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Efficient electron transmission is an important step in the process of CO2 photoreduction. In this paper, a multi-interface-contacted In2S3/Au/reduced graphene oxide (rGO) photocatalyst with the fluorescence resonance energy transfer (FRET) mechanism has been successfully prepared by the solvothermal, self-assembly, and hydrothermal reduction processes. Photocatalytic CO2 reduction experiments showed that the In2S3/Au/rGO (IAr-3) composite exhibited excellent photoreduction performance and photocatalytic stability. The yields of CO and CH4 obtained after the photoreduction process with IAr-3 as the catalyst were around 4 and 6 times higher than those of pure In2S3, respectively. Photoelectrochemical analysis showed that the multi-interface contact and FRET mechanism greatly improved the generation, transmission, and separation efficiency of carriers photogenerated within the photocatalyst. In situ FTIR test was applied to analyze the photocatalytic CO2 reduction process. 13C isotope tracer test confirmed that the carbon source of CO and CH4 was the CO2 molecules in the photoreduction process rather than the decomposition of catalyst or TEOA. A potential enhanced photocatalytic mechanism has been discussed in total.

Nanoparticles can be prepared by several sophisticated processes but until now, it cannot be prepared by simple home cooking. Here, we report that two incidental food nanoparticles (iFNPs) consisting of proteoglycans and phytosterols were isolated from soup made from freshwater clam (Corbicula fluminea Muller), a renowned folk remedy for liver problems in China and other parts of East Asia. These two bioactive iFNPs were obtained and characterized by anionic exchange chromatography coupled with multi-angle laser light scattering measurement. Their hydrodynamic diameters and ζ-potentials were 50 ± 0.2 nm and -28.0 mV and 67 ± 0.4 nm and -9.96 mV, respectively. FT-IR revealed that the proteoglycans in the particles contained α-type heteropolysaccharides. Both iFNPs were resistant to pH changes and separation by mechanical force but responsive to temperature changes. They effectively inhibited cholesterol uptake in vitro, which resonates with the traditional belief that freshwater clam soup provides hepatoprotective benefits. This study suggests that these two proteoglycan-lipid iFNPs are the active moieties and offers a supramolecular structure-based approach to study the function of such complex matrices derived from food.

Z-scheme g-C3N4/Ag3VO4/reduced graphene oxide (rGO) photocatalysts with multi-interfacial electron-transfer paths enhancing CO2 photoreduction under UV-vis light irradiation were successfully prepared by a hydrothermal process. Transmission electron microscope images displayed that the prepared photocatalysts have a unique 2D-0D-2D ternary sandwich structure. Photoelectrochemical characterizations including TPR, electrochemical impedance spectroscopy, photoluminescence, and linear sweep voltammetry explained that the multi-interfacial structure effectively improved the separation and transmission capabilities of photogenerated carriers. Electron spin resonance spectroscopy and band position analysis proved that the electron-transfer mode of g-C3N4/Ag3VO4 meets the Z-scheme mechanism. The introduction of rGO provided more electron-transfer paths for the photocatalysts and enhanced the stability of Ag-based semiconductors. In addition, the π-π conjugation effect between g-C3N4 and rGO further improved the generation and separation efficiency of photogenerated electron-hole pairs. Then, the multiple channels (Ag3VO4 → CN, Ag3VO4 → rGO → CN, and rGO → CN) due to the 2D-0D-2D structure greatly improving the photocatalytic CO2 reduction ability have been discussed in detail.

Achieving the intelligent controllability of the photocatalyst to the surrounding environment is a very meaningful work. Here, the polyacrylic acid (PAA) modified Ag/AgCl-40/CN composite was constructed to achieve an intelligent response of pH value. PAA exhibits hydrophilic properties at high pH value, increasing the adsorption capacity to tetracycline (TC) molecules. The morphology of PAA from contracted state to diastolic state, releasing the Ag/AgCl-40/CN catalyst. In addition, PAA modified Ag/AgCl-40/CN can prevent the loss of AgCl. The g-C3N4 nanosheets (CN) as a carrier enhance the dispersibility of the AgCl particles. The LSPR effects of Ag nanoparticles produce more electrons acting on photocatalytic degradation. On the results of experiment, the degradation of TC by PAA@Ag/AgCl-40/CN shows an excellent degradation activity when the high pH value. Photoluminescence spectroscopy and photocurrent demonstrate that carrier separation efficiency of PAA@Ag/AgCl-40/CN is higher than CN and Ag/AgCl-40/CN. The detection of the main active substances •O2− and h+, revealing a reasonable mechanism for the PAA@Ag/AgCl-40/CN hybrid system. This work provides a procedure to obtain smart materials that can switch photocatalytic processes.

g-C3N4 quantum dots (CN QDs)-decorated mesoporous CeO2 composite photocatalyst was prepared by hydrothermal method. The characterized results exhibit that the CN QDs are successfully coupled with mesoporous CeO2, and the photoelectronic response is effectively enhanced. The photocatalytic activity was tested by CO2 reduction, and the results showed that when the loading of CN QDs was 0.75 wt%, the composite photocatalyst has the best photocatalytic activity. After 10 h of UV irradiation, the yields of CO and CH4 were 22.48 µmol/g and 15.81 µmol/g, respectively. Some of the electrons generated within m-CeO2 participated in the CO2 reduction reaction and some were transferred to CN QDs through the two-phase interface to participate in the CO2 catalytic reaction. The oxygen vacancies in m-CeO2 can adsorb CO2 and the introduced CN QDs can excite more oxygen vacancies with m-CeO2 heterostructure, thereby adsorbing more CO2 and photoreduction electrons.

