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In this work, a molecular weight-regulated efficient SD strategy is firstly employed to improve the performance of the ST-OSCs. More importantly, the light utilization efficiency (LUE) of 5.01% is obtained.

Purpose Phenolic epoxy vinyl ester resin (PEVER) is an advanced resin matrix, which has excellent heat resistance, electrical insulation. However, the brittleness and poor toughness of its curing product limited its application, so this paper aims to modify the PEVER with hyperbranched polyimide (HBPI), so as to enhance the toughness, heat resistance and dielectric properties of PEVER. Design/methodology/approach Hexamethylene diisocyanate trimer was used as the central reactant. Methyl tetrahydrophthalic anhydride was used as the branching unit, stannous octoate was used as the catalyst and hydroquinone was prepared as the inhibitor. Then, the hyperbranched structure of HBPI was characterized by Fourier transform infrared spectrometer and 13C-NMR. Next, PEVER was mixed with different contents of HBPI, and then the authors tested its curing product. Findings It is found that with the addition of HBPI, the free volume of the system was increased and the content of polar groups was decreased in each unit space, so the dielectric constant (ε) and the dielectric loss (tanδ) were decreased. In addition, PEVER could be well toughened by HBPI and the thermal stability of PEVER was improved. Originality/value HBPI has excellent heat resistance. The addition of hyperbranched polymer increases the free volume of the system so it can slow down the transfer of stress and its nearly circular structure can absorb the impact energy from all directions. Moreover, an appropriate amount of free volume can decrease the dielectric constant of PEVER by reducing the content of polar groups.

MXene is a neoteric type of bidimensional (2D) transition metal carbide/nitride with broad application prospects, in particular with electrochemical energy storage. The electrochemical performance of MXene is unsatisfactory because it is easy to stack resulting in the difficulty of electrolyte penetration and ion transport. In this study, the cobaltous sulfide-modified 3D MXene/N-doped carbon foam (CoS@MXene/CF) hybrid aerogel is projected and manufactured via simple in situ growth and thermal annealing strategies. The capacitance of the as-fabricated 300-CMC-31:1 electrode material reaches 250 F g-1 (1 A g-1), which is obviously higher than those of MXene, CoS@CF, 400-CMC-31:1, 300-CMC-10:1, 300-CMC-50:1, CF, and MXene/CF electrode materials. Moreover, it can hold 97.5% of the original capacitance after 10,000 cycles and the internal resistance (Rs) is only 0.50 Ω. A green bulb can be lit by two all-solid asymmetric supercapacitors installed in series. The prepared CoS@MXene/CF hybrid aerogel exhibits promising potential for practical application in energy storage areas.

Terpolymers have been proven to be promising polymer donors for organic solar cells (OSCs). However, the aperiodic sequence distribution caused by random copolymerization dramatically interrupts the orderly stacking of the conjugated main chain. In this work, we reported three terpolymers by introducing Si and Cl functionalized benzodithiophene (BDT-SiCl) into a polymer PM6 matrix with F functionalized benzodithiophene (BDT-2F) by random copolymerization. BDT-SiCl has the same skeleton as BDT-2F, but only differs in functional atoms on the side chain. The structural similarity of the two building blocks not only can minimize the disturbance of the molecular orderly packing caused by random copolymerization, but also can enhance the face-on orientation of the active layer to facilitate charge transport. Moreover, the alkylsilyl and chlorine atom enable the terpolymers to have a lower HOMO level and broadened light absorption compared to PM6. As a result, the terpolymer-based OSCs achieve the best efficiency of 16.22% with a small energy loss of 0.50 eV, yielding overall improved device parameters compared to PM6-based devices. In addition, thanks to the chemical bond linkage, the terpolymer-based device has a higher thermal stability than its corresponding ternary OSC. These results demonstrate that the design concept of structural similarity is a promising strategy to construct terpolymers for high-performance OSCs.

A low-cost and efficient hole transport layer (HTL) material (TPE-CZ) with the aggregation-induced emission (AIE) effect has been synthesized. Due to the AIE effect, perovskite solar cells with TPE-CZ as the HTL deliver a higher power conversion efficiency (PCE) of 18% with better stability than those with the reference HTL (Spiro-OMeTAD).

