelectron spectra (XPS). The separation ability of photogenerated carriers is enhanced due to the formation of heterojunctions of the composites. The best performance is obtained when the content of In2S3 is 7 wt%. Compared with In2S3 and BiOI alone, 7-In2S3/BiOI has the highest specific surface area and can provide more active sites. Based on the photo-electrochemical characterization and free radical tests, a photocatalytic mechanism of In2S3/BiOI composites in the presence of superoxide radicals (˙O2−) and holes (h+) is reasonably proposed. [ABSTRACT FROM AUTHOR]

BiOCl has been identified to be a promising semiconductor material with exceptional performance for photodegradation of organic pollutants. In this work, a feasible strategy to synthesize octagon‐like BiOCl nanoflakes (G‐BiOCl NFs) with novel morphology was developed by one‐step solvothermal reaction in ethylene glycol/water solution with the addition of glutamate acid. The obtained G‐BiOCl NFs with large surface areas and negatively charged surfaces possessed excellent photocatalytic activity for the degradation of organic pollutant Rhodamine B (RhB). RhB was almost completely degraded in only 4 mins under ultraviolet−visible light irradiation. It was confirmed that the holes and.O2− played crucial roles in the RhB photocatalytic degradation process. This work provided a new strategy for the preparation of efficient photocatalysts. [ABSTRACT FROM AUTHOR]

In this communication, we report the first demonstration of an efficient photoelectrochemical aptasensor based on sputtering Au nanoparticle-modified nanoporous BiVO4 for the excellent sensitive and selective detection of thrombin with a low detection limit of 0.5 pM and a large linear range. [ABSTRACT FROM AUTHOR]

In this communication, we report for the first time the demonstration of a lithium ion intercalation strategy to significantly enhance the photoelectrochemical water splitting performance on 3-dimensional vertical hierarchical top-porous-bottom-tubular TiO2 nanotubes on a fabricable titanium mesh. [ABSTRACT FROM AUTHOR]

In this communication, a new photoelectrochemical aptasensor with Au nanoparticle functionalized self-doped TiO2 nanotube arrays (Au/SD-TiO2 NTs) as the core sensing unit and aptamers as the recognition unit was set up to accomplish the sensitive and selective detection of kanamycin with the lowest detection limit of 0.1 nM. [ABSTRACT FROM AUTHOR]

In this work, we proposed to utilize three-dimensional porous copper foam (CF) as conductive substrate and precursor of in-situ growth CuO nanowires (NWs) for fabricating electrochemical nonenzymatic glucose sensors. The CF supplied high surface area due to its unique three-dimensional porous foam structure, and thus resulted in high sensitivity for glucose detection. The CuO NWs/CF based nonenzymatic sensors presented reliable selectivity, good repeatability, reproducibility, and stability. In addition, the CuO NWs/CF based nonenzymatic sensors have been employed for practical applications, and the glucose concentration in human serum was measured to be 4.96 ± 0.06 mM, agreed well with the value measured from the commercial available glucose sensor in hospital, and the glucose concentration in saliva was also estimated to be 0.91 ± 0.04 mM, which indicated that the CuO NWs/CF owned the possibility for noninvasive glucose detection. The rational design of CuO NWs/CF provided an efficient strategy for fabricating of electrochemical nonenzymatic biosensors. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM) is an innovative procedure that can quickly create complex structures. By layering a material, a three-dimensional object is created using this technique. Every deposit of liquefied or partly liquefied material abides by the previous deposit. Fused deposition modelling's (FDM) objective is to comprehend how varied interior structures influence the bending resistance of the printed samples and to investigate the impact of various infill patterns and percentages. The term "infill" describes the pattern of solid material used to fill a 3D-printed object's interior. It is utilized to give the printed part structural support and strength. Acrylonitrile butadiene styrene (ABS) material was chosen for this study as it offers a greater and superior finished plane along with dimensional stability. The infill pattern chosen for the flexural test study was the triangular pattern which includes different densities of infill percentages precisely, 25%, 50%, 75%, and 100%. A few specimens of ABS material having 100% infill density are put through a tensile test according to the ASTM D638. The ASTM D790 standard was used to make a model and test the flexural strength of the specimen. Line and triangle patterns provided the most ideal tensile and bending strength properties. This is likely because the deposited rasters are associated with the direction of loading. For line patterns with 100% infill, scanning electron microscopy (SEM) analysis showed a convincing connection between the microstructures and the rasters (porosity, voids, gap between beads and hole due to polymer pulled out). Furthermore, SEM analysis showed matrix failure and significant voids in a triangular pattern at infill densities of 25%, 50%, 75%, and 100%. [ABSTRACT FROM AUTHOR]

