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1.
Nat Commun ; 11(1): 659, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005802

RESUMO

In atomically-thin two-dimensional (2D) semiconductors, the nonuniformity in current flow due to its edge states may alter and even dictate the charge transport properties of the entire device. However, the influence of the edge states on electrical transport in 2D materials has not been sufficiently explored to date. Here, we systematically quantify the edge state contribution to electrical transport in monolayer MoS2/WSe2 field-effect transistors, revealing that the charge transport at low temperature is dominated by the edge conduction with the nonlinear behavior. The metallic edge states are revealed by scanning probe microscopy, scanning Kelvin probe force microscopy and first-principle calculations. Further analyses demonstrate that the edge-state dominated nonlinear transport shows a universal power-law scaling relationship with both temperature and bias voltage, which can be well explained by the 1D Luttinger liquid theory. These findings demonstrate the Luttinger liquid behavior in 2D materials and offer important insights into designing 2D electronics.

2.
ACS Nano ; 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32052962

RESUMO

Nanoscale laser sources with downscaled device footprint, high energy efficiency and operation speed are pivotal for a wide array of opto-electronic and nanophotonic applications ranging from on-chip interconnects, nano-spectroscopy, sensing to optical communication. The capability of on-demand lasing output with reversible and continuous wavelength tunability over broad spectral range enables key functionalities in wavelength-division multiplexing (WDM) and finely controlled light-matter interaction, which remains an important subject under intense research. In this study, we demonstrate an electrically controlled wavelength-tunable laser based on CdS nanoribbon (NR) structure. Typical 'S'-shaped characteristics of pump power dependence was observed for dominant lasing lines, with concomitant line width narrowing. By applying an increased bias voltage across the NR device, the lasing resonance exhibits a continuous tuning from 510 nm to 520 nm for a bias field ranged within 0 kV/cm - 15.4 kV/cm. Systematic bias-dependent absorption and time-resolved photoluminescence (PL) measurements were performed, revealing a red-shifted band edge of gain medium and prolonged PL lifetime with increased electric field over the device. Both current-induced thermal reduction of band gap and Franz-Keldysh effect were identified to account for the modification of lasing profile, with the former factor playing the leading role. Furthermore, dynamical switching of NR lasing was successfully demonstrated, yielding a modulation ratio up to ~ 21 dB. The electrically tuned wavelength-reversible CdS NR laser in this work, therefore, presents an important step towards color-selective coherent emitters for future chip-based nano-photonic and opto-electronic circuitry.

3.
Small ; 16(5): e1905609, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31899596

RESUMO

All-inorganic halide perovskites (IHPs) have attracted enormous attention due to their intrinsically high optical absorption coefficient and superior ambient stabilities. However, the photosensitivity of IHP-based photodetectors is still restricted by their poor conductivities. Here, a facile design of hybrid phototransistors based on the CsPbBr3 thin film and indium tin oxide (ITO) nanowires (NWs) integrated into a InGaZnO channel in order to achieve both high photoresponsivity and fast response is reported. The metallic ITO NWs are employed as electron pumps and expressways to efficiently extract photocarriers from CsPbBr3 and inject electrons into InGaZnO. The obtained device exhibits the outstanding responsivity of 4.9 × 106 A W-1 , which is about 100-fold better than the previous best results of CsPbBr3 -based photodetectors, together with the fast response (0.45/0.55 s), long-term stability (200 h in ambient), and excellent mechanical flexibility. By operating the phototransistor in the depletion regime, an ultrahigh specific detectivity up to 7.6 × 1013 Jones is achieved. More importantly, the optimized spin-coating manufacturing process is highly beneficial for achieving uniform InGaZnO-ITO/perovskite hybrid films for high-performance flexible detector arrays. All these results can not only indicate the potential of these hybrid phototransistors but also provide a valuable insight into the design of hybrid material systems for high-performance photodetection.