The rational design of admirably high-efficiency and relatively stable non-noble metal electrocatalysts is vitally important for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), particularly as bifunctional catalysts for overall water splitting. Herein, via a facile one-pot hydrothermal approach, high-performance bifunctional catalysts of Co3O4–CeO2 with pollen-petal-like heterostructures are synthesized in situ on 3D FeNi3 foam (FNF) (denoted as Co3O4–CeO2@FNF). In a 1.0 M alkaline aqueous solution of KOH, the designed Co3O4–CeO2@FNF with a large surface area exhibits both outstanding HER and OER activities, with an ultralow overpotential of 53.8 and 236 mV at 10 mA cm−2, respectively. Additionally, a standard two-electrode system fabricated by employing Co3O4–CeO2@FNF as both the cathode and anode shows an overpotential of 1.59 V at 10 mA cm−2 and moreover retains 93% of the activity after a 70 h long-term stability test. Moreover, the electron transportation is accelerated due to the increased density of states across the Fermi level resulting from oxygen vacancy doping, which further endows Co3O4–CeO2@FNF with outstanding catalytic performance. Furthermore, it should be noted that the designed catalysts could be manufactured on a large scale, which further envisions their promising commercial utilization for overall water splitting.

Most semitransparent organic solar cells (ST-OSCs) show a low open-circuit voltage (VOC) because of the inherent narrow band-gap of the active layer materials, which is proven to be a key limitation for the improvement of the device performance. To obtain a high VOC, wide-band gap polymer donors, such as PM6 are often selected for ST-OSCs, but the absorption in the visible light region of such wide-band gap polymer donors is not conducive to the transparency of the devices. Therefore, rational design of active materials to improve the VOC and device efficiency without sacrificing transparency is critical to realize ST-OSCs for practical applications. Herein, we propose a new design concept of combination of donors and acceptors with low energy levels and overlapping near-infrared absorption for high performance ST-OSCs. We incorporate chlorine, sulfur and fluorine functional atoms into the polymer PCE10 to down-shift the energy levels of the resulting polymer donors, namely PCE10-2Cl, PCE10-SF and PCE10-2F, respectively. All these functionalized polymer donors show lower energy levels than PCE10, ensuring a significantly higher VOC. Especially, the narrow band-gap PCE10-2Cl having overlapping absorption with the non-fullerene acceptor IT-4F not only obtains a remarkably improved VOC, but also achieves a comparable photocurrent to the blends with complementary absorption. Subsequently, the PCE10-2Cl:IT-4F-based device delivers a champion power conversion efficiency (PCE) of 10.72% among the functionalized PCE10-based devices. For the ST-OSC device with PCE10-2Cl:IT-4F, a PCE of 8.25% with an average visible transmittance (AVT) of 33% is achieved without any extra treatment, which is an outstanding performance of ST-OSCs with an AVT of over 30%. These results indicate that a rational combination of narrow band-gap donors and acceptors with overlapping absorption is a promising strategy to fabricate high performance ST-OSCs.

Both melatonin and ascorbic acid could perform an irreplaceable role in maintaining the ecological balance of the human body and fighting cardiovascular diseases. Herein, a dual-channel photo-assisted electrochemical sensor has been fabricated based on Au post-functionalized CeFeO

Although breakthroughs have been made in organic solar cells (OSCs) in recent years, the power conversion efficiency (PCE) of OSCs still lags behind inorganic/perovskite solar cells. In this work, two terpolymers were synthesized by introducing the thieno[3,4-c]pyrrole-4,6-(5H)-dione (TPD) block into the host polymer donor PM6. Owing to the lower highest occupied molecular orbital energy level, wider light absorption, optimal molecular packing, and more desirable aggregation morphology by addition of the TPD, the PM6-TPD-5 % : Y6-based device displayed an improved PCE of 16.3 % with an enhanced open-circuit voltage (V

Although ternary organic solar cells (OSCs) have unique advantages in improving device performance, the morphology assembly in the ternary-phase would be more uncertain or complex than that in the binary-phase. Here, we propose a new concept of oligomer-assisted photoactive layers for high-performance OSCs. The formed alloy-like phase of the oligomer : host polymer blend enabled the oligomer-assisted OSCs to fuse the advantages of both binary and ternary devices, exhibiting substantially enhanced performance and stability compared to the control devices. With the addition of oligomers, outstanding efficiencies of 17.33 % for a PM6 : Y6 device, 18.32 % for a PM6 : BTP-eC9 device, and 17.13 % for a PM6/Y6 pseudo-bilayer device were achieved, all of which are one of the highest values in their corresponding fields. The improved performance originated from the downshift energy levels, enhanced light absorption, optimized blend morphology, favorable charge dynamics, and reduced non-radiative energy loss.

In this paper, a polarization-insensitive reverse-ridge AlGaAs waveguide is designed for the supercontinuum generation. In the considered wavelength range from 3.4 to 8 μ m, the dispersion profiles, nonlinear coefficients, and effective mode field areas for the quasi-TE and quasi-TM modes coincide well. The simulation results show that when pump pulse with wavelength of 4.2 μ m, peak power of 4.8 kW, and width of 90 fs is launched into the anomalous dispersion region of the quasi-TE and quasi-TM modes of the 3.4-mm-long waveguide, the two generated SCs overlap well. For the quasi-TE and quasi-TM modes, the SCs generated extend from 2.17 to 8.53 μ m and 2.23 to 8.61 μ m, respectively, spanning more than 1.95 octaves. The proposed reverse-ridge AlGaAs waveguide structure is expected to provide a possible solution for alleviating the undesired polarization effect related to the nonlinear dynamics.