It is extremely important for photocatalysts to exhibit intelligent responsiveness to their environment. Herein, a poly N-isopropyl acrylamide (PNIPAM)-modified Ag/Ag3PO4-20/CN hybrid material with excellent convertible photocatalytic activity is prepared. PNIPAM has good hydrophilicity below the lower critical solution temperature (LCST); this increases the capacity of the photocatalyst for adsorbing tetracycline (TC) molecules. In addition, the PNIPAM-modified Ag/Ag3PO4-20/CN can prevent the loss of Ag3PO4. The dispersity is improved by loading g-C3N4 nanosheets (CN) for enhancing the efficiency of photocatalytic activity. Furthermore, a Z-scheme heterostructure is formed between CN and Ag3PO4, accelerating the separation efficiency of the holes and electrons. Ag nanoparticles can be used as electron-shuttle mediators, and electrons receiving more energy are transferred via the localized surface plasmon resonance (LSPR) effect. Furthermore, the PNIPAM@Ag/Ag3PO4-20/CN photocatalyst exhibits an excellent degradation rate for the degradation of TC when the temperature is lower than the LCST. The photoluminescence spectra and photocurrent curves prove that the carrier-separation efficiency of PNIPAM@Ag/Ag3PO4-20/CN is higher than those of Ag/Ag3PO4/CN and CN. The main active species of ·O2− and h+ are detected to reveal the plausible mechanism of the PNIPAM@Ag/Ag3PO4-20/CN hybrid material system. This work provides a way to develop intelligent materials for switchable photocatalytic applications.

CdIn2S4 micro-flower spheres modified with Au NPs and rGO have been designed for CO2 photoreduction. The photoproduction yields of CO and CH4 were 4 and 5 times higher than that of pure CdIn2S4, respectively. The photoproduction of CO and CH4 from the photocatalytic CO2 reduction process has been evidenced by 13C isotope tracer tests. Au NPs act as both the acceptor of photogenerated electrons and the donor of hot electrons at the CdIn2S4 and rGO interface. Three electron transfer channels: CdIn2S4 → Au → rGO, CdIn2S4 → Au, and Au → rGO, efficiently improve the transfer efficiency of electrons. Meanwhile, CO2 adsorption is largely improved, as confirmed by DFT calculations which indicate that the CO2 adsorption ability of the C sites from rGO has been enhanced by Au NPs. In situ FTIR has been carried out to research the CO2 photoreduction process. This work demonstrates the importance of efficient electron transfer and excellent CO2 adsorption in improving the efficiency of CO2 photoreduction, providing an inspiring concept for future advancement in this area.

Si–Ge alloys are a new type of semiconductor material that are of great significance for the development of microelectronic technology, especially in the photoelectricity industry and for thermoelectric conversion in high temperature applications (>700 K). In the present work, a novel Ge allotrope in the C2/c phase with band gap of 1.102 eV was firstly proposed, which is suitable for the absorption of sunlight. C2/c-Ge are mechanically, dynamically and thermodynamically stable. A series of Si24-xGex alloys (x = 0, 8, 16, 24) in the C2/c phase with band gaps of 1.10–1.50 eV are predicted by ab initio calculations at ambient conditions. The Si24-xGex alloys (x = 0, 8, 16, 24) in C2/c phase have better absorption ability than that of the Si in diamond, hP12 and oC12 phases. The Si24-xGex alloys in the C2/c phase have the strong absorption in the visible, which have a great impact on the new-generation photovoltaic applications.

Photocatalytic reduction of CO2 by semiconductors is of great significance in generating value-added fuels. Here, we construct a novel S–C–S heterojunction constituted of MoS2/SnS2/r-GO by a simple...

Ag dots/flower-like MoS2/rGO multidimensional photocatalysts were successfully prepared via one-pot hydrothermal method. The characterizations of morphology and structure showed that the as-prepared photocatalysts with zero dimensional Ag dots, three dimensional flower-like MoS2 and two dimensional rGO composite structures have been clearly formed in composite multidimensional photocatalysts. Moreover, the photoelectronic performances exhibited that the composite multidimensional structure could efficiently enhance the transfer rate of charges. Especially the intensity of photocurrent was obviously improved after the Ag dots modified MoS2/rGO. The Ag/MoS2/rGO showed excellent photocatalytic activity of degradation tetracycline (TC), the removed rate of TC could reach 85.5% in 90 min. The species trapping experiments and electron spin resonance spin-trap tests clearly revealed that the h+ and ·O2− active species play the key roles during the photocatalytic degradation processes of TC. Overall, the composite multidimensional photocatalysts with zero, three and two dimensional in this work show a promising way to remove the TC wastewater, which suggested one strategy fabricate high active photocatalyst, and the photocatalytic mechanism was also discussed.

Photocatalytic technology provides a new strategy for the treatment of water pollution and energy crisis. Developing photocatalytic materials with high efficiency and stable visible light response has always been the direction of scientific researchers in the photocatalytic field. In this paper, we designed and prepared an efficient and stable rGO-modifited type-I Ag2S/g-C3N4 heterojunction photocatalyst (rGO/Ag2S/CN). The TEM (Transmission electron microscope) technology shows that the morphology of rGO/Ag2S/CN is a sandwich-like structure. UV–Vis DRS (UV–visible diffuse-reflectance spectrum) shows that the loading of Ag2S NPs and the modification of rGO effectively enhance the light response performance of nanocomposite materials in visible light. PL (Photoluminescence) and PEC (Photoelectrochemical) results prove that the photogenerated carriers transport and separation efficiency of rGO/Ag2S/CN have been improved. The photodegradation of RhB and the photoreduction of CO2 results confirmed that this ternary nanocomposite has great photocatalytic activity. The photodegradation efficiency of the RhB aqueous solution is about 98.5% after 30 min under the visible light irradiation. The photoreduction experiments showed that the yields of CO and CH4 are 178.05 μmol/g and 121.11 μmol/g, respectively after 8 h under the UV light irradiation. The results of cyclic photocatalytic experiments and the XRD pattern after those processes further revealed that the modification of rGO not only enhanced the photocatalytic performance of the nanocomposite photocatalyst, but also effectively improved the stability of Ag2S in the photocatalytic process. The possible photocatalytic reaction mechanisms were discussed in detail.

