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The Ag-doped MoS2 was used as SERS substrate in various detections. This work offers a novel idea to synthesize low-cost ultrasensitive SERS substrates, which is expected to extend the applications of semiconduct materials in clinical diagnosis.

A novel organic-inorganic hybrid rear window layer (RWL) was constructed. The photoelectric balance of the hybrid RWL was improved by doping with 1T-phase WS2 (1T-WS2).

Perovskite solar cells (PSCs) have become a promising alternative to sustainable energy due to their high power conversion efficiency (PCE) and low-cost processing. However, the practical applications of PSCs are still limited by the trade-off between high performance and poor stability under operation. Here, a 2D@3D perovskite with quasi core-shell architecture linking the superiorities of both two-dimensional (2D) and three-dimensional (3D) perovskite is prepared through a novel upgraded antisolvent approach. The basic properties as well as the phase distribution and the charge transport behavior of the 2D@3D perovskite were systematically elucidated. A high PCE of 21.60% for 2D@3D PSCs is achieved due to the enhanced surface and grain boundaries passivation, improved energy level alignment and efficient holes transport. The 2D@3D perovskite device without encapsulation shows significantly improved stability at the room temperature (90% of initial PCE for 45 d with a relative humidity of 50%±5%) and relative thermal conditions (83% of initial PCE for 200 h under 85 °C). Compared with traditional 3D PSCs, it proved that such 2D@3D perovskite configuration is an effective architecture for enhancing efficiency and improving stability and therefore will facilitate the further industrialization of PSCs.

Surface-enhanced Raman scattering (SERS) has attracted extensive attention as an ultrasensitive detection method. However, the poor biocompatibility and expensive synthesis cost of noble metal SERS substrates have become non-negligible factors that limit the development of SERS technology. Metal chalcogenide semiconductors as an alternative to noble metal SERS substrates can avoid these disadvantages, but the enhancement effect is lower than that of noble metal substrates. Here, we report a method to co-modify MoS

Ternary noble metal–semiconductor nanocomposites (NCs) with core–shell–satellite nanostructures have received widespread attention due to their outstanding performance in detecting pollutants through surface-enhanced Raman scattering (SERS) and photodegradation of organic pollutants. In this work, ternary Au@Cu2O–Ag NCs were designed and prepared by a galvanic replacement method. The effect of different amounts of Ag nanocrystals adsorbed on the surfaces of Au@Cu2O on the SERS activity was investigated based on the SERS detection of 4-mercaptobenzoic acid (4-MBA) reporter molecules. Based on electromagnetic field simulations and photoluminescence (PL) results, a possible SERS enhancement mechanism was proposed and discussed. Moreover, Au@Cu2O–Ag NCs served as SERS substrates, and highly sensitive SERS detection of malachite green (MG) with a detection limit as low as 10−9 M was achieved. In addition, Au@Cu2O–Ag NCs were recycled due to their superior self-cleaning ability and could catalyze the degradation of MG driven by visible light. This work demonstrates a wide range of possibilities for the integration of recyclable SERS detection and photodegradation of organic dyes and promotes the development of green testing techniques.

Polycyclic aromatic hydrocarbons (PAHs) with carcinogenic, teratogenic and mutagenic properties are persistent organic pollutants in the environment. Herein, the novel multifunctional Fe

In the past few years, the power conversion efficiencies (PCEs) of perovskite solar cells (PSCs) have increased from 3.81 to 25.2%, surpassing those of all almost all thin films solar cells. For hi...

In this work, a biofiber was used as the natural polymer carrier to design a BiVO4 QDs/cellulose fiber composite for photocatalytic application. The biofiber was obtained from bamboo, which was green, abundant and short growth cycle in Asia. Naturally rich groups of biofiber provided many sites to absorb the Bi3+ to form the uniform distribution for BiVO4 QDs. Moreover, a series of results indicated the strong connection was formed between biofiber and BiVO4 QDs, which could increase the stability and electron transfer. Therefore, the new composite photocatalyst exhibited better stability and effectively photocatalytic activity. Moreover, the possible mechanism of synthesis and photocatalytic were discussed, which provided insight for synthesizing photocatalytic based on biomaterials.

