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The rational design of a semiconductor heterostructure plays a crucial role in achieving high-performance photoelectrochemical (PEC) applications, such as photodetectors and water splitting due to the diverse functions of the heterointerface in light absorption, corrosion protection, and carrier transportation. Herein, we propose an approach by fully attaching Bi2S3 nanoparticles onto Bi2MoO6 nanorods to fabricate a photoanode for efficient self-powered PEC photodetection and water splitting. This photoanode exhibits remarkable responsivity (11.50 mA/W), rapid response time (200 μs), excellent photon-to-electron conversion efficiency (32.02%), and long-term stability (30,000 s) even without an external bias voltage. These enhancements can be attributed to effective charge separation, unique nanostructural morphology, and an enhanced light capture ability. Leveraging these advantages, the Bi2S3/Bi2MoO6 heterostructure demonstrates an exceptionally high, stable, and bias-free PEC hydrogen evolution rate of 418.95 μmol/cm2/h, surpassing that of both pure Bi2S3 and Bi2MoO6 by factors of 249.38 and 55.38, respectively. Furthermore, compared to previously reported Bi2MoO6-related heterostructures, the Bi2S3/Bi2MoO6 heterostructure exhibits superior PEC catalytic performance. [ABSTRACT FROM AUTHOR]

In recent years, potential health hazards associated with tritium radiation have received increased attention. The medical emergency response to tritium-related accidents requires highly specialized and technical expertise with broad coverage and significant impact. In China, nuclear- and radiation-related laws and regulations have a complete emergency system and rescue management plan for dealing with such emergencies. These provisions, combined with the specific characteristics of tritium radiation accidents, underscore the need for the implementation of a medical emergency response. This Account presents guiding opinions for the medical emergency response and management of tritium-related accidents by introducing a three-level rescue system and analyzing medical rescue and psychological assistance for people exposed to tritium in such accidents. [ABSTRACT FROM AUTHOR]

The article presents a study that focuses on a strategy for constructing near-infrared (NIR) light emitting luciferase through biomineralization processes. It states that the method is the first enzyme-templated synthesis of NIR quantum dots (QDs). The study found out that the luciferase remains active and enables bioluminescence resonance energy transfer (BRET) in the Luc8-Pbs complex, indicating an advance on previous templated nanomaterial synthesis.

Smart fibers capable of integrating the multifunctionality of actuation and self-sensation into a single proprioceptive device have significant applications in soft robots and biomedicine. Especially, the achievement of self-sensing the movement patterns of different actuating segments in one fiber is still a great challenge. Herein, in this study, a fiber with the controllable Janus architecture is successfully proposed via an artful centrifugation-driven hierarchical gradient self-assembly strategy, which couples two functional components of piezoresistive carbon nanotubes and magnetic NdFeB nanoparticles into the upper and lower layers of this flexible fibrous framework with the porous sponge structure partially, respectively. As predicted, the final product exhibits the as-anticipated bionic proprioceptive behaviors of programmable actuating deformation and highly selective response to bending, stretching, and pressure with high washable stability and mechanical performances. More importantly, assisted by the different three-dimensional printing molds, the superlong Janus fibers with various controllable lengths of the reversed but sequential multistage segments can be fabricated, offering the hybrid magnetic actuation and proprioceptive sensation existing at arbitrary nodes. Therefore, several kinds of soft organism-inspired Janus fiber-derived soft robots with the arbitrarily controlled segmental characters were assembled as the proof-of-concept, which can not only realize a snake or inchworm-inspired successive contracting-stretching deformation and a sperm-inspired self-rotating crawling motion but also self-sense the signals of each segment themselves in real time and then be used to navigate an object to target position in a liquid-filled confined tube. It is believed that this work promotes the further development of proprioceptive soft robots.

Supramolecular delivery systems with the prolonged circulation, the potential for diverse functionalization, and few toxin-related limitations have been extensively studied. For the present study, we constructed a linear polyglycerol-shelled polymersome attached with the anti-HER-2-antibody trastuzumab. We then covalently loaded the anticancer drug DM1 in the polymersome via dynamic disulfide bonding. The resulted trastuzumab-polymersome-DM1 (Tra-PS-DM1) exhibits a mean size of 95.3 nm and remarkable drug loading efficiency % of 99.3%. In addition to its superior stability, we observed the rapid release of DM1 in a controlled manner under reductive conditions. Compared to the native polymersomes, Tra-PS-DM1 has shown greatly improved cellular uptake and significantly reduced IC 50 up to 17-fold among HER-2-positive cancer cells. Moreover, Tra-PS-DM1 demonstrated superb growth inhibition of HER-2-positive tumoroids; specifically, BT474 tumoroids shrunk up to 62% after 12 h treatment. With exceptional stability and targetability, the PG-shelled Tra-PS-DM1 appears as an attractive approach for HER-2-positive tumor treatment.

