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The fabrication of functional wound dressing for effective hemostasis, anti-inflammation as well as angiogenesis is of vital importance. In this paper, a three-dimensional (3D) nanofiber sponge with dimethyloxaloglycine (DMOG) loaded mesoporous spheres of derivatives of Prussian blue analogues (PBAs) was prepared (3D-PBAFeCo-DMOG). The nanostructure, composition, and mechanical properties of 3D-PBAFeCo-DMOG were characterized, showing regular nanostructure and good mechanical property. The behavior of in vitro drug release showed the DMOG could achieve long-term and stable release by encapsulating in PBAFeCo microspheres and nanofibers. In vitro coagulation experiments showed that 3D-PBAFeCo-DMOG had effective hemostasis and clotting capacities. In addition, the antioxidant capacity and cell compatibility of 3D-PBAFeCo-DMOG were confirmed. These results indicate that 3D-PBAFeCo-DMOG nanofiber sponge, as a controlled drug release system, may provide a new strategy for promoting angiogenesis and wound healing for clinical applications.

Perovskite materials with excellent optical and electronic properties have huge potential in the research field of photodetectors. Constructing heterojunctions and promoting carrier transportation are significant for the development of perovskite-based optoelectronics devices with high performances. Herein, we demonstrated a CsPbBr3/SnO2 heterojunction photodetector and improved the device performances through post-annealing treatment of SnO2 film. The results indicated that the electrical properties of SnO2 films will make an important impact on carrier extraction, especially for type-II heterojunction. As the electrons transfer layer in CsPbBr3/SnO2 type-II heterojunction, defects related to oxygen vacancy should be the key factor to affect carrier concentration, induce carriers’ limitation and recombination rate. Under proper annealing temperature for SnO2 layer, the recombination rate can decrease to 1.37 × 1021 cm3 s and the spectral responsivity will be highly increased. This work can enhance the understanding on the photoresponse of perovskite photodetectors, and will be helpful for the further optimization and design of optoelectronic devices based on the perovskite heterojunction.

Electrochemical sensing provides a new way for miniaturization and low cost of equipment. Meanwhile, digital microfluidic (DMF) technology is making lab-on-chip a reality. The two technologies are essential in the point-of-care area. Electrochemical detection on electrodes and DMF-based droplet driving electrode realize their respective functions by means of electrical signals. In terms of working mode, it seems to have certain similarity, and electrochemical sensing seems to be more suitable for integrating digital microfluidic systems. We thus integrated electrochemical sensing on an active matrix (AM) DMF system. As a common transparent conductive glass, indium tin oxide (ITO) has been widely used as the top plate of the digital microfluidic chip. In this work, we used ITO glass with patterned interdigital electrodes as the top plate of the AM-DMF chip. We achieved on-chip droplet volume detection by electrochemical impedance spectroscopy (EIS). We also proposed a novel sample dilution method on the DMF chip. It takes only 30 seconds to dilute solutions into 4 different concentrations. We then analyzed droplet samples of different concentrations with EIS method. And the correlation coefficient of the fitted curve is as high as 0.9964. In conclusion, EIS is a powerful detection technology for fast, high-integration and low-cost detection on DMF system. The integration of EIS and DMF can be used in various biochemical analyses in the future.

The development of tin-based perovskite solar cells (PSCs) is a promising approach to meet the demand of eco-friendly, lead-free perovskite photovoltaics. Limited to the poor chemical stability of tin perovskites, tin-based PSCs usually have to be fabricated with an inverted device structure and both the device efficiency and stability are highly dependent on the selection of hole transport materials (HTMs). Here, we report the synthesis of inorganic nickel oxide (NiO x ) nanoparticles (NPs) via a soft base precipitation method, which enables us to obtain highly dispersed NiO x NPs over a wide pH window. The as-prepared NiO x NPs are employed as the HTM for formamidinium tin iodide (FASnI3) PSCs, resulting in excellent device efficiency (∼8%) and stability (1200 h). Our study offers a facile strategy for mass production of NiO x NPs and easy access to efficient and robust inorganic HTMs that could further boost the development of high performance tin-based PSCs.

This paper makes an in-depth study and analysis of the direct carbon footprint of residents’ consumption in Inner Mongolia Autonomous Region based on the IPCC method and the decomposition model of the Logarithmic Mean Divisia Index (LMDI) from 2000 to 2016. The results show that 1) The overall consumption of urban residents and the direct carbon footprint per capita in Inner Mongolia Autonomous Region from 2000 to 2016 were much higher than that of rural residents. 2) The consumption of residents was closely related to the energy structure, and coal, heat and electricity consumption occupied the main position. 3) According to the analysis of the LMDI decomposition model, the energy structure factors contributed negatively to the direct carbon footprint of residents except 2003-2006. 4) Energy efficiency and economic development are important factors to stimulate the direct carbon footprint of residents. Finally, we provide reasonable suggestions for residents’ consumption, energy saving and emission reduction.