A new paradigm for photocatalysts based on two different hierarchically structured honeycomb and porous cylindrical Au-ZnO heterostructures was successfully developed via a straightforward and cost-effective hydrothermal method under different preparation conditions, which can be promising for industrial applications. The photocatalytic performance of all as-prepared samples under the illumination of sunlight was evaluated by the photocatalytic degradation of rhodamine B (RhB) and malachite green (MG) aqueous solutions. The results show that the photocatalytic degradation efficiency of RhB and MG was 55.3% and 40.7% for ZnO, 95.3% and 93.4% for the porous cylindrical Au-ZnO heterostructure, and 98.6% and 99.5% for the honeycomb Au-ZnO heterostructure, respectively. Compared with those from the ZnO, the results herein demonstrate an excellent reduction in the photoluminescence and improvement in the photocatalysis for the Au-ZnO hybrids with different morphologies. These results were attributed not only to the greatly improved sunlight utilization efficiency due to the surface plasmon resonance (SPR) absorption of Au nanoparticles in the visible region coupled with the UV light utilization by the ZnO nanostructures and multi-reflections of the incident light in the pore structures of their interior cavities but also to the high charge separation efficiency and low Schottky barrier generated by the combination of Au nanoparticles and ZnO micromaterials. Moreover, the honeycomb Au-ZnO heterostructure had a high Au content, surface area and surface oxygen vacancy (OV), which enabled photocatalytic properties that were higher than those of the porous cylindrical Au-ZnO heterostructures. In addition, two different formation mechanisms for the morphology and possible photocatalytic mechanisms are proposed in this paper.

Organic carbonyl electrode materials are widely employed for alkali metal-ion secondary batteries in terms of their sustainability, structure designability and abundant resources. As a typical redox-active organic electrode materials, pyrene-4, 5, 9, 10-tetraone (PT) shows high theoretical capacity due to the rich carbonyl active sites. But its electrochemical behavior in secondary batteries still needs further exploration. Herein, PT-based linear polymers (PPTS) is synthesized with thioether bond as bridging group and then employed as an anode material for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). As expected, PPTS shows improved conductivity and insolubility in the non-aqueous electrolyte. When used as an anode material for LIBs, PPTS delivers a high reversible specific capacity of 697.1 mAh g-1 at 0.1 A g-1 and good rate performance (335.4 mAh g-1 at 1 A g-1 ). Moreover, a reversible specific capacity of 205.2 mAh g-1 at 0.05 A g-1 could be obtained as an anode material for SIBs.

Ternary noble metal-semiconductor nanocomposites (NCs) with core-shell-satellite nanostructures have received widespread attention due to their outstanding performance in detecting pollutants through surface-enhanced Raman scattering (SERS) and photodegradation of organic pollutants. In this work, ternary Au@Cu

In the past few years, the power conversion efficiencies (PCEs) of perovskite solar cells (PSCs) have increased from 3.81 to 25.2%, surpassing those of all almost all thin films solar cells. For high-performance PSCs, it is pivotal to finely regulate the charge dynamics and light management between perovskite and charge-transfer materials to balance the trade-off between optical and electrical properties. In this study, a hemispherical core-shell silver oxide (AgO

Surface-enhanced Raman scattering (SERS) and photoluminescence (PL) are important photoexcitation spectroscopy techniques; however, understanding how to analyze and modulate the relationship between SERS and PL is rather important for enhancing SERS, having a great effect on practical applications. In this work, a charge-transfer (CT) mechanism is proposed to investigate the change and relationships between SERS and PL. Analyzing the change in PL and SERS before and after the adsorption of the probe molecules on Nd-doped ZnO indicates that the unique optical characteristics of Nd3+ ions increase the SERS signal. On the other hand, the observed SERS can be used to explain the cause of PL background reduction. This study demonstrates that modulating the interaction between the probe molecules and the substrate can not only enhance Raman scattering but also reduce the SERS background. Our work also provides a guideline for the investigation of CT as well as a new method for exploring fluorescence quenching., Spectroscopy: rare earths help sensors focus on the necessities Sensors that use laser light scattering to detect molecular-scale changes to samples can be improved with a new substrate that naturally reduces background interference. Surface-enhanced Raman spectroscopy (SERS) setups typically use a combination of metal nanoparticles and fluorescent probes to capture vibrational signals from biomolecules including DNA. Ming Gao from Jilin Normal University in Siping, China, and colleagues now report a technique to keep probe emissions from interfering with SERS signals. To accomplish this, the team synthesized a neodymium-doped zinc oxide spiky nanostructures substrate. Spectroscopic measurements revealed that neodymium’s electronic properties enabled it to transfer photoexcited electrons to the probes. This charge transfer reduced the probe’s fluorescent intensity and simultaneously enhanced SERS emissions beyond that available on pure zinc oxide surfaces., This study provides a new way to naturally eliminate the SERS fluorescence background by doping with Nd ions. These fundamental discussions here provide a path to enhance Raman scattering and reduce the SERS background and a guideline for the investigation of CT and a new method for exploring fluorescence quenching.