4.
Phys Chem Chem Phys ; 22(3): 1591-1597, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31894783

RESUMO

In this work, hydrogen (H) plasma treatment is implemented to dope indium gallium zinc oxide (InGaZnO), zinc oxide (ZnO), and indium oxide (In2O3) thin-film transistors (TFTs). We systematically analyze the active defect states inside these n-type metal oxides and reveal how they are impacted by H dopant incorporation, combining the device transfer characteristics (including the threshold voltage, subthreshold slope, and carrier mobility), the X-ray photoelectron spectra, and numerical and theoretical investigations. An increase of the field-effect mobility of these TFTs is mainly attributed to the decreased interface and bulk tail-distributed traps, after an appropriate amount of H dopants is incorporated. In ZnO, hydrogen exclusively acts as a shallow donor during the plasma treatment, while the zinc vacancies Zn(Vac) cannot be passivated by the H dopants as no improvement of the subthreshold slope (SS) is observed in the hydrogenated ZnO TFT. The H interstitials (Hi) incorporated into In2O3 are stable in the + charge state at equilibrium, then change into the - charge state as the Fermi level energy EF gets closer to the bottom of the conduction band. Due to the H insertion into an oxygen vacancy VO, the VOH complex (acting as an acceptor) is formed in InGaZnO with increased H plasma treatment duration, leading to the degraded SS. This paper clarifies the H dopants' role and the different dominant defects inside the three types of TFTs, which may benefit systematic understanding and exploration of H dopant incorporation into InGaZnO, ZnO and In2O3 films for TFT improvement and optimization.

5.
Nanotechnology ; 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31935691

RESUMO

We report a heavily Yb3+/Al3+/B3+/F- co-doped high silica rod with a negative refractive index relative to pure silica. The high silica rod was fabricated from nanoporous silica rod by the glass phase-separation technology. For lowering the refractive index, B3+ and F- were simultaneously introduced into the silica rod. The optical properties of the silica rod were investigated. The fiber preform was prepared by the rod-in-tube method by which the Yb3+ doped high silica rod was only used as an active core. The fiber has a core diameter of 80 µm and a cladding diameter of 400 µm. The measurements show that the Yb3+ in the high silica fiber core is 15856 ppm by weight, while the refractive index is 0.0024 lower than that of the inner cladding. The amplification performance of the fiber was investigated. It is indicated that the nanoporous silica glass based on the glass phase-separation technology has a great potential for gain-guided index anti-guided high silica fiber.

6.
Adv Mater ; 32(6): e1907527, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31867813

RESUMO

Organic-inorganic hybrid perovskites (PVKs) have recently emerged as attractive materials for photodetectors. However, the poor stability and low electrical conductivity still restrict their practical utilization. Owing to the quantum-well feature of two-dimensional (2D) Ruddlesden-Popper PVKs (2D PVKs), a promising quasi-2D PVK/indium gallium zinc oxide (IGZO) heterostructure phototransistor can be designed. By using a simple ligand-exchange spin-coating method, quasi-2D PVK fabricated on flexible substrates exhibits a desirable type-II energy band alignment, which facilitates effective spatial separation of photoexcited carriers. The device exhibits excellent photoresponsivity values of >105 A W-1 at 457 nm, and broadband photoresponse (457-1064 nm). By operating the device in the depletion regime, the specific detectivity is found to be 5.1 × 1016 Jones, which is the record high value among all PVK-based photodetectors reported to date. Due to the resistive hopping barrier in the quasi-2D PVK, the device can also work as an optoelectronic memory for near-infrared information storage. More importantly, the easy manufacturing process is highly beneficial, enabling large-scale and uniform quasi-2D PVK/IGZO hybrid films for detector arrays with outstanding ambient and operation stabilities. All these findings demonstrate the device architecture here provides a rational avenue to the design of next-generation flexible photodetectors with unprecedented sensitivity.

