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Maximizing the molecular information density requires simultaneously functionalizing distinct monomers and their coupling connections. However, current synthesis generally focuses on distinct monomers rather than coupling reactions because the multistep reactions significantly escalate the synthetic complexity in an exponential increase. Here, we report the two-dimensional nanoarchitectures (2DNs) of end-on oligomers, with versatile molecular structures and negative differential resistance (NDR), synthesized by programmed and surface-initiated step electrosynthesis based on the simultaneous utilization of six reactions including cross- and homocouplings. The resulting vertically end-on oligomers, with similar values in thickness and molecular length, as crystalline 2DNs, exhibit subnanometer uniformity, ultrahigh compressive modulus of 40 GPa, and low-bias NDR at 0.13 V with an ultralow power consumption of down to 0.05 nW/μm2. This highly controlled electrosynthesis provides a unique dimension to enhance the structural diversity of molecular 2D nanomaterials for high-density and low-power consumption electronics.

Self-powered photodetectors (PD) based on ferroelectric materials have gained huge attention because of the spontaneous polarization and unique photovoltaic effect. However, the low photocurrent values and switch ratio of the ferroelectric materials limit their further practical applications in a wide temperature range. In this study, the self-powered ZnO nanofiber array/BaTiO3(ZnO-NFA/BTO) PD was fabricated by high-ordered ZnO-NFA via electrospinning method deposited on a 300 nm BTO film synthesized using sol–gel method. The electrospinning can prepare ZnO-NFAs with a controllable diameter (100 nm) and orientation and is directly deposited on the quartz at a large scale, which simplifies the fabrication process. This device possesses a greater on/off ratio of 2357 at zero bias than that of BTO PD (3.33) and the ZnO-NFA PD (125) at 0.2 V. The highest responsivity and specific detectivity are 1.41 mA W–1and 1.48 × 109Jones at 368 nm under 0 V bias, respectively, which is enhanced about three magnitudes than the pristine BTO PD (1.21 μA W–1and 1.02 × 109Jones). The photocurrent of the ZnO-NFA/BTO PD strongly depends on the temperature. After the cooling system and prepolarization processing are both introduced, the largest light current (475 nA) and photovoltaic plateaus (585 nA) are enhanced by about 4417 and 4278% under 368 nm at a power intensity of 4.46 mW cm–2at 0 °C, respectively. The enhancement of photocurrent is associated with a ferro-pyro-phototronic effect, evidenced by enhanced ferroelectric polarization. The ZnO-NFA/BTO PD can detect weak signals at low power intensity with a wide temperature range of 0–100 °C under 0 V bias. The self-powered ZnO-NFA/BTO PD provides a new and promising way to fabricate high-performance and low-cost photodetectors from inorganic perovskite materials.

Cost-efficient and durable manganese-based catalysts are in great demand for the catalytic elimination of volatile organic compounds (VOCs), which are dominated not only by the nanostructures but also by the oxygen vacancies and Mn–O bond in the catalysts. Herein, a series of nanostructured Co–Fe-doped-δ-MnO2catalysts (Co–Fe-δ-MnO2) with high dispersion were in situfabricated by employing metal–organic-frameworks (MOFs) as reducing agents, dopants, and templates all at the same time. The as-obtained Co–Fe-δ-MnO2-20% catalyst exhibited robust durability and high catalytic activity (225 °C) for toluene combustion even in the presence of 5 vol % water vapor, which is 50 °C lower than that of pristine δ-MnO2. Various characterizations revealed that the homogeneously dispersed codoping of Co and Fe ions into δ-MnO2promotes the generation of oxygen vacancies and weakens the strength of the Mn–O bond, thus increasing the amount of adsorbed oxygen (Oads) and improving the mobility of lattice oxygen (Olatt). Meanwhile, due to successfully inheriting the framework structures of MOFs, the obtained catalyst exhibited a high surface area and three-dimensional mesoporous structure, which contributes to diffusion and increases the number of active sites. Moreover, in situDRIFTS results confirmed that the toluene degradation mechanism on the Co–Fe-δ-MnO2-20% follows the MVK mechanism and revealed that more Oadsand high-mobility Olattinduced by this novel method contribute to accumulating and mineralizing key intermediates (benzoate) and thus promote toluene oxidation. In conclusion, this work stimulates the opportunities to develop Co–Fe-δ-MnO2as a class of nonprecious-metal-based catalysts for controlling VOC emissions.