One-dimensional nanocomposites of metal-oxide and noble metal were expected to present superior performance for nonenzymatic glucose detection due to its good conductivity and high catalytic activity inherited from noble metal and metal oxide respectively. As a proof of concept, we synthesized gold and copper oxide (Au/CuO) composite with unique one-dimensional nanocauliflowers structure. Due to the nature of the synthesis method, no any foreign binder was needed in keeping either Au or CuO in place. To the best of our knowledge, this is the first attempt in combining metal oxide and noble metal in a binder-free style for fabricating nonenzymatic glucose sensor. The Au/CuO nanocauliflowers with large electrochemical active surface and high electrolyte contact area would promise a wide linear range and high sensitive detection of glucose with good stability and reproducibility due to its good electrical conductivity of Au and high electrocatalytic activity of CuO. [ABSTRACT FROM AUTHOR]

Xu, Y.; Liao, B.; Jiang, Z.; Xin, K.; Xiong, Y., and Zhang, Y., 2021. Examining the differences between invasive Sonneratia apetala and native Kandelia obovata for mangrove restoration: Soil organic carbon, nitrogen, and phosphorus content and pools. Journal of Coastal Research, 37(4), 708–715. Coconut Creek (Florida), ISSN 0749-0208. Mangroves play an important role in enhancing soil organic carbon (SOC) and nutrient pools. The exotic Sonneratia apetala is widely used for the restoration of mangroves in China because of its fast growth. However, it is not clear whether S. apetala increases SOC, nitrogen, and phosphorus pools compared with the native mangrove species. Thus, the aims of this study were to determine whether Kandelia obovata and the fast-growing mangrove species S. apetala have advantages with regard to the SOC, nitrogen, and phosphorus content and pools and whether restored mangroves have SOC, nitrogen, and phosphorus content and pools similar to those of original mangroves. Four sites in the Qi'ao-Dangan Provincial Nature Reserve were selected: a 15-year-old planted S. apetala forest, a 15-year-old planted K. obovata forest, a native K. obovata forest, and an unvegetated mudflat. The content and pools of organic carbon, nitrogen, and phosphorus in the soil were compared. Compared with mudflats, the content and pools of SOC, nitrogen, and phosphorus were significantly increased by planting S. apetala. However, compared with the 15-year-old planted K. obovata, the fast-growing S. apetala showed no advantage. The content and pools of SOC and nitrogen in the 15-year-old planted S. apetala site were lower than those of native K. obovata forests. It is recommended that more native mangrove species be used for future mangrove restoration to increase the content and pools of SOC, nitrogen, and phosphorus. [ABSTRACT FROM AUTHOR]

Xu, Y.; Liao, B.; Jiang, Z.; Xin, K.; Xiong, Y., and Guan, W., 2021. Emission of greenhouse gases (CH4 and CO2) into the atmosphere from restored mangrove soil in South China. Journal of Coastal Research, 37(1), 52–58. Coconut Creek (Florida), ISSN 0749-0208. Mangroves are a special ecosystem in tropical and subtropical coastal areas. Currently, it is not adequately understood whether soils in restored mangroves are a substantial source of greenhouse gases. The objectives of this study were to determine whether restored mangrove soils are a substantial source of carbon dioxide (CO2) and methane (CH4) and to identify environmental factors affecting soil CO2 and CH4 fluxes in mangrove sites. From August 2019 to January 2020, CO2 and CH4 flux surveys were conducted in soils at four planted mangrove sites, dominated by Excoecaria agallocha, Kandelia obovata, Bruguiera gymnorrhiza, and Hymenocallis littoralis, respectively, in a mangrove reserve in southern China. The results showed that the CO2 and CH4 flux ranges of the four mangrove sites were 0.9432–1.7892 mmol m–2 h–1 and –0.104 to 0.845 µmol m–2 h–1, respectively. Soil CO2 flux was strongly positively (p < 0.01) correlated with soil organic carbon content and positively correlated (p < 0.05) with soil total N content, temperature, and redox potential. CH4 flux was positively correlated with soil temperature. The results confirm that these restored mangrove soils are only a small greenhouse gases source to the atmosphere. [ABSTRACT FROM AUTHOR]