7.
Sci Total Environ ; : 135157, 2019 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-31836235

RESUMO

Dissolved oxygen (DO) undountedly affects fish distribution, metabolism, and evern survival. Intensive aquaculture and environmental changes will inevitably lead to hypoxic stress for largemouth bass (Micropterus salmoides). The different metabolic responses and mechanism still remains relatively unknown during acute hypoxia exposure. In this study, largemouth bass were subjected to hypoxic stress (3.0 ± 0.2 mg/L and 1.2 ± 0.2 mg/L) for 24 h and 12 h reoxygenation to systemically evaluate indicators of glucose and lipid metabolism. A regulatory network was constructed using RNA-seq to further elucidate the transcriptional regulation of glucose and lipid metabolism. During hypoxia for 4 h, the liver glycogen, glucose and pyruvic acid contents significantly decreased, whereas plasma glucose content and liver lactic acid content increased significantly. The accumulation of liver triglycerides and non-esterified fatty acids was enhanced during hypoxia for 8 h. The activity of key enzymes revealed the different metabolic responses to hypoxia exposure for 4 h, including the enhancement of glycolysis, and inhibition of gluconeogenesis. Furthermore, hypoxia exposure for 8 h increased lipid mobilization, and inhibited the ß-oxidation. In addition, an integrated regulatory network of 9 major pathways involved in the response to hypoxia exposure was constructed, including HIF signaling pathway, VEGF signaling pathway, AMPK signaling pathway, insulin signaling pathway and PPAR signaling pathway; glycolysis/gluconeogenesis, pyruvate metabolism, fatty acid degradation and fatty acid biosynthesis. Additionally, reoxygenation inhibited glycolysis, and promoted gluconeogenesis and lipid oxidation, but energy deficits persisted. In short, although the mobilization and activation of fatty acid in liver were enhanced in the early stage of hypoxia, glycolysis was the main energy source under acute hypoxia. The extent and duration of hypoxia determine the degree of change in energy metabolism.

8.
Opt Express ; 27(23): 33135-33142, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31878387

RESUMO

With the research of hollow-core fiber with large core diameter, the coupling efficiency from hollow-core fiber with large core diameter to single-mode fiber is difficult to increase through the traditional technology, we proposed a novel coupling method to improve the coupling efficiency by attaching a pure silica small ball at the front end of single-mode fiber, the coupling efficiency of 50% from hollow-core fiber with a large core diameter of 110 µm to single-mode fiber can be achieved.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31770642

RESUMO

High temperatures and low oxygen in aquatic environments, such as intensive aquaculture or in natural watersheds, inevitably cause stress in fish. Fish are exposed to high temperatures during the summer, which exacerbates hypoxia. Hypoxia (1.2 ± 0.2 mg/L) under 20 °C (20 HG) and 26 °C (26 HG) was simulated to induce stress in largemouth bass (Micropterus salmoides). Related enzymes and genes involved in antioxidant, immune, and apoptotic responses were selected to explore the interactive effects of temperature and hypoxia on largemouth bass. The results showed that malondialdehyde (MDA) levels in plasma, gill, and liver increased in the 26 HG (p < 0.05). Liver superoxide dismutase (SOD) activity increased in the 26 HG. Peak SOD (SOD1, SOD2, SOD3a, and SOD3b), CAT, and GSH-Px mRNA levels in the gill and liver were observed at 12-24 h of stress. The levels of gill and liver total antioxidant capacity, catalase (CAT), glutathione peroxidase (GSH-Px) activities and other enzyme activities and genes in the 26 HG were higher than those in the 20 HG (p < 0.05). The gill and liver acid phosphatase and alkaline phosphatase activities increased with time in the 26 HG (p < 0.05), while gill and liver lysozyme activities in the 26 HG were lower than those in the 20 HG (p < 0.05). Tumor necrosis factor-α mRNA level was upregulated in the gill and downregulated in the liver at 24 h in the 26 HG. Interleukin (IL)-1ß and IL-8 mRNA levels were upregulated in the gill and liver in the 26 HG at 24 h, whereas IL-15 mRNA level was downregulated in the 26 HG at 12 h. Transforming growth factor-ß1 mRNA level was upregulated in the gill in the 20 HG at 24 h, but downregulated in gill and liver in the 26 HG at 24 h. Similarly, IL-10, Hepcidin-1, and Hepcidin-2 showed lower expression levels in the 26 HG. Gill and liver caspase-3 activities were higher in the 26 HG (p < 0.05), and gill caspase-3 activity was higher than that in the liver. The mRNA levels of proapoptotic genes (caspase-3, caspase-8, and caspase-9) were higher in the 26 HG. The present study demonstrates the interactive effects of temperature and hypoxia on stress in largemouth bass gill and liver. These results will be helpful to understand the mechanisms of stress induced by temperature and hypoxia in fish and provide a theoretical basis for aquaculture management.