Nitrogen dioxide (NO 2 ) hydrolysis in deliquesced aerosol particles forms nitrous acid and nitrate and thus impacts air quality, climate, and the nitrogen cycle. Traditionally, it is considered to proceed far too slowly in the atmosphere. However, the significance of this process is highly uncertain because kinetic studies have only been made in dilute aqueous solutions but not under high ionic strength conditions of the aerosol particles. Here, we use laboratory experiments, air quality models, and field measurements to examine the effect of the ionic strength on the reaction kinetics of NO 2 hydrolysis. We find that high ionic strengths ( I ) enhance the reaction rate constants ( k I ) by more than an order of magnitude compared to that at infinite dilution ( k I =0 ), yielding log 10 ( k I / k I =0 ) = 0.04 I or rate enhancement factor = 10 0.04 I . A state-of-the-art air quality model shows that the enhanced NO 2 hydrolysis reduces the negative bias in the simulated concentrations of nitrous acid by 28% on average when compared to field observations over the North China Plain. Rapid NO 2 hydrolysis also enhances the levels of nitrous acid in other polluted regions such as North India and further promotes atmospheric oxidation capacity. This study highlights the need to evaluate various reaction kinetics of atmospheric aerosols with high ionic strengths.

Two new mixed-anion cerium iodates, namely, Ce(IO 3 ) 3 F and Ce(IO 3 ) 2 (NO 3 ), have been rationally designed through the integration of hybrid anionic functional building blocks (FBBs). The structure of Ce(IO 3 ) 3 F features a novel [Ce(IO 3 ) 3 F] bilayer, and the material exhibits large birefringence (0.225 @546 nm). The structure of Ce(IO 3 ) 2 (NO 3 ) features [Ce 3 (IO 3 ) 6 ] 3+ triple layers that are further linked by planar NO 3 - units. Ce(IO 3 ) 2 (NO 3 ) shows a moderate SHG response (1 × KDP) and a high laser-induced damage threshold value (22 × AgGaS 2 ). This work demonstrates that the rich coordination geometries of cerium cations facilitate tuning of the structures of related compounds through modulating anionic FBBs.

Cobalt-mediated radical polymerization is noted for its great level of control over the polymerization of acrylic and vinyl esters monomers, even at high molar mass. Vitamin B 12 , a natural bionic enzyme cobalt complex, involves the conversion of organic halides to olefins through chain-growth polymerization. In this work, the notion of R-Co(III) free radical persistent free radical effect and vitamin B 12 circulation were first reported for the perception of ultralow abundance of microRNA-21, a lung cancer biomarker. Indeed, most Co-containing catalytic reactions can occur under mild conditions due to their minimal bond dissociation of the C-Co bond, with blue light irradiation. Based on the intrinsic stability of the vitamin B 12 framework and recycling of the catalyst, it is evident that this natural catalytic scheme has potential applications in medicinal chemistry and biomaterials. In addition, this strategy, combined with highly specific recognition probes and vitamin B 12 circulation-mediated chain-growth polymerization, has a detection limit as low as 910 aM. Furthermore, it is sensitive for sensing in serum samples containing biomarkers and shows great potential for RNA selection and amplification sensing in clinical samples.