In this work, we reported the tailored design of highly efficient Fe

Suzuki-coupling reaction was applied in this article to synthesize three Re(I) complexes of Re(CO)3(NN)Br, where NN = 2,9-di(4-methyl phenyl)-1,10-phenanthroline (Re-1), 2,9-di(3,5-(diphenyl)phenyl)-1,10-phenanthroline (Re-2), 2,9-di(4-(triphenylsilyl)phenyl)-1,10-phenanthroline (Re-3), respectively. The maxima of the photoluminescent spectra of Re-1 ∼ Re-3 in THF (10−5 mol/L) and aggregation state mainly center at ca. 400 nm and ca. 570 nm, respectively. The excited-state decay lifetimes of the powder samples were ca. 0.77 μs, ca. 1.30 μs and ca. 1.01 μs for Re-1, Re-2, and Re-3, respectively. These results suggest that Re-1 ∼ Re-3 have the aggregation-induced phosphorescent emission enhancement character. Furthermore, the density functional theory was applied at the B3LYP/(LANL2Dz+6-31G) level to theoretically analysize the character of the frontier molecular orbitals of Re-1 ∼ Re-3.

Here, a new three-dimensional (3D) multi-shell Fe3O4/SiO2/ZnO/ZnSe (FSZ-ZnSe) photocatalyst with a type II heterostructure was successfully produced by a convenient synthetic route. The amount of ZnSe particles can be regulated by varying the reactant concentration, and five kinds of FSZ-ZnSe samples (FSZ-ZnSe0, FSZ-ZnSe1, FSZ-ZnSe2, FSZ-ZnSe3 and FSZ-ZnSe4) were obtained. The photocatalytic performances of all as-prepared samples under UV and visible light irradiation were evaluated by the photocatalytic elimination of rhodamine B (RhB) aqueous solution. No matter which light source was used, the FSZ-ZnSe3 sample exhibited enhanced photocatalytic activity in comparison with other samples, benefiting from the sensitization of a proper amount of ZnSe particles, which not only facilitated the separation of photo-induced carriers but also extended the light absorption. Moreover, compared to visible light radiation, the FSZ-ZnSe3 sample under UV light showed remarkably enhanced degradation efficiency toward RhB base on the Z-scheme type transfer of photo-generated electron-hole pairs. The Z-scheme mechanism was confirmed using radical trapping experiments and hydroxyl radical ( OH) formation determination study. Meanwhile, the FSZ-ZnSe3 sample exhibited excellent magnetic response and high stability during the recycling photocatalytic experiments.

The designed synthesis of advanced ZnO heterostructures in a simple and mild way is of great significance, for the purpose of improving their photocatalytic performance and large-scale applications. Herein, a magnetic hierarchical microsphere Fe3O4@SiO2@ZnO@Au (FSZA) was successfully synthesized by multistep chemical methods, in which magnetic Fe3O4@SiO2 as core for the growth of ZnO nanorod-layer using microwave-assisted approach, followed by the functionalization of Au nanoparticles (NPs). Four FSZA microspheres (FSZA1, FSZA2, FSZA3, FSZA4) were controlled prepared by adjusting the concentration of the Au precursor for comparison. The as-prepared products were characterized SEM, TEM, XRD, VSM, N2-sorption, photocurrent and XPS techniques. The results revealed that the as-synthesized microspheres have a good monodispersity, uniform core-shell structure and high magnetization. The photocatalytic test indicated the FSZA3 product possessed the best activity among all tested products, and the photodegradation rate of rhodamine B (RhB) reached 93.54% after UV irradiation of 80 min. The enhanced activity of FSZA3 was ascribed two major contributions, which were the larger specific surface area and the improved separation efficiency of the photogenerated carriers. The decomposition mechanism was discussed in detail. Additionally, such integrated FSZA3 photocatalyst was easily recovered by a magnet, which was reused at least five times without any appreciable reduction in photocatalytic efficiency.

In this study, we introduced an ordered metal–semiconductor–molecular system and investigated the surface-enhanced Raman scattering (SERS) effect. The carrier distribution and density can be easily monitored by changing the thickness of the Cu2S film on the surface of the Ag monolayer under different laser excitations. Meanwhile, different laser wavelengths were selected for investigating the enhancement mechanism of the system based on the viewpoint of the number of carriers and changes in the excitation energy. During this process, we found that the SERS peaks located at 1586 cm–1 changed significantly because the intensity can be “borrowed” from exited transition and the molecule-to-semiconductor transition. In combination with the theories of Albrecht and Lombardi, this phenomenon was analyzed in detail, and the experimental results and theoretical research match well. This research regarding the semiconductor-based SERS substrates will expand the basic theory of SERS enhancement and provide a theoret...

