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Spherical γ-In2Se3 and flower-like γ-In2Se3 are successfully prepared by simple hydrothermal method using absolute ethanol and deionized water as solvents, respectively. The microstructure, structure, chemical composition and optical properties of the prepared γ-In2Se3 are studied by XRD, SEM, EDS, XRD, Raman, UV–vis and PL spectroscopy. The UV–vis absorption spectra show that spherical γ-In2Se3 and flower-like γ-In2Se3 have significant light absorption in both visible and near-ultraviolet light regions, where the absorption threshold is about 900 nm. In this work, the dose of CTAB as an active agent and stabilizer plays an important role in the morphology of gamma phase indium selenide. Our results reveal a new approach for the synthesis of γ-In2Se3 with the better morphology and excellent optical properties.

Additional file 1: Fig. S1. Methyl-β-cyclodextrin efficiently clears accumulated cholesterol in the presence of U18666A and bafilomycin A1. A RPE1 cells were treated with or without different concentration of MβCD in a serum-starvation medium for 24 hours. Cells were then subjected to Western blot for LC3, SQSTM1, phospho-RPS6, RPS6, and ACTB. B Cells were either treated with U18666A (2 μg) or bafilomycin (25 nM) for 12 hours in a serum-starvation medium. Cell were further incubated for additional 24 hours or incubated for additional 24 hours with MβCD (10 μM or 20 μM) without changing the medium. Cells were then subjected to filipin staining. Scale bar, 20 μm. C, D Fluorescence intensities of filipin were measured by ImageJ Software. Filipin intensity from 50 cells were acquired for each experimental group. Bar graph represents mean ± SD (n = 3 experiments). *P < 0.05, Student's t-test. Fig. S2. Methyl-β-cyclodextrin enhances LAMP1 localization to GFP-LC3 positive structure in the presence of U18666A and bafilomycin A1. A RPE1 cells were treated with U18666A (2 μg), chloroquine (5 μM) or bafilomycin A1 (25 nM) for 12 hours in a serum-starvation medium. Cells further incubated with or without MβCD (20 μM) for additional 24 hours without changing medium. GFP-LC3 transfection transfection was carried out and after 6 hours of transfection cells were fixed by 4% paraformaldehyde and immunostained with LAMP1 antibody. Scale bar, 10 μm. B Quantification of GFP-LC3 puncta overlapping with LAPM1 was quantified from 30 transfected cells by using ImageJ software. Bar graph represents mean ± SD (n = 3 experiments). #P < 0.05, Student's t-test (test group were compared with control). *P < 0.05 Student's t-test (respective test groups were compared in the presence or absence of MβCD).

The cactus-like Cu2-xSe@Cu2-xSe nanowalls was prepared by secondary growth method using Cu2-xSe nanowalls as substrate. This special nanostructure comprises Cu2-xSe nano spines neatly growing on the sharp edges of Cu2-xSe nanowalls. Reaction time has a powerful effect on the formation and morphologies of Cu2-xSe nanowalls. XRD analysis indicated the cubic berzelianite phase of Cu2-xSe. The cactus-like Cu2-xSe@Cu2-xSe nanowalls presents a better field electron emission performance than the first synthesized Cu2-xSe nanowalls, possessing the turn-on field 2.04 V/μm and the enhancement factor of 5181. The formation mechanism of cactus-like Cu2-xSe@Cu2-xSe nanowalls was discussed and proposed. The results indicated that the cactus-like Cu2-xSe@Cu2-xSe nanowalls can be used as a promising material in field emission applications.

Different morphologies of CdSe and GO (graphene oxide)/CdSe microspheres like wool ball and walnut shape have been made through hydrothermal method using CTAB as surfactant. X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), X-ray energy dispersive spectrometer (EDS), scanning electron microscope (SEM), Raman spectra, and UV–vis absorption spectrum, were used to intensively investigate the structures, morphologies, chemical compositions and optical properties of CdSe and GO/CdSe microspheres. The results of XRD revealed that GO/CdSe microspheres have lead-zinc mineral structure. The results of XRD, EDS, XPS and Raman spectra showed that GO/CdSe microspheres were grown on GO sheets. Also UV–vis absorption spectrum indicated that GO/CdSe microspheres enhanced absorbance in UV light region and visible light region. Through comparative experiments, the results showed that pH = 4 is the optimal pH value for degrading Rhodamine B (RhB) solution. To study the photocatalytic performance of GO/CdSe microspheres, we catalyzed the degradation of RhB aqueous solution irradiated by visible light. The photocatalytic results showed that the wool ball-like GO/CdSe microspheres exhibited better photocatalytic activity than rough CdSe.

Exposure to arsenic in the environment is hazardous to biota. Three types of sediments from a shallow, high arsenic aquifer were collected from Jianghan Plain, Central China to investigate interactions between indigenous bacterial activity and arsenic adsorption/desorption. For the same level of bacterial activity, the As(III) or As(V) adsorption rate in sediments decreased from clay loam to loamy sand to silty sand. However, the arsenic desorption rate from these sediments followed the reverse sequence. For the same arsenic speciation and content, bacterial activity decreased from clay loam to loamy sand to silty sand. Overall, arsenic adsorption/desorption rates were related to both bacterial activity and sediment texture. The bacteria present could reduce As(V) to As(III), thereby favoring its release from sediment into solution and increasing the ratio of As(III) to total arsenic. These results indicate indigenous bacteria strongly affect the adsorption/desorption and oxidation-reduction of arsenic, and are actively involved in the dynamic equilibrium of arsenic between sediment and groundwater in this shallow aquifer.