10.
Nat Commun ; 10(1): 5013, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31676774

RESUMO

For atomically thin two-dimensional materials, interfacial effects may dominate the entire response of devices, because most of the atoms are in the interface/surface. Graphene/sapphire has great application in electronic devices and semiconductor thin-film growth, but the nature of this interface is largely unknown. Here we find that the sapphire surface has a strong interaction with some of the carbon atoms in graphene to form a C-O-Al configuration, indicating that the interface interaction is no longer a simple van der Waals interaction. In addition, the structural relaxation of sapphire near the interface is significantly suppressed and very different from that of a bare sapphire surface. Such an interfacial C-O-Al bond is formed during graphene growth at high temperature. Our study provides valuable insights into understanding the electronic structures of graphene on sapphire and remote control of epitaxy growth of thin films by using a graphene-sapphire substrate.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31677400

RESUMO

Water temperature can affect the metabolism of fish. Common carp (Cyprinus carpio) is a representative eurythermic fish that can survive at a wide range of ambient temperatures, allowing it to live in an extensive geographical range. The goal of this work was to study the glucose metabolism of common carp at different temperatures and determine the miRNAs involved in the regulation of glucose metabolism. We determined the indicators related to glucose metabolism after long-term temperature stress and constructed nine small RNA libraries of livers under different temperature stress (5 °C, 17 °C, and 30 °C, with three biological replicates for each temperature), and subjected these samples to high-throughput sequencing. A positive relationship was observed between weight gain rate (WGR) and temperature increase after 18 days of temperature stress. However, the glucose level in the plasma maintained a gentle decrease. Unexpectedly, liver lactic acid levels were elevated in HTG (high temperature group) and LTG (low temperature group). Six down-regulated miRNAs (miR-122, miR-30b, miR-15b-5p, miR-20a-5p, miR-1, and miR-7b) were identified as involved in the regulation of glycolysis. Twelve genes were predicted as targets of these miRNAs, and these genes are in pathways related to pyruvate metabolism, glycolysis/gluconeogenesis, and the citrate cycle (TCA cycle). The results allowed prediction of a potential regulatory network of miRNAs involved in the regulation of glycolysis. The target genes of six down-regulated miRNAs were up-regulated under temperature stress, including Aldolase C, fructose-bisphosphate, b (ALDOCB), multiple inositol-polyphosphate phosphatase 1 (MINPP1), phosphoenolpyruvate carboxykinase 1 (PCK1), pyruvate dehydrogenase E1 alpha 1 (PDHA1), aldehyde dehydrogenase 9 family member A1a (ALDH9A1A), Acetyl-coenzyme A synthetase (ACSS), lactate dehydrogenase b (LDH-b), and glyoxylate reductase/hydroxypyruvate reductase (GRHPR). Other key genes of glycolysis, glucose transporter 1 (GLUT-1), pyruvate kinase PKM (PKM), and mitochondrial pyruvate carrier (MPC) were significantly up-regulated in LTG and HTG. Overall, the results suggest that miRNAs maintain their energy requirements by regulating glycolysis and play an important role in the molecular response to cold and heat stress of common carp. These data provide the foundation for further studies of the role of miRNAs in environmental adaptation in fish.

12.
Opt Express ; 27(15): 20824-20836, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31510171

RESUMO

A gain-tailored Ge-free Yb/Ce codoped aluminosilicate fiber is fabricated by MCVD combined with solution doping technique. Through regulating the temperature in the tube and designing the solution doping process, the refractive index profile of this fiber is close to a step-index without any center dip. The laser performance of this fiber is proved through contrast experiments with conventional fiber in a kW-level MOPA setup. The gain-tailored fiber amplifier presents a beam quality of M2 ~1.43 at 1.2 kW. Its MI threshold is 1.25 kW, about 1.74 times as much as that of the conventional fiber amplifier. The laser slope efficiency of the gain-tailored fiber amplifier is 86.75%. Stabilized at an output power of 1.1 kW for 15 hours, the MI threshold does not decrease after this long-term operation, demonstrating a strong resistance to photodarkening effect. These results have confirmed that MCVD-fabricated gain-tailored Yb/Ce codoped aluminosilicate fibers have great potential in power scaling and output stability of high-power fiber lasers and amplifiers.