The Ce doping TiO2/halloysite nanotubes photocatalyst (Ce-TiO2/HNTs) was prepared for enhanced photocatalytic degradation of tetracycline (TC). The crystal structure, morphology and photoelectrochemical (PEC) properties have been researched by XRD, TEM, UV–vis DRS and other characterized technologies. The TEM results showed that the Ce-TiO2 nanoparticles were evenly dispersed on the surface of HNTs with about 5 nm pore structure. The UV–vis DRS results showed that the doping of Ce effectively broadened the photo-absorption capacity of the pure TiO2. The PEC results confirmed that the doping of Ce decreased the electrochemical impedance of the photogenerated carrier in the transfer process and greatly improved the photogenerated efficiency of the electron within the TiO2 NPs. The XPS analysis showed that Ce co-existed in the form of Ce3+ and Ce4+ oxidation states in the Ce-TiO2/HNTs. The photodegradation experiments showed that Ce-TiO2/HNTs exhibited the enhanced photocatalytic activity under the visible-light irradiation compared with the pure TiO2 NPs.

High selectivity and fast charge separation are two important factors for photocatalytic wastewater treatment. Herein, we prepared a molecular imprinted Ag/Ag3VO4/g-C3N4 photocatalyst (MIP) that exhibited great specific recognition ability along with excellent photocatalytic activity. The ultrathin g-C3N4 nanosheets with high surface are used to prepare. The Z-scheme Ag3VO4/g-C3N4 heterostructure and the surface plasmon resonance of the photoreduced Ag0 together contributed to the improvement of the separation efficiency of photogenerated electrons and holes. In addition, MIP provides the specific recognition ability to preferentially adsorb the target pollutant. The selectivity of photocatalysis was evaluated by the degradation of oxytetracycline and tetracycline solutions. Photoluminescence and transient photocurrent measurements further prove the improved charge separation efficiency of MIP. A plausible photocatalytic reaction mechanism is proposed based on electron spin resonance measurement and the active species trapping experiments, where indicates that the main active species of this photocatalytic process are O2- and h+. This research provides an effective strategy for the simultaneous enhancement of selectivity and activity via molecular imprinting.

A series of novel porous indium (III) oxide (In2O3) and nanocubic cerium oxide (CeO2) loading HCl treated attapulgite (HATP) ternary photocatalysts were successfully synthesized. Simultaneously, all photocatalysts were performed the CO2 reduction under UV-light. To explore the crystal structures, morphologies and electrochemical characteristics of as-synthesized samples, the XRD, SEM and TEM, and transient photocurrent techniques were performed in this work. Besides, as an optimized In2O3/CeO2/HATP sample presents the highest activity for CO (32.03 µmol/g) and CH4 (16.94 µmol/g) yields, which is 6.11-fold and 6.78-fold times higher than those of pure CeO2 under UV-light (8 W) irradiation.

The muti-dimensional carbon quantum dots (CQDs) modifying sphere-flower CdIn2S4 on nitrogen doping on reduced graphene oxide (N-rGO) photocatalyst is fabricated through the simple hydrothermal method and solvothermal method. CQDs/CdIn2S4/N-rGO composites show good photocatalytic degradation for 80% 50 mg/L 2,4-dichlorophenol under visible light for 6 h, which could be ascribable to the good conductive property and defects of N-rGO sheet (two dimension) and the heterojunction constructed between CQDs (zero dimension) and sphere-flower CdIn2S4 (three dimension), and synergism among them. These are evidenced by the photoluminescence spectra, photocurrent intensity, high-resolution transmission electron microscopy and Raman spectra. Besides, the results of ESR show that ·O2− and ·OH radicals both are generated under visible light, ·OH the main one further confirmed by free radicals trapping experiments. This work will give some inspirations for constructing multi-dimensional semiconductors with excellent photocatalytic performance.

A series of Au/g-C3N4 (Au/CN) nanocomposites were successfully prepared, where g-C3N4 nanosheets (CN NSs) served as a substrate for the growth of different sized Au nanoparticles (Au NPs) using the constant temperature bath-reduction method. The effect of Au NP size on electron transfer efficiency between the interfaces of the nanocomposite was studied. The three-dimensional finite-difference time-domain results revealed that larger Au NPs showed increased strength of the localized surface plasmon resonance effect. An increased number of high-energy electrons were available for transfer from Au NPs to CN under the visible light irradiation, inhibiting electron transfer from CN to Au NPs. Photoelectrochemical performance analysis showed that smaller Au NPs exhibited higher separation efficiency of the electron-hole pairs photo-generated with reasonable distribution density. These results are favorable for the improvement of photocatalytic performance. Compared to other nanocomposites, the 3-Au/CN sample (prepared using 3 mL HAuCl4 solution) with reasonable distribution density and small Au NPs exhibited the best photodegradation activity (92.66%) of RhB in 30 min under the visible light irradiation and photoreduction performance of CO2 to CO and CH4 with yields of 77.5 and 38.5 μmol/g, respectively, in 8 h under UV light irradiation. Considering the experimental results in the context of the literature, a corresponding size-dependent photocatalytic mechanism was proposed.

Supercapacitor is a new energy storage device between traditional capacitor and rechargeable battery. Not only has the characteristics of fast charging and discharging of capacitor, but also has the characteristics of energy storage of battery. The electrochemical tests indicate that the electrode in view of porous Ni2P2O7 nanowires (NWs) has a specific capacitance of 772.5 Fg-1 at current density 1 Ag-1. Furthermore, porous Ni2P2O7 NWs have been successfully applied to construct all-solid hybrid supercapacitors. Carbon nanotubes (CNT) and easily treated nickel pyrophosphate (Ni2P2O7) are considered as electrode materials for supercapacitors under alkaline conditions. The equipment has a high energy density of 6.25 mWh cm−2 and good cycle stability of 94% capacitance retention after 3000 cycles, which identifies that porous Ni2P2O7 nanowires are promising supercapacitor active materials.

A series of La2O3/CeVO4@halloysite nanotubes composites were successfully fabricated by the hydrothermal method. The La2O3/CeVO4@halloysite nanotubes composites display outstanding photocatalytic activity for removing tetracycline (TC) solution under visible light irradiation (λ ≥ 420 nm). After irradiation 60 min, an optimized La2O3/CeVO4@halloysite nanotube composite exhibited a high photocatalytic activity (87.1%), which is 3.89 times higher than that of raw CeVO4 (22.4%). The improvement of ternary composites performance is attributed to the Ce3+ and Ce4+ pairs in CeVO4. Besides, constructing heterojunctions between La2O3 and CeVO4 can inhibit the recombination of photoinduced electrons and holes, which is ascribed to the La3+ as electron trap to enhance the charge transfer. According to the trapper experiments and Electron Spin Resonance (ESR) analysis, the h+ and •O2− are major reactive species during the degradation. In addition, the oxygen vacancies are in the ternary photocatalyssts. The photocatalytic degradation intermediates of the solution were identified by High performance liquid chromatography-Mass spectra (HPLC-MS).