Ferroelectric materials bring new opportunities for self-powdered photodetectors, taking advantage of their anomalous bulk photovoltaic effect. However, ferroelectric-based photodetectors suffer from relatively poor responsivity and detectivity due to obstacles of low electrical conductivity and low photoelectric conversion ability. The present work proposes a strategy based on heterovalent ion Ce-doping into BaTiO 3 (Ce-BTO) that gives rise to a good room temperature conductivity combined with a significant PTCR (positive temperature coefficient of resistivity) effect. By utilizing a Ce-BTO PTCR semiconductor, a high-performance self-powered photodetector ITO/Ce-BTO/Ag is fabricated, demonstrating a polarity-switchable photoresponse with the change of wavelength due to the competition between hot electrons induced by the Ag plasmonic effect and electron-hole pairs separated by a Schottky barrier. Moreover, benefiting from the reduced bandgap and the introduced impurity states, good responsivity (9.85 × 10 -5 A/W) and detectivity (1.25 × 10 10 Jones) as well as fast response/recovery time (83/47 ms) is achieved under 450 nm illumination. Finally, four representative logic gates ("OR", "AND", "NOR", and "NAND") are demonstrated with one photodetector via the bipolar photoresponse. This work opens an avenue to promote the application of PTCR semiconductors in optoelectronics, offering a conceivable means toward high-performance self-powered photodetectors.

To mimic the natural photosynthesis system, a Z-scheme heterostructure is proposed as a viable and effective strategy for efficient solar energy utilization such as photocatalysis and photoelectrochemical (PEC) water splitting due to the high carrier separation efficiency, fast charge transport, strong redox, and wide light absorption. However, it remains a huge challenge to form a direct Z-scheme heterostructure due to the internal electric-field restriction and vital band-alignment at the interface. Herein, the van der Waals heterostructure based on the allotrope SnSe 2 and SnSe is designed and synthesized by a two-step vapor phase deposition method to overcome the limitation in the formation of the Z-scheme heterostructure for the first time. The Z-scheme heterostructure of SnSe 2 /SnSe is confirmed by X-ray photoelectron spectroscopy, ultraviolet photoelectron spectroscopy, PEC measurement, density functional theory calculations, and water splitting. Strikingly, the PEC photodetectors based on the Z-scheme heterostructure show a synergistic effect of superior stability from SnSe and fast photoresponse from SnSe 2 . As such, the SnSe 2 /SnSe Z-scheme heterostructure shows a good photodetection performance in the ultraviolet to visible wavelength range. Furthermore, the photodetector shows a faster response/recovery time of 13/14 ms, a higher photosensitivity of 529.13 μA/W, and a higher detectivity of 4.94 × 10 9 Jones at 475 nm compared with those of single components. Furthermore, the photodetection stability of the SnSe 2 /SnSe is also greatly improved by a-thin-Al 2 O 3 -layer passivation. The results imply the promising rational design of a direct Z-scheme heterostructure with efficient charge transfer for high performance of optoelectronic devices.

Accurate determination of acidity (pH) and ion activities in aqueous droplets is a major experimental and theoretical challenge for understanding and simulating atmospheric multiphase chemistry. Here, we develop a ratiometric Raman spectroscopy method to measure the equilibrium concentration of sulfate (SO 4 2- ) and bisulfate (HSO 4 - ) in single microdroplets levitated by aerosol optical tweezers. This approach enables determination of ion activities and pH in aqueous sodium bisulfate droplets under highly supersaturated conditions. The experimental results were compared against aerosol thermodynamic model calculations in terms of simulating aerosol ion concentrations, ion activity coefficients, and pH. We found that the Extended Aerosol Inorganics Model (E-AIM) can well reproduce the experimental results. The alternative model ISORROPIA, however, exhibits substantial deviations in SO 4 2- and HSO 4 - concentrations and up to a full unit of aerosol pH under acidic conditions, mainly due to discrepancies in simulating ion activity coefficients of SO 4 2- -HSO 4 - equilibrium. Globally, this may cause an average deviation of ISORROPIA from E-AIM by 25 and 65% in predicting SO 4 2- and HSO 4 - concentrations, respectively. Our results show that it is important to determine aerosol pH and ion activities in the investigation of sulfate formation and related aqueous phase chemistry.