13.
Opt Express ; 27(18): 25964-25973, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31510458

RESUMO

Ytterbium-doped fiber (YDF) loaded with deuterium is used herein to mitigate mode instability. Experimental results reveal that this method can increase the mode instability threshold in a laser oscillator. Specifically, when the YDF was loaded with deuterium over two- and four-week periods, the mode instability threshold power increased from ∼459 W to ∼533 W (16%) and to ∼622 W (35%), respectively, but the respective laser efficiencies were almost unaffected (71.5% vs. 72.9% and 75.4%). In conclusion, deuterium loading is effective in the mitigation of mode instability. It is envisaged to be applied in the power scaling of high-power fiber lasers.

14.
ACS Appl Mater Interfaces ; 11(36): 33188-33193, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31415147

RESUMO

Metal-semiconductor-metal (MSM)-structured GaAs-based nanowire photodetectors have been widely reported because they are promising as an alternative for high-performance devices. Owing to the Schottky built-in electric fields in the MSM structure photodetectors, enhancements in photoresponsivity can be realized. Thus, strengthening the built-in electric field is an efficacious way to make the detection capability better. In this study, we fabricate a single GaAs nanowire MSM photodetector with superior performance by doping-adjusting the Fermi level to strengthen the built-in electric field. An outstanding responsivity of 1175 A/W is obtained. This is two orders of magnitude better than the responsivity of the undoped sample. Scanning photocurrent mappings and simulations are performed to confirm that the enhancement in responsivity is because of the increase in the hole Schottky built-in electric field, which can separate and collect the photogenerated carriers more effectively. The eloquent evidence clearly proves that doping-adjusting the Fermi level has great potential applications in high-performance GaAs nanowire photodetectors and other functional photodetectors.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31463754

RESUMO

Identification of different pollution sources in groundwater is challenging, especially in areas with diverse land uses and receiving multiple inputs. In this study, principal component analysis (PCA) was combined with geographic information system (GIS) to explore the spatial and temporal variation of groundwater quality and to identify the sources of pollution and main factors governing the quality of groundwater in a multiple land-use area in southwestern China. Groundwater samples collected from 26 wells in 2012 and 38 wells in 2018 were analyzed for 13 water quality parameters. The PCA results showed that the hydro-geochemical process was the predominant factor determining groundwater quality, followed by agricultural activities, domestic sewage discharges, and industrial sewage discharges. Agriculture expansion from 2012 to 2018 resulted in increased apportionment of agricultural pollution. In contrast, economic restructure and infrastructure improvement reduced the contributions of domestic sewage and industrial pollution. Anthropogenic activities were found the major causes of elevated nitrogen concentrations (NO3-, NO2-, NH4+) in groundwater, highlighting the necessity of controlling N sources through effective fertilizer managements in agricultural areas and reducing sewage discharges in urban areas. The applications of GIS and PCA successfully identified the sources of pollutants and major factors driving the variations of groundwater quality in tested years.

16.
ACS Nano ; 13(8): 9325-9331, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31322851

RESUMO

Two-dimensional transition metal dichalcogenides possess the K (K') valley degree of freedom (DOF). Based on that, the research on valleytronics draws considerable attention. In this report, by breaking the spatial-inversion symmetry by an out-of-plane electric field, the valley Hall effect (VHE) is observed in multilayer tungsten diselenide (WSe2) at room temperature. The non-zero Berry curvature emerges, leading to the carriers at K (K') valley being deflected to the opposite sides of the channel, giving rise to a spatial polarization of carriers at K (K') valleys in multilayer WSe2. This observation of the VHE illustrates that the K (K') valley DOF can be generated in multilayer WSe2, which makes it an alternative candidate for valleytronics.

17.
ACS Appl Mater Interfaces ; 11(28): 25516-25523, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31264836

RESUMO

In this report, a screening-engineered carbon nanotube (CNT) network/MoS2/metal heterojunction vertical field effect transistor (CNT-VFET) is fabricated for an efficient gate modulation independent of the drain voltage. The gate field in the CNT-VFET transports through the empty space of the CNT network without any screening layer and directly modulates the MoS2 semiconductor energy band, while the gate field from the Si back gate is mostly screened by the graphene layer. Consequently, the on/off ratio of CNT-VFET maintained 103 in overall drain voltages, which is 10 times and 1000 times higher than that of the graphene (Gr) VFET at Vsd = 0.1 (ratio = 81.9) and 1 V (ratio = 3), respectively. An energy band diagram simulation shows that the Schottky barrier modulation of CNT/MoS2 contact along the sweeping gate bias is independent of the drain voltage. On the other hand, the gate modulation of Gr/MoS2 is considerably reduced with increased drain voltage because more electrons are drawn into the graphene electrode and screens the gate field by applying a higher drain voltage to the graphene/MoS2/metal capacitor.