We propose the two-stage cascaded-tapered silica photonic crystal fiber (PCF) for the supercontinuum (SC) generation. The cascaded-tapered silica PCF is designed to have a spatial periodic structure. The physical scenarios of the spectral broadening due to the interaction between the structure-induced periodic dispersion and Kerr nonlinearity under different pulse widths and peak powers are investigated. It is found that when the pump pulses with width of

Unfused-ring acceptors (UFAs) show bright application prospects in organic solar cells (OSCs) thanks to their easy synthesis, low cost, and good device performance. The selection of central-core building block and suitable side chain are the key factors to achieve high-performance UFAs. Current tremendous endeavors for the development of UFAs mainly concentrate on obtaining higher short-circuit current density (J

In this paper, a reverse-strip AlGaAs waveguide with three zero-dispersion wavelengths (ZDWs) is designed. The corresponding three ZDWs are located at 3.74, 6.56, and 8.89 µm. The nonlinearity coefficient of the proposed reverse-strip AlGaAs waveguide is calculated as 2.09 W − 1 m − 1 at wavelength 4.9 µm. The effects of pump pulse parameters, waveguide length, and noise coefficient on the nonlinear dynamics of supercontinuum (SC) generation are investigated. When the hyperbolic secant pump pulse with a wavelength of 4.9 µm, peak power of 900 W, and duration of 100 fs is launched into the proposed waveguide and propagated after a 3 mm length, highly coherent and multi-octave mid-infrared (MIR) SC spanning from 2.2 to 14.5 µm (more than 2.7 octaves, at − 40 d B level) is generated. Finally, a possible fabrication process of the reverse-strip AlGaAs waveguide is introduced. Our research results have important applications in MIR photonics, MIR spectroscopy, optical precision measurement, and more.

The effects of iron oxide nanoparticles (IONPs, including Fe2O3 NPs and Fe3O4 NPs) on composting were investigated through evaluating their influences on organic matter (OM) degradation, dehydrogenase (DHA) and urease (UA) activities, and quality of the final compost product. Results showed that composting amended with Fe2O3 NPs was more effective to facilitate OM degradation. At the end of composting, the total OM loss in T-C, T-Fe2O3 NPs and T-Fe3O4 NPs was 66.19%, 75.53% and 61.31%, respectively. DHA and UA were also improved on the whole by the amendment of IONPs, especially Fe2O3 NPs. Although relationships between enzyme activities and environmental variables were changed by different treatments, temperature was the most influential to variations of both DHA and UA in all treatments, which independently explained 75.1%, 34.7% and 38.4% of variations in the two enzyme activities in T-C, T-Fe2O3 NPs and T-Fe3O4 NPs, respectively. Compared with DHA, UA was more closely related to the environmental parameters. The germination index in T-C, T-Fe2O3 NPs and T-Fe3O4 NPs was 134.49%, 153.64% and 146.76%, and the average shoot length was 3.16, 3.87 and 3.45 cm, respectively, indicating that amendment of IONPs, especially Fe2O3 NPs, could promote seed germination and seedling growth. Therefore, composting amended with IONPs was a feasible and promising method to improve composting performance, enzyme activities as well as quality of the final compost product.

Sulfide-modified nanoscale zero-valent iron (NZVI-S) has been considered as a promising material for in-situ chemical reduction processes (ISCRPs) for groundwater remediation. However, studies utilizing NZVI-S for in-situ chemical oxidation processes (ISCOPs) were relative rare. In this study, NZVI-S was synthesized and utilized to activate persulfate (PS) for the degradation of TCE. The effects of Fe/S molar ratio, initial pH on TCE removal and dechlorination by NZVI-S activated PS were studied. The results showed that, compared with bare NZVI, NZVI-S showed better properties in activating PS which included better pH adaptiveness, higher TCE removal and mineralization efficiency, and faster removal rate. The Fe/S molar ratio significantly influenced the TCE degradation, and the highest TCE degradation was observed at Fe/S molar ratio of 25–30. The underlying mechanisms of NZVI-S exceling NZVI in activating PS were elucidated through spectroscopic analyses that accounted for the higher iron dissolution rates and iron sulfides (e.g., FeS and FeSx) generated on its surface, which elevated the quantity and accelerated the transfer rate of electrons for activating PS. Besides, hydroxyl radical was observed as a dominant reactive radical in degrading TCE at various pH conditions, but sulfate radical also played an important part especially under acidic condition. Finally, the degradation products of TCE were analyzed and the possible pathways of TCE degradation were illustrated. And the slight influence of natural substances in groundwater on the degradation process suggests NZVI-S activated PS would be a promising approach for groundwater remediation.