Bright red-emitting phosphors with high color purity and high photoluminescence quantum yield (PLQY) are highly demanded for the fabrication of high-performance warm-white light-emitting diodes (LEDs). Herein, we demonstrated a novel efficient Eu 3+ -activated Ca 2 LaHf 2 Al 3 O 12 garnet phosphor with excellent luminescence properties for near-ultraviolet (near-UV) excited warm-white LEDs. The Ca 2 LaHf 2 Al 3 O 12 :Eu 3+ phosphors exhibited an intense excitation spectrum in the near-UV region with a maximum around 394 nm, and they produced dazzling red luminescence peaking at 592, 614, 659, and 711 nm due to the 5 D 0 → 7 F J ( J = 1-4) transitions of Eu 3+ ions when the excitation wavelength was set at 394 nm. Luminescent properties have been studied as a function of Eu 3+ doping concentration, and the highest emission intensity was achieved at 50 mol % Eu 3+ , while the dipole-dipole interaction brought the concentration quenching effect. The Ca 2 LaHf 2 Al 3 O 12 :50%Eu 3+ sample exhibited CIE chromaticity coordinates of (0.6419, 0.3575) with a color purity of 92.7%, and its PLQY was measured to be 64%. The thermal stability and activation energy of Ca 2 LaHf 2 Al 3 O 12 :50%Eu 3+ phosphors were also discussed and analyzed. Finally, we made a near-UV chip-based white LED device in which the Ca 2 LaHf 2 Al 3 O 12 :50%Eu 3+ phosphor was utilized as a red ingredient. A bright warm-white light emission was realized from this LED device under 80 mA driving current, accompanied by a high color rendering index (CRI) of 88.3, a low correlation color temperature of 3853 K, and good CIE chromaticity coordinates of (0.3909, 0.3934). These results revealed that these red-emitting Ca 2 LaHf 2 Al 3 O 12 :Eu 3+ phosphors have promising application prospect in near-UV-excited warm-white LEDs with high a CRI.

Phosphor-containing white light-emitting diodes (LEDs) with low color-correlated temperatures (CCTs) and high color rendering indexes (CRIs) are highly desirable for energy-efficient and environmentally friendly solid-state light sources. Here, we report a new and efficient blue light-excited, green-emitting Ce 3+ -activated CaY 2 ZrScAl 3 O 12 phosphor, which underpins the fabrication of high-color quality and full-visible-spectrum warm-white LED devices with ultrahigh CRI values (Ra > 96 and R9 > 96). A family of CaY 2 ZrScAl 3 O 12 :Ce 3+ phosphors with different Ce 3+ dopant concentrations were prepared by high-temperature solid-state synthesis. X-ray diffraction and corresponding Rietveld refinement reveal a garnet structure with an Ia 3̅ d space group and crystallographic parameters a = b = c = 12.39645(8) Å, α = β = γ = 90°, and V = 1904.99(4) Å 3 . Luminescence properties were studied in detail as a function of Ce 3+ with the optimal concentration 1% mol. Impressively, CaY 2 ZrScAl 3 O 12 :1%Ce 3+ exhibits a broad excitation band from 370 to 500 nm, peaking at ∼421 nm, which is well matched with emission from commercial blue LED chips. Under 421 nm excitation, the CaY 2 ZrScAl 3 O 12 :1%Ce 3+ phosphor produces dazzling green light in a wide emission band from 435 to 750 nm (emission peak: 514 nm; full width at half-maximum: 113 nm), with a high internal quantum efficiency of 63.1% and good resistance to thermal quenching (activation energy of 0.28 eV). A white LED device combining a 450 nm blue LED chip with CaY 2 ZrScAl 3 O 12 :1%Ce 3+ green phosphor and commercial CaAlSiN 3 :Eu 2+ red phosphor as color converters demonstrates bright warm-white light with excellent CIE color coordinates of (0.3938, 0.3819), low CCT of 3696 K, high CRI (Ra = 96.9, R9 = 98.2), and high luminous efficacy of 45.04 lm W -1 under a 20 mA driving current. New green phosphors enable the design and implementation of efficient luminescent materials for healthy solid-state lighting.

Bacterial infection and blockage are severe problems for polyurethane (PU) catheters and there is an urgent demand for surface-functionalized polyurethane. Herein, a cationic alternating copolymer comprising allyl-substituted ornithine and glycine (allyl-substituted poly(Orn-alter-Gly)) with abundant carbon-carbon double bond functional groups (C═C) is designed. Polyurethane is prepared with a large quantity of C═C groups (PU-D), and different amounts of allyl-substituted poly(Orn-alter-Gly) are grafted onto the PU-D surface (PU-D-2%AMPs and PU-D-20%AMPs) via the C═C functional groups. The chemical structures of the allyl-substituted poly(Orn-alter-Gly) and polyurethane samples (PU, PU-D, PU-D-2%AMPs, and PU-D-20%AMPs) are characterized and the results reveal that allyl-substituted poly(Orn-alter-Gly) is decorated on the polyurethane. PU-D-20%AMPs shows excellent antibacterial activity against Escherichia coli, Enterococcus faecalis , and Staphylococcus aureus because of the high surface potential caused by cationic allyl-substituted poly(Orn-alter-Gly), and it also exhibits excellent long-term antibacterial activity and antibiofilm properties. PU-D-20%AMPs also has excellent antifouling properties because the cationic copolymer is fixed at multiple reactive sites, thus avoiding the formation of movable long chain brush. A strong surface hydration barrier is also formed to prevent adsorption of proteins and ions, and in vivo experiments reveal excellent biocompatibility. This flexible strategy to prepare dual-functional polyurethane surfaces with antibacterial and antifouling properties has large potential in biomedical implants.