18.
Nanoscale ; 11(21): 10420-10428, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31112194

RESUMO

With continuous device scaling, avalanche breakdown in two-dimensional (2D) transistors severely degrades device output characteristics and overall reliability. It is highly desirable to understand the origin of such electrical breakdown for exploring high-performance 2D transistors. Here, we report an anomalous increase in the drain currents of black phosphorus (BP)-based transistors operating in the saturation regime. Through the comprehensive investigation of various channel thicknesses, channel lengths and operating temperatures, such novel behavior is attributed to the kink effect originating from impact ionization and the related potential shift inside the channel, which is further confirmed by device numerical simulations. Furthermore, nitrogen plasma treatment is carried out to eliminate the current anomalous increase and suppress the kink effect with improved saturation current. This work not only sheds light on the understanding of carrier transport within BP transistors, but also could open up a new avenue for achieving high-performance and reliable electronic devices based on 2D materials.

19.
ACS Nano ; 13(4): 4804-4813, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-30938515

RESUMO

As compared with epitaxial semiconductor devices, two-dimensional (2D) heterostructures offer alternative facile platforms for many optoelectronic devices. Among them, photovoltaic based photodetectors can give fast response, while the photogate devices can lead to high responsivity. Here, we report a 2D photogate photodiode, which combines the benefits of 2D black phosphorus/MoS2 photodiodes with the emerging potential of perovskite, to achieve both fast response and high responsivity. This device architecture is constructed based on the fast photovoltaic operation together with the high-gain photogating effect. Under reverse bias condition, the device exhibits high responsivity (11 A/W), impressive detectivity (1.3 × 1012 Jones), fast response (150/240 µs), and low dark current (3 × 10-11 A). All these results are already much better in nearly all aspects of performance than the previously reported 2D photodiodes operating in reverse bias, achieving the optimal balance between all figure-of-merits. Importantly, with a zero bias, the device can also yield high detectivity (3 × 1011 Jones), ultrahigh light on/off ratio (3 × 107), and extremely high external quantum efficiency (80%). This device architecture thus has a promise for high-efficiency photodetection and photovoltaic energy conversion.

20.
Sci Total Environ ; 671: 377-387, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-30933794

RESUMO

The magnetic poly(N-isopropylacrylamide)/chitosan hydrogel with interpenetrating network (IPN) structure was designed based on the functional groups of targeted emerging contaminants, represented by hydrophilic sulfamethoxazole (SMZ) and hydrophobic bisphenol A (BPA). The average particle size, specific surface area, and total pore volume of the hydrogel were turned out to be 103.7 µm, 60.70 m2/g and 0.0672 cm3/g, respectively. Adsorption results indicated that the maximum adsorption capacity occurred at the pH where SMZ was anionic and BPA was uncharged. When the adsorption temperature increased from 25 °C to 35 °C, the amount of adsorbed SMZ hardly changed, but that of BPA increased by two times. The adsorption capacity of the binary system (i.e., with both SMZ and BPA) was almost the same as that of the single system, indicating that simultaneous adsorption of SMZ and BPA was achieved. The adsorption equilibrium was reached quickly (within 5 min) for both SMZ and BPA. For adsorption isotherm, the Freundlich model fitted well for SMZ at 25, 35 and 45 °C. However, the adsorption of BPA exhibited the sigmoidally shaped isotherm at 25 °C with the Slips model fitting well, and both the Freundlich isotherm and the Slips isotherm fitted the data well at 35 °C and 45 °C, suggesting that the adsorption force was initially weak but greatly enhanced with an increase in adsorbate concentration or ambient temperature. The main adsorption mechanism was inferred to be electrostatic interactions for SMZ, and hydrophobic interactions as well as hydrogen bonding for BPA. The hydrogel adsorbent maintained favorable adsorption capacity for BPA after five adsorption-desorption cycles. These findings may provide a strategy for designing high performance adsorbents that can remove both hydrophilic and hydrophobic organic contaminants in the aquatic environment.

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