Single crystals of methylammonium lead trihalide perovskites have been widely applied in the research of next-generation photodetectors due to their remarkable light-harvesting properties, low trap density, and good carrier transport ability. Herein, the presented work demonstrates the high-quality and millimeter-scale single crystals CH3NH3PbBr3 and CH3NH3PbI3 perovskite-based planar photodetectors modified by ITC technique. The highest photoresponsivity of CH3NH3PbBr3 photodetector can reach 111 A/W under the visible illumination of 520 nm light and the highest photoresponsivity of CH3NH3PbI3 photodetector can reach 568 A/W under the infrared illumination of 895 nm light. The photodetectors also demonstrate the high on/off ratio and fast response speed. It implies that CH3NH3PbBr3 and CH3NH3PbI3 single crystals based photodetectors reveal great attention for the application of the Vis-NIR photodetection.

A plasmonic interferometer consisting of a T-shape patterned semiconductor is investigated in THz regime. The microslit couples incident THz radiation into unidirectional SPPs waves, which are reflected by bilateral sidewalls and interfere with directly transmitted THz wave. The phase/amplitude of interfering SPPs waves can be effectively engineered by structural tuning, offering a flexible and efficient control over the shape of interference pattern. Spectral fringes with large amplitude and high-contrast have been demonstrated and permit Figure-of-Merit for intensity detection (wavelength sensitivity) up to 15255%RIU^-1 (160 um/RIU). The results could be promising for developing ultrasensitive biosensors and on-chip platforms.

In this paper, a centimeter-scale monolayer molybdenum disulfide (MoS2) film deposition method has been developed through a simple low-pressure chemical vapor deposition (LPCVD) growth system. The growth pressure dependence on film quality is investigated in this LPCVD system. The layer nature, electrical characteristic of the as-grown MoS2 films indicate that high quality films have been achieved. In addition, a hydrofluoric acid treated SiO2/Si substrate is used to improve the quality of the MoS2 films. Piezoresistive strain sensor based on the monolayer MoS2 film elements is fabricated by directly patterning metal contact pads on MoS2 films through a silicon stencil mask. A gauge factor of 104 ± 26 under compressive strain is obtained by using a four-point bending method, which may inspire new possibilities for two-dimensional (2D) material-based microsystems and electronics.

Te-doped cadmium telluride (CdTe) films were deposited on ITO/glass substrates using the close spaced sublimation (CSS) method. The films were characterized by x-ray diffraction (XRD), the x-ray fixed-quantity (XRF) method, scanning electron microscopy (SEM) and the Hall effect. The XRD and SEM results show that appropriate Te doping would be favourable to the growth of CdTe crystallite. The Hall effect measurements indicate that the conductivity of CdTe films could be dramatically improved by Te doping. The work presented here suggests that p-type doping CdTe films can be produced using this deposition method.

Solar steam technology is one of the simplest, most direct and effective ways to harness solar energy through water evaporation. Here, we report the development using super-hydrophilic copper sulfide (CuS) films with double-layer structures as light absorbers for solar steam generation. In the double-layer structure system, a porous mixed cellulose ester (MCE) membrane is used as a supporting layer, which enables water to get into the CuS light absorbers through a capillary action to provide continuous water during solar steam generation. The super-hydrophilic property of the double-layer system (CuS/MCE) leads to a thinner water film close to the air-water interface where the surface temperature is sufficiently high, leading to more efficient evaporation (~80 ± 2.5%) under one sun illumination. Furthermore, the evaporation efficiencies still keep a steady value after 15 cycles of testing. The super-hydrophilic CuS film is promising for practical application in water purification and evaporation as a light absorption material.

A scanning probe with nitrogen vacancy (NV) centers in diamond thin film was fabricated via a standard micro/nano electromechanical system process. The diamond thin film was selectively grown by microwave plasma enhanced chemical vapor deposition on a partially nucleated silicon surface. NV centers are embedded during the diamond growth with a pure nitrogen gas flow to the growth chamber. The existence of NV centers in the diamond thin film was confirmed by photoluminescence measurements. In addition, we found that a xenon difluoride (XeF2) etching process and anneal treatment have an influence on the existence of NV centers in the diamond. The fabricated scanning probe with NV centers in diamond thin film can be used as a magnetic scanning sensor. It is anticipated that the alternative method of selectively growing diamond thin film provides various diamond structures in diverse applications.

From environmental and health perspectives, the acquisition of a surface anti-biofouling property holds important significance for the usability of VO2 intelligent windows. Herein, we firstly deposited amorphous Ta2O5 nanoparticles on VO2 film by the magnetron sputtering method. It was found that the amorphous nano-Ta2O5 coating possessed a favorable anti-biofouling capability against Pseudomonas aeruginosa as an environmental microorganism model, behind which lay the mechanism that the amorphous nano-Ta2O5 could interrupt the microbial membrane electron transport chain and significantly elevate the intracellular reactive oxygen species (ROS) level. A plausible relationship was established between the anti-biofouling activity and physicochemical nature of amorphous Ta2O5 nanoparticles from the perspective of defect chemistry. ROS-induced oxidative damage gave rise to microbial viability loss. In addition, the amorphous nano-Ta2O5 coating can endow VO2 with favorable cytocompatibility with human skin fibroblasts. This study may provide new insights into understanding the anti-biofouling and antimicrobial actions of amorphous transition metal oxide nanoparticles, which is conducive to expanding their potential applications in environmental fields.