Novel multifunctional ZnO@ (Fe3O4/ZnS:Mn2+) nanocomposites as a pH-responsive drug delivery system were designed and successfully synthesized by a self-assembling method. The as-prepared ZnO@(Fe3O4/ZnS:Mn2+) possess porous hollow structure with strong orange fluorescence and faster magnetic response, which is beneficial for the functions of drug loading, fluorescence labeling and magnetic targeting simultaneously. Both in vitro and in vivo experiments testify that the ZnO@(Fe3O4/ZnS:Mn2+) nanocomposites own a good biocompatibility without obvious side effects on both cells and mice. After 24 days of treatment on the mice, ZnO@(Fe3O4/ZnS:Mn2+) nanocomposites greatly inhibited the tumor growth without causing both body weight change and any obvious pathological changes in major organs. The better antitumor efficacy than free DOX can be ascribed to both the accumulation of DOX-ZnO@(Fe3O4/ZnS:Mn2+) inside tumor and a sustained DOX release due to the dissociation of ZnO@(Fe3O4/ZnS:Mn2+) in acidic environment. Keywords: Zinc-based nanoplatform, pH-responsive, Drug delivery, Multifunction

Zinc ferrite nanomaterials have been received significant attention in recent years on account of their potential applications in the fields of electronics, optoelectronics and magnetics. To enhance the magnetic properties of zinc ferrites, Nd-doped zinc ferrites (ZnFe2−xNdxO4, x = 0, 0.01, 0.02, 0.03) nanoparticles (NPs) have been prepared by the sol–gel method. The effects of Nd doping concentration on the structural and magnetic properties of zinc ferrites were studied. The results of X-ray diffraction, scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy indicated that the Nd ions were incorporated into the crystal lattice of ZnFe2O4 and substituted for the Fe3+ sites. Unlike pure zinc ferrites with paramagnetism, Nd doped ZnFe2O4 NPs were superparamagnetic at room temperature. Vibrating sample magnetometry results showed, with the increase of Nd content, the saturation magnetization of Nd doped ZnFe2O4 NPs increased.

Magnetite Fe 3 O 4 nanoparticles (NPs) have attracted much interest due to their low toxicity, good biological compatibility and fast response to an external magnetic field. The magnetite Fe 3 O 4 NPs with different shapes and sizes were successfully prepared by the thermal decomposition method. The effects of the amount of solvent and the reaction time on the morphologies and the magnetic properties of magnetite Fe 3 O 4 NPs were investigated comprehensively. A series of testing methods including X-ray diffraction (XRD), Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS) and Mossbauer spectrum testified that the as-obtained samples were pure magnetite phase. Scanning electron microscopy (SEM) and transmission electron microscope (TEM) indicated the amount of solvent and the reaction time could tune the shape and size of Fe 3 O 4 NPs. The truncated cube and octahedron were the intergradations for the cube. The oleic acid played an important role in inhibiting the crystal growth along the 〈100〉 direction and accelerating that along the 〈111〉 direction of magnetite. The variation trend of the saturation magnetization ( Ms ) was in agreement with that of the particle size, which was attributed the contribution from the small-size effect or surface effect. The variation of the coercivity ( Hc ) depended on that of the magnetic anisotropy, the surface anisotropy or the shape anisotropy.

The Fe

This work focused on the utilization of biological extract for the preparation of lignin-based carbon composites materials and used in the field of photocatalysis. A straightforward one-step carbonization way has been developed to prepare vanadium-doped lignin-based carbon/Bi

A commercial SERS substrate does not only require strong enhancement, but also can be reused and recycled in actual application. Herein, Fe3O4/SiO2/ZnO/Ag (FSZA) have been synthesised, which consisted of Fe3O4 core with strong magnetic field response and an intermediate SiO2 layer as an electronic barrier to keep the stability of magnetite particles and outer ZnO and Ag as the effective layers for detecting pollutants. The SERS enhancement factor (EF) of the FSZA was ~8.2 × 105. The enhancement mechanism of the FSZA core-shell microspheres were anatomized. The electromagnetic enhancement of surface deposited Ag, charge transfer, and molecular and exciton resonances act together to cause such high enhancement factors. For practical application, the FSZA core-shell microspheres were also used to detect thiram, moreover, which was collected and separated by an external magnetic field, and maintained the SERS activity without significant decline during multiple tests. So the good enhancement performance and magnetic recyclability make the FSZA core-shell microspheres a promising candidates for practical SERS detection applications.