The development of highly efficient and long-term durable electrocatalyst for oxygen evolution reaction is still a great challenge to attain renewable and clean energy. Herein, CoSe2@N-Doped-carbon-nanorods named as CoSe2@NC nanorods have been conveniently synthesized by in-situ selenization of a novel N-doped metal organic frameworks under N2 atmosphere . CoSe2@NC nanorods show highly efficient electrocatalytic performance for oxygen evolution reaction at a low overpotential of 310 mV for 10 mA cm−2 current density in 1.0 M KOH aqueous solution, which are comparable to the state-of-the-art RuO2 and IrO2 catalysts. The remarkable electrocatalytic performance can be attributed to the unique N-doped MOFs derived well-defined architecture with large active surface area, high conductivity of carbon and well-distributed active sites. In addition, CoSe2@NC nanorods exhibit long-term stability without obvious decay after 1000 cyclic voltammetry cycles.

We have employed the first-principles calculations and quasi-harmonic Debye model to investigate the effect of the pressure on anisotropic elasticity and thermodynamic properties of FeAl3. According to Christoffel’s equation, the wave velocity anisotropy of FeAl3 as a function of pressure was also studied. Based on 3D surfaces and 2D projection contours, the anisotropy of shear modulus for FeAl3 changes significantly with the increasing pressure, and increases more obviously on [0 0 1] direction than that on [1 0 0] direction under high pressure. The thermodynamic properties calculations show that the volume of FeAl3 decreases with the increasing temperature and pressure. The bulk modulus decreases with the increasing temperature, and increases with the increasing pressure. On the contrary, the thermal expansion coefficient, the heat capacities, and Gruneisen constant increase with the increasing temperature, and decrease as pressure increases. It is found that the bulk modulus and Gruneisen constant display strong pressure dependence, while the heat capacities are sensitive to the temperature. And the thermal expansion coefficient is affected simultaneously by the pressure and temperature.

In this paper, an optical space–time shift-keying (OSTSK) scheme based on the space–time dispersion matrix block of orthogonal design and laser selection technology is proposed to improve the transmission bits per symbol (TBS) and bit error rate (BER) performance of the traditional optical space shift keying (OSSK). The average BER of OSTSK is investigated over the Gamma–Gamma channel and simulated using the Monte Carlo method. The results show that the proposed scheme has the highest TBS and best BER performance compared with OSSK and optical generalized space shift keying. In addition, we propose a threshold judgment orthogonal matching pursuit (TJ-OMP)-decoding algorithm near-optimal detector for the OSTSK scheme to reduce the computational complexity of the system. For the OSTSK system with N t = 4 and N r = 4 , when the reasonable threshold is selected as θ = 1.5 , the computational complexity of OSTSK-(TJ-OMP) is 74.3% lower than that of the OSTSK-maximum likelihood sequence detection (OSTSK-MLSD), while the signal-to-noise ratio of the OSTSK-(TJ-OMP) decreases by about 1.5 dB at B E R = 1 × 10 − 3 .

Optical spatial modulation (OSM), a recent optical multiple-input multiple-output transmission scheme in wireless optical communication, has aroused great research interests. OSM scheme requires accurate channel state information (CSI) during transmitter and receiver sides, but it is difficult to accurately estimate CSI in OSM scheme. Therefore, a scheme named differential optical spatial modulation scheme with pulse position modulation (DOSM-PPM) based on the space-time mapping block of orthogonal design is proposed in order to completely avoid CSI estimation. The bit error rate (BER) performance of DOSM-PPM is analyzed under log-normal turbulent channel model and simulated using Monte Carlo method. The results show that the transmission rate of DOSM-PPM is improved effectively. Meantime, the proposed DOSM-PPM scheme outperforms DOSM scheme with spatial pulse amplitude modulation by 1 dB at 1 × 10 − 3 BER with the same spectrum efficiency.

Device simplification is of practical significance for organic light emitting diodes (OLEDs), and remains the great challenge for deep-red emitters. Herein, a deep-red thermally activated delayed fluorescence molecule (pTPA-DPPZ) is reported which features a T shaped structure containing two triphenylamine (TPA) donors, one either side of a planar dipyridophenazine (DPPZ) acceptor. The rational spatial arrangement of the functional groups leads to limited but sufficient molecular packing for effective carrier transport. The neat pTPA-DPPZ film achieves an around 90-fold improved radiation rate constant of 107 s-1 and the nearly unitary reverse intersystem crossing (RISC) efficiency, as well as accelerated emission decays for quenching suppression. The high radiation and RISC result in a photoluminescence quantum yield of 87 %. The bilayer OLED based on the pTPA-DPPZ emissive layer achieved the record external quantum efficiencies of 12.3 % for maximum and 10.4 % at 1000 nits, accompanied by the deep-red electroluminescence with the excellent color purity.

In this paper, a series of novel dithioacetal-naphthalenes were designed and synthesized for plant immunity. Their antiviral activities were evaluated against tobacco mosaic virus (TMV) and cucumber mosaic virus (CMV). The results indicated that most compounds exhibited better activity against CMV than against TMV. These dithioacetal derivatives also displayed good bacterial activity against rice bacterial leaf blight. Among them, compound S16 exhibited relatively good anti-CMV, anti-TMV, and antibacterial activity. Structure-activity relationships indicated that introducing the naphthalene moiety enhanced their activities for plant resistance induction. Therefore, the basic motif of compound S16 could be the most promising candidate for further structural optimization to develop a potential activator for plant resistance induction.