Modulation instabilities in the randomly birefringent two-mode optical fibers (RB-TMFs) are analyzed in detail by accounting the effects of the differential mode group delay (DMGD) and group velocity dispersion (GVD) ratio between the two modes, both of which are absent in the randomly birefringent single-mode optical fibers (RB-SMFs). New MI characteristics are found in both normal and anomalous dispersion regimes. For the normal dispersion, without DMGD, no MI exists. With DMGD, a completely new MI band is generated as long as the total power is smaller than a critical total power value, named by Pcr, which increases significantly with the increment of DMGD, and reduces dramatically as GVD ratio and power ratio between the two modes increases. For the anomalous dispersion, there is one MI band without DMGD. In the presence of DMGD, the MI gain is reduced generally. On the other hand, there also exists a critical total power (Pcr), which increases (decreases) distinctly with the increment of DMGD (GVD ratio of the two modes) but varies complicatedly with the power ratio between the two modes. Two MI bands are present for total power smaller than Pcr, and the dominant band can be switched between the low and high frequency bands by adjusting the power ratio between the two modes. The MI analysis in this paper is verified by numerical simulation.

In this paper, different MgO films were deposited on a GaAs substrate by atom layer deposition (ALD), which can passivate the surface state of GaAs. From XPS results, the band structure of MgO/GaAs can be indexed to type I. Based on band alignment, the excitons could not diffuse and created nonradiative centers, which were all limited and then recombined at the MgO/GaAs interface, thus the emission intensity of the 100 nm MgO film coated sample was about 3 times higher than the uncoated sample.

Through a facile hydrothermal process and atomic layer deposition (ALD) technology, we obtained a kind of ZnO/ZnMgO core–shell nanowire array. The x-ray diffraction (XRD) results show a dominant (002) peak appears in as-grown ZnO, while the strongest peak is assigned an intensity of (100) in ZnO/ZnMgO core–shell structure. After ZnMgO shell coating, the main ultraviolet emission peak in room photoluminescence (PL) spectrum splits into two peaks, which locate at 364 nm and 378 nm. Furthermore, significant enhancement (one order of magnitude) in photoconductivity has been demonstrated. It is possible that the ZnMgO layer acts as an interfacial carrier transport layer, reducing the probability of carrier recombination.

High transparency and low resistivity aluminum-doped zinc oxide (AZO) films were prepared by atomic layer deposition. The AZO films show a transparency of about 80% in the near-infrared (NIR) region and a resistivity of the order of 10−3 Ω cm. Organic small molecule NIR-photodetectors (NIR-PDs) with AZO as the anode have been demonstrated for the first time with lead phthalocyanine (PbPc) and C60 as the donor and acceptor, respectively. The optimized NIR-PD exhibited an external quantum efficiency of 6.2% at 760 nm. This result indicated that AZO can be used as the anode for high efficiency NIR-PDs.

The damage introduction rates of BF2+, B+ and F+ ions implanted into (100) bulk silicon have been investigated over the energy range 3 to 13 keV amu-1 at temperatures of 77 K and 300 K. The samples have been analysed using 2 MeV He+ Rutherford backscattering and channelling, and it is found that the damage created by BF2+ molecular ions is significantly greater than that created by an equivalent dose of the atomic species B+ and F+. This damage enhancement by the BF2+ ions can be separated into bulk effects, which are due to displacement spikes, and surface effects, caused by multiple collision sequences involving the constituent particles (B and F) after dissociation of the incident BF2+ ion. Similar surface damage enhancements of 1.8 and 1.9 are found at 77 K and 300 K respectively, for particle energies of 3 keV amu-1. The energy dependence of the surface enhancement factor shows a strong dependence upon ion energy reaching a maximum of 3.5 at 8 keV amu-l but approaches unity at higher energies.

This paper reports on the preparation of a new multifunctional nanocomposite that consists of superparamagnetic core and rhodamine B (Rh B) doped silica shell. The final products were characterized by x-ray powder diffraction (XRD), transmission electron microscopy (TEM), vibration sample magnetometer (VSM), photoluminescence (PL) spectra and Fourier transform infrared spectra (FT-IR). The resultant multifunctional nanoparticles were superparamagnetic with a saturation magnetization of about 10 emu g−1, their sizes were smaller than 150 nm and they possessed an emission peak at 568 nm with an excitation wavelength of 520 nm. This new material holds considerable promise in magneto-optical materials and biological applications.