Combination therapy via stimulus-responsive drug release is known to improve treatment efficacy and minimize side effects. However, the use of low-abundance cancer biomarkers as molecular triggers to induce efficient drug release for combination therapy still remains a challenge. Herein, we developed a dual microRNA-responsive drug nanocarrier for catalytic release of doxorubicin (Dox) and small interfering RNA (siRNA) in cancerous cells for combined chemotherapy and gene therapy with logic operation. The nanocarrier is constructed by assembling two duplexes of DNA/RNA and Dox molecules onto DNA-functionalized gold nanoparticles. Two microRNA molecules (miRNA-21 and miRNA-10b overexpressed in MDA-MB-231) could alternatively catalyze the disassembly of the nanocarrier through a thermodynamically driven entropy gain process, during which Dox molecules are released, and the two pairs of released DNA/RNA duplex hybridize to generate siRNA (siBcl-2) in situ by strand displacement reactions. Quantum dots are used to track the process in living cells. The AND logic gate-based drug release system allows effective treatment of specific cancer cell types according to miRNA expression patterns. This strategy represents an effective means to overcome multidrug resistance and improve therapeutic effects.

The oxidation of nitric oxide to nitrogen dioxide by hydroperoxy (HO 2 ) and organic peroxy radicals (RO 2 ) is responsible for the chemical net ozone production in the troposphere and for the regeneration of hydroxyl radicals, the most important oxidant in the atmosphere. In Summer 2014, a field campaign was conducted in the North China Plain, where increasingly severe ozone pollution has been experienced in the last years. Chemical conditions in the campaign were representative for this area. Radical and trace gas concentrations were measured, allowing for calculating the turnover rates of gas-phase radical reactions. Therefore, the importance of heterogeneous HO 2 uptake on aerosol could be experimentally determined. HO 2 uptake could have suppressed ozone formation at that time because of the competition with gas-phase reactions that produce ozone. The successful reduction of the aerosol load in the North China Plain in the last years could have led to a significant decrease of HO 2 loss on particles, so that ozone-forming reactions could have gained importance in the last years. However, the analysis of the measured radical budget in this campaign shows that HO 2 aerosol uptake did not impact radical chemistry for chemical conditions in 2014. Therefore, reduced HO 2 uptake on aerosol since then is likely not the reason for the increasing number of ozone pollution events in the North China Plain, contradicting conclusions made from model calculations reported in the literature.

Nowadays, monitoring and recording CO 2 gas has become more and more important in various areas, leading to increasing demand for developing high-sensitive CO 2 sensors. In this study, a novel potentiometric CO 2 gas sensor is designed based on a new solid electrolyte of Y-doped La 9.66 Si 5.3 B 0.7 O 26.14 (Y-LSBO), coated with the Li 2 CeO 3 -Au-Li 2 CO 3 composite as a sensing electrode and Pt as a reference electrode. With the optimized composition of a sensing electrode, the electromotive force (EMF) varies linearly with the logarithm of the CO 2 concentration in the range of 400-4000 ppm, exhibiting an excellent Nernstian response to CO 2 gas in both dry and humid atmospheres. The fabricated CO 2 sensor can be well operated at 400 °C in a dry atmosphere and 450 °C in a humid atmosphere. Based on the results, we have proposed that the good CO 2 sensing performance may be associated with Li 2 CeO 3 playing a role of "ionic bridge" between the O 2- conductor (Y-LSBO) and the Li + conductor (Li 2 CO 3 ). This study not only shows the promising potential of a Y-LSBO solid electrolyte utilized in the field of gas sensors but also enriches the research of solid electrolyte-based potentiometric CO 2 gas sensors.