In this paper, a slot SiC waveguide with four zero-dispersion wavelengths (ZDWs) is proposed for the supercontinuum (SC) and frequency comb generations. The four ZDWs are located at 1089, 1656, 2222, and 3113nm, respectively. The effects of the pump wavelength, peak power, pulse width, and waveguide length on the SC generation are discussed when the waveguide is pumped near the first ZDW and the third ZDW in the anomalous dispersion region, respectively. While pumping at 1300 and 2450nm, a near-infrared SC covering from 873 to 2444nm and a mid-infrared SC extending from 1349 to 4727nm with good coherences are obtained, respectively. By utilizing a 50-pulses pump source at a repetition rate of 1GHz, we also investigate the SC-based frequency comb generation.

In this paper, a T-type germanium (Ge) waveguide with an all-normal dispersion profile is designed for mid-infrared (MIR) supercontinuum (SC) and frequency comb generations. The nonlinearity coefficient of the designed waveguide is calculated as 30.48 W-1·m-1 at the initial pump wavelength of 3.0 µm. Moreover, the group-velocity dispersion is kept low and flat in the considered wavelength range. Simulation results show that with the designed waveguide, the highly coherent and octave-spanning MIR SC can be generated in the wavelength range from 1.85 to 9.98 µm (more than 2.4 octaves) when the pump pulse with wavelength of 3.0 µm, peak power of 900 W, and duration of 120 fs is launched into the 5 mm long waveguide. When the pulse train including 50 pulses at a repetition rate of 100 MHz is used as the pump source, the SC-based frequency comb is obtained.

This study examined the toxicities of Fe/Ni and starch-stabilized Fe/Ni (S-Fe/Ni) nanoparticles (NPs) toward Escherichia coli. The inactivation of E. coli by Fe/Ni NPs was concentration- and time-dependent. Fe/Ni NPs exhibited a stronger toxicity than the bare Fe0 NPs (i.e., Ni = 0 wt%), revealing that the loading of Ni increased the toxicity of Fe0 NPs. However, there was no positive correlation between Ni content and the toxicity of Fe/Ni NPs when Ni content increased from 1 wt% to 5 wt%. The starch coating could alleviate the toxicity of Fe/Ni NPs, depending on starch concentration. Transmission Electron Microscopy analysis demonstrates that membrane disruption and cellular internalization of NPs occurred for E. coli after exposure to the Fe/Ni NPs. The NPs might have reacted with the carboxyl, ester and amine groups on the cell surface, as indicated by the Fourier Transform Infrared Spectroscopy analysis. However, the S-Fe/Ni NPs did not cause obvious membrane disruption of the cells due to the effect of starch coating, which inhibited the close contact of NPs with cells by providing electrostatic repulsion and steric hindrance. Besides, the addition of N-Acetyl-L-cysteine, as a potent scavenger for reactive oxygen species (ROS), remarkably reduced the toxicities of both Fe/Ni and S-Fe/Ni NPs, which indicated that the ROS-induced oxidative stress should be the primary mechanism for the inactivation of E. coli. The aging experiments evidenced that both Fe/Ni and S-Fe/Ni NPs would lose their toxic potential over time, posing less threat to the environment in the long term.

It is generally accepted that glucose oxidase (GOx) shows unique specificity in β-d-glucose catalysis. However, it has been found that GOx can catalyze diverse monosaccharides. Therefore, the sensing accuracy for glucose biosensors using GOx as probes will be largely compromised by the presence of other monosaccharides. Herein, multifunctional bi-nanospheres (Fe

In this work, biochar-supported nanoscale zero-valent iron (nZVI/BC) was synthesized and used as an activator for Fenton-like removal of sulfamethazine (SMT). The possible removal mechanisms in the reaction system were proposed. nZVI was mainly responsible for H2O2 decomposing to generate OH for the degradation of SMT, while BC played multiple roles, i.e., preventing nZVI aggregation, adsorbing SMT, activating H2O2, and alleviating nZVI passivation. The effects of various factors (i.e., the mass ratio of nZVI to BC, solution pH, H2O2 concentration and nZVI/BC dosage) on SMT removal were evaluated. The highest removal efficiency (74.04%) of SMT (10 mg/L) was achieved at the optimal conditions (the mass ratio of nZVI and BC = 1:5, pH = 3, H2O2 = 20 mM and nZVI/BC = 1.2 g/L). Additionally, the feasibility of recycling of nZVI/BC composites was examined. It was found that the removal efficiency of SMT decreased significantly from 74.04% to 53.28% and 38.02%, respectively, in the second and third run of experiments. X-ray diffraction analysis of the recycled composites demonstrated the gradual loss of Fe0 content after each run of experiment, which resulted in the decrease of catalytic activity of nZVI/BC composites and thus the drop of SMT removal.