The diverse defects within perovskite film, electron transport layer (ETL) and their interface greatly impair the power conversion efficiency (PCE), hysteresis and stability of perovskite solar cells (PSCs). Herein, we propose a synchronous defect passivation strategy by introducing chelating agent containing movable alkali metal cations, i.e. sodium tartrate (STA)/potassium sodium tartrate (PSTA) into SnO2 aqueous colloidal dispersions to realize the efficient regulation of ETL, perovskite layer and their interface properties. That is, the chelating function and existence of alkali metal ions in additives lead to uniform, less defective and highly conductive SnO2 ETLs, which provides outstanding platforms for depositing perovskite films with high-quality crystallinity to improve the interfacial charge transfer. In particular, a part of Na+ and K+ ions of additives can enter into perovskite film through thermal diffusion and passivate the defects by coordinating with under-coordinated halides via ionic interactions or electrostatic adsorption on the negative charged defects at surface and grain boundaries. Such synchronous optimization for ETLs, perovskite and their interface enables the realization of high PCEs of 20.38% and 21.14% with reduced hysteresis and improved stability for STA-SnO2 and PSTA-SnO2 based PSCs, respectively. This work greatly simplifies the defect passivation process and provides a promising low-cost technique for large-scale manufacturing efficient and stable planar PSCs.

4-(4-(1,2,2-triphenylvinyl)phenyl)benzoic acid (TPEPhCOOH) with Zn2+ ion induced solution emission (CISE) character was synthesized. The freshly prepared TPEPhCOOH film has the fluorescence (FL) at ca. 498 nm with the excited-state decay lifetime of 2.98 ns and the absolute luminescence quantum yield of 64.8%. The FL studies on the non-radiative TPEPhCOOH/THF solutions with different metal ions suggest that TPEPhCOOH could radiatively response to the presence of Zn2+ ions. The aggregation-induced emission character of TPEPhCOOH in the mixed water/THF solvent (ca. 10−5 mol/L), along with the molecular dynamic and the quantum mechanic calculations, suggests that the Zn2+ CISE of TPEPhCOOH should originate from the coordination between Zn2+ ions and the TPE moiety of TPEPhCOOH.

Recently, the rapid improvement in power conversion efficiency (PCE) of perovskite solar cells (PSCs) with surprising and efficient PSCs is considered to be the most promising alternative to the next generation photovoltaic. In PSCs, the interfacial charge transfers between perovskite and electron transporting layers (ETLs) play an important role in enhancing the PCE, hysteresis, and stability. Here, an amorphous WOx (a-WOx) interlayer is interposed between the perovskite layer and mesoporous TiO2 (m-TiO2) layer to boost the hetero-interface charge transport. The room-temperature processed a-WOx has a wide bandgap and high electron mobility, which is capable of efficiently transporting photo-generated electrons, thereby reducing interfacial charge accumulation in the PSCs. Besides, we first found that the m-TiO2/a-WOx hybrid ETLs have better non-wettability, which subsequently improves the crystallization of the perovskite films by promoting the grain boundary mobility. Consequently, under optimized MAPbI3 solar cells having m-TiO2/a-WOx hybrid ETLs exhibits the highest Voc of 1.16 V and the PCE of 20.98%. Stability tests indicate that the PCE value based on the m-TiO2/a-WOx device remains more than 91% after exposure to 45% humidity for 30 days in the dark at room temperature, much higher than the m-TiO2 based cell, which retains about 70% of the initial PCE value.

In this work, we reported the tailored design of highly efficient Fe3O4-Au magnetic nanocomposite (MNP) catalysts. Fe3O4 nanocrystals with three different morphologies have been developed with engineered amounts of urea, and the plausible mechanism has been proposed. Then by controlling the amount of Au seeds, Fe3O4-Au MNPs with different morphologies and tunable Au deposition have been realized. Characterizations including x-ray diffraction (XRD), transmission electron microscopy (TEM), Mossbauer spectra, and elemental mapping are implemented to unveil the structural and physical characteristics of the successfully developed Fe3O4-Au MNPs with different morphologies. The catalytic ability of Fe3O4-Au MNPs with different morphologies have been compared by applying them to degrading RhB and 4-NP, meanwhile the correlation between the amount of Au seeds and the turnover frequency as well as the catalytic ability of Fe3O4-Au MNPs is investigated systematically. We found that the flower-like Fe3O4-Au MNPs with 20 ml Au seeds added achieved the best degradation efficiency of 96.7%, and their catalytic ability were almost unchanged after recycling. Out study sheds the light into the tailored design of highly efficient and recyclable catalysts for RhB and 4-NP.