Developing efficient red thermally activated delayed fluorescence (TADF) emitters is a real challenge due to the serious nonradiation of their low-band-gap singlet charge transfer state. Dipyridophenazine (DPPZ) (weak electron-withdrawing pyridines fused with strong electron-withdrawing phenazine) is used as an acceptor to overcome this issue. The gradient multi-inductive effect of different heterocyclic units simultaneously enhances the intramolecular charge transfer for red emission of the TADF molecule oTPA-DPPZ, and facilitates the radiative transition of its singlet charge transfer state by increasing frontier molecular orbital overlap on the electron-deficient pyrazine moiety. The 10-fold increased oscillator strength of its singlet transition results in its excellent photoluminescence and electroluminescence quantum efficiencies of ∼75% and ∼19%, accompanied by red emission peaked around 600 nm.

Environmentally friendly photodegradation of refractory pollutants utilizing semiconductor photocatalysis evolution exhibits satisfactory efficiency and low energy consumption, but some of its unbefitting band position largely limits practical applications. The controllable band structure tuning via coupling low-dimensional materials with enormous potential in semiconductor photocatalysis, notably attractive carbon quantum dots (CQDs) induced for a better utilization of low-energy photoexcitation of promising inherent optical properties and photocatalytic performance on organic pollutant degradation. Here, a CQDs modified ZnO hybrid materials was synthesized and the CQDs preluded carbon-incorporated burger-like ZnO nanoparticles clusters were presented thus demonstrated a specific doping-effect. The dispersity improved by loading halloysite nanotube (HNTs) for efficiently photocatalytic activity enhancement. Furthermore, the band structure, excitation and photocatalytic reactive oxygen species (ROS) generation were detected to reveal the photochemical properties and plausible mechanism of CQDs hybrid nanomaterials system. It is observed that the superoxide radical (O2 −), and singlet oxygen(1O2) are the principal ROS agents under UV–vis excitations. This work not only displays a CQDs modified system of expanding photo-response range to visible light but also throws a way for quantum elemental incorporated on the influence of band-tuning for semiconductor- dominated photocatalysts.

Exfoliation of bulk graphitic carbon nitride (g-C3N4) into two-dimensional (2D) nanosheets is one of the effective strategies to improve its photocatalytic properties so that the 2D g-C3N4 nanosheets (CN) have larger specific surface areas and more reaction sites. In addition, poly-o-phenylenediamine (PoPD) can improve the electrical conductivity and photocatalytic activity of semiconductor materials. Here, the novel efficient composite PoPD/AgCl/g-C3N4 nanosheets was first synthesized by a precipitation reaction and the photoinitiated polymerization approach. The obtained photocatalysts have larger specific surface areas and could achieve better visible-light response. However, silver chloride (AgCl) is susceptible to agglomeration and photocorrosion. The PoPD/AgCl/CN composite exhibits an extremely high photocurrent density, which is three times that of CN. Obviously enhanced photocatalytic activities of PoPD/AgCl/g-C3N4 are revealed through the photodegradation of tetracycline. The stability of PoPD/AgCl/CN is demonstrated based on four cycles of experiments that reveal that the degradation rate only decreases slightly. Furthermore, •O2− and h+ are the main active species, which are confirmed through a trapping experiment and ESR spin-trap technique. Therefore, the prepared PoPD/AgCl/CN can be considered as a stable photocatalyst, in which PoPD is added as a charge carrier and acts a photosensitive protective layer on the surface of the AgCl particles. This provides a new technology for preparing highly stable composite photocatalysts that can effectively deal with environmental issues.

Poor qualities of ZnMgO thin films are likely to be obtained at higher Mg content, which can decrease the performance of ZnMgO-based devices. This study focuses on improving the qualities of ZnMgO thin films to increase the performance of CdTe solar cell. It is found that the rapid thermal annealing (RTA) treatment increases the crystallinity, eliminates defects and improves the conductivity of ZnMgO thin films. These are helpful to suppress the recombination caused by bulk and interface defects as well as to reduce the cell's series resistance. The Fermi level moves close to conduction band and both the conduction and valence band energy shift lower relative to band energy of CdSSeTe film after RTA, which could not only increase the built-in voltage but also enhance the electron transport and block the hole recombination. As a result, the efficiency of CdTe solar cells is enhanced when using the RTA-treated ZnMgO, with maxium power conversion efficiency reaching values of 15.7%, which are much higher than those of the cells with the as-grown ZnMgO (11.6%). RTA is proved to be one of the excellent methods to control the properties of ZnMgO for improving the performance of CdTe solar cell.

CdTe nanoparticles modifying leafy CdS homologous semiconductor heterojunctions on nitrogen-doped reduced graphene oxide with solar full spectrum response is synthesized by a simple hydrothermal method and solvothermal method, and investigate their photocatalystic degradation of 2,4-dichlorophenol (2,4-DCP). The obtained CdTe/CdS/N-rGO composites show stronger intensity of photocurrent and longer lifetime of photon-generated carrier than CdTe/CdS and raw CdS, especially by which 70% 50 mg/L 2,4-DCP could be decomposed under visible light irradiation within 6 h. These result from those CdTe nanoparticles have good optical absorption coefficient to effectively absorb more photons and form electronic traps on its surface atoms, and construct homologous semiconductor heterojunctions between CdTe and leafy CdS to change movement pathway of photogenerated charge carriers, further prolonging the lifetime of electrons and holes, and loading nitrogen-doped reduced graphene oxide (N-rGO) could not contribute to electrons transfer, but also provide more active sites to improve the whole photocatalytic ability. These are further confirmed by those that high-resolution transmission electron microscopy (HRTEM) shows that crystal lattices of CdTe and CdS are staggered and the diffuse reflectance spectra (DRS) demonstrated absorption edge of CdTe/CdS/N-rGO get tremendous improved, even ternary composites could response in solar full spectrum. The new approach may provide some inspirations for constructing homologous heterojunctions structure on materials as support with efficient photocatalytic performance.