The key to saving lives is to achieve instant and effective sealing hemostasis in the event of emergency bleeding. Herein, a plant oil-based EMTA/Zn2+bioadhesive is prepared by a facile reaction of epoxidized soybean oil (ESO) with methacrylic acid (MAA) and tannic acid (TA), followed by the addition of zinc ions for coordination with TA. The EMTA/Zn2+bioadhesive can be rapidly cured in situat the wound site through photo-cross-linking under ultraviolet (UV) light-emitting diode (LED) irradiation within 30 s, achieving ultrastrong wet-tissue adhesion performance of 92.4 and 51.8 kPa to porcine skin and aortic skin after 7 days underwater, respectively. Especially, the EMTA/Zn2+bioadhesive exhibits outstanding sealing performance in vitrowith the high burst pressure of 525 mmHg (70 kPa) and 337.5 mmHg (45 kPa) to porcine skin and aortic skin, respectively. Moreover, the EMTA/Zn2+bioadhesive not only has outstanding hemocompatibility and good biodegradability but also exhibits excellent cytocompatibility and antibacterial properties. Notably, the EMTA/Zn2+bioadhesive has remarkable instant sealing hemostatic ability for hemorrhaging liver in vivo. Therefore, the prepared plant oil-based EMTA/Zn2+bioadhesive can serve as a charming alternative candidate for instant sealing hemostasis in clinical applications, especially in traumatic internal organs and arterial bleeding.

It is important to explore and develop multifunctional phase change composites with high latent-heat capacity and photothermal conversion capability. A novel ultralight and flexible carbon foam (CF)-based phase change composite was fabricated by encapsulating n-eicosane into a CF skeleton that had been precoated with titanium(III) oxide (Ti2O3) nanoparticles (NPs). Morphological structures, as well as the properties of leakage-proof, thermal energy storage, temperature regulation, and photothermal conversion, of the fabricated phase change composites were investigated. The results indicated that the flexible CF skeleton derived from melamine foam (MF) through stabilization in air followed by carbonization in nitrogen was highly porous, which ensured excellent mechanical support and large mass ratio of n-eicosane for the composites. The loading percentage of n-eicosane as high as 84% which acted as thermal storage unit guaranteed high latent-heat capacity and good temperature regulation property of the composite; the melting/crystallization temperatures and enthalpies of the corresponding composite was 36.4/33.7 °C and 200.1/200.6 kJ·kg–1, respectively. The CF skeleton modified with Ti2O3NPs endowed the fabricated phase change composites with enhanced leakage-proof property, photothermal conversion capability, superior thermal reliability, and temperature regulation ability. Therefore, the resultant phase change composites are believed to have promising and potential applications in solar thermal-energy storage, waste-heat recovery, and infrared stealth of military targets, and so forth.

Magnetic/antibacterial bifunctional nanoparticles were fabricated through the immobilization of antibacterial N-halamine on silica-coated Fe3O4-decorated poly(styrene-co-acrylate acid) (PSA) nanoparticles. The samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectra (XPS), X-ray diffraction (XRD), energy-dispersive X-ray spectrometry (EDX), Fourier transform infrared (FTIR), and thermogravimetric analysis (TGA). The N-halamine was developed from the precursor 5,5-dimethylhydantoin (DMH) by chlorination treatment, and experimental results showed that the loading amount of DMH on the silica-coated Fe3O4-decorated poly(styrene-co-acrylate acid) nanoparticles was adjustable. The as-synthesized nanoparticles exhibited superparamagnetic behavior and had a saturation magnetization of 18.93 emu g–1. Antibacterial tests showed that the resultant nanoparticles displayed enhanced antibacterial activity against both Gram-positive and Gram-negative bacteria compared with their bulk counterparts.