A recyclable photoelectrode with high degradation capability for organic pollutants is crucial for environmental protection and, in this work, a novel CeO2 quantum dot (QDs)/Ag2Se Z-scheme photoelectrode boasting increased visible light absorption and fast separation and transfer of photo-induced carriers is prepared and demonstrated. A higher voltage increases the photocurrent and 95.8% of tetracycline (TC) is degraded by 10% CeO2 QDs/Ag2Se in 75 minutes. The degradation rate is superior to that achieved by photocatalysis (92.3% of TC in 90 min) or electrocatalysis (27.7% of TC in 90 min). Oxygen vacancies on the CeO2 QDs advance the separation and transfer of photogenerated carriers at the interfacial region. Free radical capture tests demonstrate that &bull, O2&minus, &bull, OH, and h+ are the principal active substances and, by also considering the bandgaps of CeO2 QDs and Ag2Se, the photocatalytic mechanism of CeO2 QDs/Ag2Se abides by the Z-scheme rather than the traditional heterojunction scheme. A small amount of metallic Ag formed in the photocatalysis process can form a high-speed charge transfer nano channel, which can greatly inhibit the photogenerated carrier recombination, improve the photocatalytic performance, and help form a steady Z-scheme photocatalysis system. This study would lay a foundation for the design of a Z-scheme solar photocatalytic system.

This paper introduces a novel triple-component silver phosphate-cobalt ferrite-graphene oxide (Ag 3 PO 4 -CoFe 2 O 4 -GO) photocatalyst, illustrates its synthetic principle of adjusting the pH value, elaborates on its dual-channel reaction mechanism and reveals its advantages. Morphology and elementary analyses revealed that the magnetic CoFe 2 O 4 nanoparticles (NPs) and the GO were uniformly adorned on the Ag 3 PO 4 particles’ surface, forming a spherical structure. Because of this particular structure, not only could the Ag 3 PO 4 -CoFe 2 O 4 -GO composite be thoroughly removed with magnet field from treated water, but the photocatalytic activity and stability had been greatly improved to pure Ag 3 PO 4 . The effects of different samples were also evaluated, in terms of the efficiencies in inactivation and degradation. The reactive oxygen species (ROSs) yield measurements and photoluminescence spectra analysis indicated that O 2 adsorption could be promoted by the CoFe 2 O 4 and the GO. Upon visible light irradiation, a part of motivated electrons of the Ag 3 PO 4 were consumed by the CoFe 2 O 4 , and others were transferred to the GO. The effective electron-hole separation is due to the dual transfer channel existing in the Ag 3 PO 4 -CoFe 2 O 4 -GO composite. Hence, the dual transfer channel is the major reason for enhancing photocatalytic activity and stability.

A number of arsenate-reducing bacteria respire adsorbed As(V), producing As(III) and thus contributing to arsenic mobilization from the solid phase to the aqueous phase. Two arsenate reducing genes, arsC and arrA, were both amplified in an indigenous bacterium Bacillus XZM isolated from high arsenic aquifer sediments. The effect of phosphate input on this novel bacterium in terms of mediating the biogeochemical behavior of arsenic was investigated for the first time. The results show bacterial growth and arsenate reduction appear to increase with the addition of phosphate. Input of 1 mM phosphate reduced the negative effects of As(V) on bacterial growth, resulting in 55–60% greater biomass production compared to lower phosphate inputs (0.01 and 0.1 mM). The data of real-time quantitative PCR (qPCR) indicated arsenate was involved in the expressions of two arsenate reductase genes (arsC and arrA genes) in indigenous bacterium Bacillus XZM. Overall, the addition of phosphate (from 0.1 to 1 mM) resulted in a doubling of arsenate bio-desorption from the sediment into the aqueous medium. Oxidation-reduction potential, as an environmental indicator of the bacterial reduction of metals, declined to −200 mV in the presence of strain XZM and 1 mM phosphate in the microcosm. Phosphate input enhanced arsenic biomigration, indicating the effect of phosphate concentration should be considered when studying the biogeochemical behavior of arsenic.

Crystals grown in the direction of high-energy facets have reduced surface energy, a small portion of high-energy crystal facets, and high photocatalytic activity. In this work, γ-In2Se3 nanoparticles with predominantly exposed {110} facets are synthesized hydrothermally in the presence of ethylenediaminetetraacetic acid (EDTA). EDTA plays a key role in regulating the exposed {110} facets and by adding 0.04 M of EDTA, tetragonal prismatic γ-In2Se3 nanoparticles with the {110} facets are produced. Studies of the photocatalytic activity of tetracycline (TC) reveal that the tetragonal prismatic γ-In2Se3 prepared with 0.04 M EDTA has the optimal activity that is about 1.9 times higher than that of conical γ-In2Se3 prepared without EDTA. The capture experiments show that h+ and O 2− affect degradation of TC and our results reveal a novel strategy to synthesize γ-In2Se3 with the optimal morphology and photocatalytic activity.