A multiple transmission channels, heterojunction and 3D PCN/AgBr/rGO photocatalyst was successfully synthetized by introducing the reduced graphene oxide (rGO) covering AgBr onto the surface of 3D porous g-C3N4 (PCN). In PCN/AgBr/rGO, PCN as a semiconductor photocatalyst provides the 3D framework, the heterojunction was formed with AgBr particles and PCN, rGO promotes the electron transfer simultaneously and introduces a multiple transmission channels system to increase the active species. Thanks to the heterojunction formed between PCN and AgBr, resulting rapid separation of photo-generated e−/h+ at interface. The 3D PCN/AgBr/rGO nanocomposite exhibits excellent photocatalytic efficiencies for tetracycline (TC) up to 78.4% within 90 min and 2,4-dichlorophenol (2,4-DCP) up to 68.2% within 6 h. The photocatalytic rate of PCN/AgBr/rGO was much higher than 3D PCN (21%), AgBr particles (31%) and most of g-C3N4-based photocatalysts in TC degradation. Moreover, the PCN/AgBr/rGO shows high photocatalytic stability due to the significantly photocatalytic stability after four photo-degradation cycles. This study highlights the potential application of PCN/AgBr/rGO highly efficient waste water purification.

The purpose of this work designed hybrid-structured and plasma effect photocatalyst of Ag/In2O3/TiO2/HNTs via sol–gel and photo-reduction methods. The structures, morphologies, optical and photoelectric performances of as-prepared photocatalysts were characterized via XRD, TEM, XPS, BET, UV–vis DRS, PL and photocurrents. The photocatalytic activity was evaluated by degradation of TC. The results showed that the hybrid-structure and plasma effect can effectively cause the multi-transfer of electrons and increase the separation rate of electron and hole pairs which obtained high photocatalytic activity. The photocatalytic degradation processes reveal that O2− and h+ are major active species.

The construction of nonprecious metal electrocatalysts for OER in alkaline media is still a significant urgency. Herein, we develop the topotactic conversion of Cu(TCNQ) nanoarray into Mn(TCNQ)2 nanoarray by low-temperature cationic exchange. The as-made Mn(TCNQ)2 nanoarray exhibits a marvelous electrocatalytic activity with low overpotential of 306 mV to obtain current density of 20 mA cm−2 in 1.0 M KOH. Markedly, the 3D electrode shows long-term electrocatalytic stability as well. The present finding shows its potential practical application for OER.

For the first time, KBaGd(MoO4)3:Eu3+ phosphors were synthesized by sol-gel method and its structure, morphology and luminescent properties were characterized by means of X-ray diffraction (XRD), scanning electron microscope (SEM), excitation and luminescent spectra. The results show that shape and the particle size distribution of samples synthesized by sol-gel method were more regular and narrower than those synthesized by solid state method. Under the excitation of near UV light (395 nm), an intensive red emission band around 617 nm corresponding to the transition of 5D0→7F2 was observed. The effects of the dose of citric acid, pH value of precursor solution and concentration of Eu3+ ions on the morphology and luminescent properties of the samples were also analyzed. The phosphors show the highest emission intensity as the molar ratio of citric acid to metal ions (C:M) was 2:1, and the optimum concentration of Eu3+ was x = 0.8. The thermal stability of the KBaGd0.2(MoO4)3:0.8Eu3+ phosphor was investigated in the framework of crossover mechanism, and the activation energy was determined to be 0.264eV. Lastly, a red LED was fabricated using the as-synthesized phosphor and its luminescent performances were investigated.

The performance of multiple-input multiple-output wireless optical communication systems that adopt Q-ary pulse position modulation over spatial correlated log-normal fading channel is analyzed in terms of its un-coded bit error rate and ergodic channel capacity. The analysis is based on the Wilkinson’s method which approximates the distribution of a sum of correlated log-normal random variables to a log-normal random variable. The analytical and simulation results corroborate the increment of correlation coefficients among sub-channels lead to system performance degradation. Moreover, the receiver diversity has better performance in resistance of spatial correlation caused channel fading.

Measurements of density, viscosity and vapor pressure for binary mixtures of exo-tetrahydrodicyclopentadiene (JP-10) with isopropyl ether are reported at temperatures of (293.15, 298.15, 303.15, 308.15, and 313.15) K over the entire composition range. The excess molar volumes, viscosity deviation and excess Gibbs energies of activation for the binary systems were calculated from the experimental values and fitted with the Redlich–Kister equation. Isopropyl ether was added to enhance the vapor pressure of JP-10. Experimental vapor pressure data were correlated by the Antoine equation. Several semi-empirical equations were used to correlate the viscosity data. The McAllister equation gives relatively satisfactory results for the correlation. The experimental and correlated data could be used in the development of models for mixtures of hydrocarbons with oxygenates.

In this work, we reported one kind of photocatalytic and antibacterial materials, Ag/Ag 2 S/reduced graphene oxide (rGO), which prepared by the hydrothermal and UV-light-assisted reduction methods. The Ag 2 S nanoparticals were well dispersed on the surface of rGO as revealed by series of characterization. The obtained Ag/Ag 2 S/rGO photocatalyst showed excellent photocatalytic degradation efficiency of 87.6% for ciprofloxacin (CIP) under visible light irradiation and outstanding antibacterial activity for Escherichia coli ( E. coli ) which reached to 97.76% in 24 h. The trapping of active species showed that the hydroxyl radicals, holes and superoxide radicals played important roles in the photocatalytic degradation of CIP processes.

Construction of multi-interface contact step-scheme (S-scheme) photocatalyst is a promising pathway to achieve high-electron transfer efficiency for photocatalytic CO2 reduction. In this paper, g-C3N4 nanosheets were selected as the main photocatalyst, rod-like CeO2 (R-CeO2) with unique Ce4+→Ce3+ conversion property and rGO were loaded on the g-C3N4 surface to construct 2D-1D-2D sandwich photocatalyst. The yields of CO and CH4 were about 63.18 and 32.67 μmol/g after 4 h when the rGO/R-CeO2/g-C3N4 was used as catalyst, which were about 4 and 6 times higher than that of pure CN, respectively. Cyclic experiments proved that the composite had excellent photocatalytic and material stability. Photoelectrochemical tests showed that the construction of S-scheme electron transfer model and the introduction of rGO can great enhance the electron transmission and separation of photogenerated electron-hole pairs. CO2 adsorption test identified that the loading of R-CeO2 and rGO obviously enhanced the CO2 adsorption ability of pure g-C3N4. Density functional theory (DFT) calculations used to analyze the electron transfer path and the formation of the build-in electric field at the semiconductor interface. In-situ FTIR and 13CO2 element-tracer detection carried out to research the process of CO2 photoreduction. A possible multi-interface contact S-scheme electron transfer mechanism for enhanced CO2 photoreduction activity has been discussed.

Ternary metal layered double hydroxides (LDHs) have been widely used in supercapacitors (SCs) due to their polyvalent state and high electrochemical activity. In this study, Ga (III) doped NiCo layered double hydroxides (NiCoGa-LDHs) electrode material is prepared on carbon cloth (CC) by simple one-step hydrothermal method for the first time. The effects of Ga3+ with different molar ratios on the structure, morphology, crystallinity, ion transport mechanics and electrochemical properties of ternary LDHs electrode materials are systematically investigated. At Ga3+ = 1.0, the as-synthesized Ni1Co3Ga1-LDHs@CC exhibits a special electrochemical capacitance of 2012.5 F g-1 at 1 A g-1 with 57.7% capacitance retention observed at 5.0 A g-1. The synthesis and evaluation of the two bimetallic NiCo-LDHs and NiGa-LDHs are similar in order to demonstrate the performance improvement of gallium heterovalent substitution. And heterovalent substitution of gallium for cobalt ion and nickel ion is proved indirectly. An Asymmetric supercapacitors (ASCs) device is assembled with Ni1Co3Ga1-LDHs@CC as anode and mesoporous carbon (MPC) as cathode, providing a high energy density of 84.22 Wh kg-1 at a power density of 800.1 W kg-1, with excellent cyclic stability. This study provides a new way to improve the electrochemical performance and stability of ternary metal LDHs.

PNIPAM@ZnO/C composite photocatalyst was prepared by cross-linking polymerization technology with N -isopropylacrylamide used as functional monomer, N , N' -methylenebis (acrylamide) used as cross-linking agent, ammonium persulfate used as initiator, and 3-(trimethoxysilyl) propyl methacrylate used as surface modification reagent. The morphology, structure, electrochemical and photocatalytic properties of as-prepared samples were characterized via the serial tests. The temperature-response performances of PNIPAM@ZnO/C were evaluated by the photocatalytic degradation of tetracycline (TC) under different temperatures. The results show that the synthesized composite photocatalysts possess the excellent and switchable photocatalytic activity. The photocatalytic degradation activity of PNIPAM@ZnO/C is suppressed above the lower critical solution temperature (LCST), and it is enhanced below the LCST.

The influence of Cr-, Nb- and W-doping on the mechanical properties of C11 b MoSi 2 has been investigated using first-principles calculations. Firstly, the formation enthalpies of both C11 b - and C40-structured MoSi 2 with various doping concentrations are calculated and compared, revealing that the C11 b structure can retain good structural stability at low doping concentrations of Cr, Nb or W up to ∼9.2 at.%. Based on the calculated elastic constants, the elastic moduli, hardness and several thermodynamic properties of doped MoSi 2 have been further predicted. Cr-doping decreases the elastic moduli drastically and W-doping decreases the Debye temperature, while doping with Nb increases the B/G ratio and Poisson ratio significantly, leading to good ductility and strong metallic bonding. As revealed in the three-dimensional contours of the elastic moduli, Cr- and W-doping does not obviously affect the anisotropy of the Young's and shear moduli, but Nb-doping shows a remarkable influence. Finally, in order to clarify the doping effects, the electronic properties of doped MoSi 2 are further discussed, based on the analysis of the charge density and density of states.

Divergent responses of tree growth to climate change have been widely reported from the high altitude forests of the Northern Hemisphere. Here, we developed tree-ring width (TRW) and maximum latewo...

This study investigates the influence of climatic changes on the annual stream flow of the Nu (Salween) River, over the period from 1958 to 2004. While the flow of the Nu River is mainly influenced by precipitation, the role of temperature in governing stream flow appears to be increasing as the climate warms. The first principal component extracted from climatic data accounts for 52.5% of observed variance in stream flow over the period 1958–2004. A transition toward a warmer, more humid regional climate has been ongoing since the 1980s, as evidenced by increases in temperature, precipitation, and stream flow in the Nu River Basin. A continuing trend toward higher temperatures and more intense precipitation will likely lead to increased Nu River stream flow in the future. Synoptic climatology indicates a link between extremes in annual Nu River stream flow and anomalies in atmospheric circulation patterns such as the mid-latitude westerlies and the South Asian Summer Monsoon.

One of current ideal thought to reduce the recombination of photogenerated electrons and holes from semiconductors is constructing Multi-dimensional semiconductor-carbon (S-C) heterostructures. As well as acting to photo-degrade the organic contaminant and decrease the toxicity, β-In 2 S 3 is chosen as a potential semiconductors for photocatalysts. Relative good photocatalytic properties delivered on β-In 2 S 3 , however, the fast recombination of photogenerated charge carriers are often appeared, causing reduced further application. Carbon quantum dots (CQDs) involve the introduction of plasma effect into the zero-dimensional nanomaterials in order to arouse an effect: either promoting the charge carriers transfer or plasma energy conversion of the photo-excited CQDs. However, state of the two components also encompass the poor quantum yield existed in the CQDs by its serious agglomeration. Thereby, the delivery of extraordinary ballistic electrical and thermal conductivity on single-walled carbon nanotubes (SWNTs), have shown potential for use in a variety of semiconductors decorating application. Herein, we show that a novel CQDs@In 2 S 3 /SWNTs composite in the Multi-dimensional (3D) hierarchical superstructures with an enhanced photocatalytic efficiency. The ESR analysis and free radicals trapping experiments indicated that the O 2 • − and h + were the main active species for the photocatalytic degradation. The potential photocatalytic mechanism of the three components is discussed and the direction in the plasma effect exhibited in CQDs is also considered, with a particular focus on photocatalytic area.

In this work, thermo-responsive PNIPAM@AgBr/CSs composite photocatalysts were successfully fabricated by grafting method. The thermo-responsive composite photocatalysts were further characterized by SEM, EDS, XRD, FT-IR, DRS and PL, the results demonstrated that the surface of CSs was successfully loaded with AgBr and further grafted with PNIPAM, and the grafted PNIPAM not only obtained the thermo-responsive performance, but also synergistically enhanced visible light photocatalytic activity toward degradation of tetracycline (TC) antibiotics. The influenced factors of photocatalytic degradation were also investigated, the results showed that the dosage of PNIPAM and the reacted temperature were obviously affected the degradation rate of TC. Lastly, the photocatalytic degradation mechanism of as-obtained thermo-sensitive photocatalyst was also discussed in detail. This work might offer a way to obtain the intelligently composite materials for switchable photocatalytic processes.

The northern Tibetan Plateau has been subject to recent warming far above the global average. With few instrumental climate records available for this region before the 1950s, paleoclimatic reconstructions must be used to understand annual-to-centennial-scale climate variations and local climate response to large-scale forcing mechanisms. We developed a maximum latewood density chronology of Qinghai spruce (Picea crassifolia) from the southern slope of the Qilian Mountains, northern Tibetan Plateau. Based on the chronology, we reconstructed August–September temperature for 1780–2008. The temperature reconstruction model accounts for 39.7% of instrumental temperature variance from 1957 to 2008, successfully capturing the most recent warming. Superposed epoch analysis indicated a volcanic forcing for temperature, resulting in pulses of cooler conditions that can persist for 2–4 years. Tree-ring data indicated that warm-dry and cold-wet climate combinations mainly occurred in northern Tibetan Plateau...

The cellular antioxidant activity (CAA) assay is wildly used for quantifying antioxidant activities of foods and dietary supplements in vitro. Among various incubation and handling buffers used in different laboratories, the inconsistence in concentrations of ions, particularly calcium and magnesium, has somehow been neglected. We hired the Hank's balanced salt solution with or without calcium and magnesium to perform CAA assay in Caco-2 cells and HepG2 cells, evaluating the impacts of these cations. The absence of calcium and magnesium reduced intracellular ROS level and underestimated the CAA of quercetin, Trolox and catechin. The abnormally high extracellular calcium and magnesium can also produce inaccurate results. Hank's buffer is recommended to ensure the accuracy and reproducibility. It elucidates precautions must be taken on these cations' concentrations of the buffers while conducting CAA determinations on different types of cells and when comparing foods and beverages with various calcium/magnesium contents.

As a popular ingredient for western and traditional Chinese medicine, the root and rhizome of Chinese licorice (Glycyrrhiza uralensis Fisch.) is often administered in the form of a decoction. The protein nanoparticles (NPs) self-assembled during the process of decoction. A major constitutive protein (GLP) was purified and determined to have a molecular weight of 28 kDa with an N-terminal sequence of NPDGL IACYC GQYCW. Over 80% of the purified GLP self-assembled into spherical NPs with diameters of 74.1 ± 0.7 nm and ζ-potential of -24.3 ± 1.7 mV when boiled in Tris-HCl buffer (pH = 7.9, 20 mM) at 100 °C for 60 min. Each nanoparticle was estimated by the SEC-MALLS approach to be composed of approximately 23 protein molecules. The NPs and GLP showed low cellular toxicity upon four types of cells including MDCK, L-02, HepG2, and Caco2 cells, while the NPs promoted proliferation of normal hepatocytes by 67%. The NPs solubilized the insoluble astragaloside IV by encapsulation. The results suggest a great potential for GLP-NPs as a promising prototype of a type of drug vehicle, a novel source of bioactive nanomaterials from herbal proteins, as well as a new mode of function with herbal components.

Local Surface Plasma Resonance (LSPR) effect enhanced Z-scheme ZnO/Au/g-C3N4 micro-needles film (3-ZAC) has been prepared for the photoreduction of CO2 into CO under UV–vis light irradiation. Photoreduction experiments show that 3-ZAC has the excellent photocatalytic performance and reusability. The CO production can be achieved 689.7 μmol/m2 after 8 h reaction time, which is 4.5 higher than that of the pure ZnO film. 13C isotope test shows that CO is produced from CO2 by photoreduction. DFT calculations confirm that build-in electric field formed at g-C3N4/ZnO interface effectively promoted the electron transfer efficiency in Z-scheme interface. FDTD simulations prove that Au NPs not only act as electron-transfer bridge, but also as LSPR excited source to speed up the separation of electron-hole pairs. In-situ FTIR technique was used to investigate the CO2 photoreduction process. The above characteristics together maximize the electron transfer efficiency, which causes the material has enhanced photocatalytic performance.

Strategies by introducing chiral auxiliaries into the photoreactive substrate 1,4-dihydropyridines, an interesting diastereoselectivity of 2,3-dihydropyrroles in the process of photochemical ring contraction was observed. The diastereoselectivity of (2R,3R) and (2S,3S)-2,3-dihydropyrroles was related to the phenyl group and the chirality of C-4 in 1,4-dihydropyridines and similar to that of 1,4-dihydropyridines. The yields and diastereomeric excess of all obtained products supporting the experimental data were compared and discussed in theoretical calculations. A concise theoretical study was used to explain the diastereoselectivity observed in the photochemical ring contraction of 1,4-dihydropyridines to 2,3-dihydropyrroles.

A series of nebula-like ZnO/CeO2@HNTs heterostructure photocatalysts were synthesized via a novel one-step wet-calcination method for degradation of tetracycline (TC) under simulated solar irradiation. TEM, HRTEM, XRD, FT-IR, XPS, DRS, PL, PC, EIS and ESR techniques were applied for characterization of samples. And the potential structure of new photodegradation products was studied by HPLC–MS analysis. The characterization results revealed the enhanced photocatalytic activity of ZnO/CeO2@HNTs heterostructure photocatalysts due to the delayed recombination of photogenerated electron-hole pairs. Moreover, surface oxidation state analysis demonstrates that Ce3+ and Ce4+ states coexist in CeO2, which enhance the separation of electron-hole pairs though cerium oxide shifting between CeO2 and Ce2O3 under photocatalytic process. In addition, the effects of the calcinating temperature, the molar ratio of ZnO to CeO2 and the dosage of HNTs on photocatalytic activity of ZnO/CeO2@HNTs heterostructure photocatalysts were researched and the best possible values have been found. Furthermore, the photodegradation mechanism was systematically investigated by active species trapping experiment. It revealed that OH radicals play a little role while hole and O2− are the more major reactive species in the photodegradation process.