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Breast cancer is the most common cancer among women, with over 1 million new cases and around 400,000 deaths annually worldwide. This makes it a significant and costly global health challenge. Standard treatments like chemotherapy and radiotherapy, often used after mastectomy, show varying effectiveness based on the cancer subtype. Combining these treatments can improve outcomes, though radiotherapy faces limitations such as radiation resistance and low selectivity for malignant cells. Nanotechnologies, especially metallic nanoparticles (NPs), hold promise for enhancing radiotherapy. Gold nanoparticles (AuNPs) are particularly notable due to their high atomic number, which enhances radiation damage through the photoelectric effect. Studies shown that AuNPs can act as effective radiosensitizers, improving tumor damage during radiotherapy increasing the local radiation dose delivered. Traditional AuNPs synthesis methods involve harmful chemicals and extreme conditions, posing health risks. Green synthesis methods using plant extracts offer a safer and more environmentally friendly alternative. This study investigates the synthesis of AuNPs using Laurus nobilis leaf extract and their potential as radiosensitizers in breast carcinoma cell lines (MCF-7). These cells were exposed to varying doses of X-ray irradiation, and the study assessed cell viability, morphological changes and DNA damage. The results showed that green-synthesized AuNPs significantly enhanced the therapeutic effects of radiotherapy at lower radiation doses, indicating their potential as a valuable addition to breast cancer treatment. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Using ab initio calculations, the structural and photoelectric properties of γ-GeSe with B, C, and N adsorption were systematically investigated. The atomic structure relaxations show that B, C, and N are preferentially located on the lower hexagonal hollow, upper hexagonal hollow, and on top of Se, respectively. The adsorption with B, C, and N can induce defective bands between the energy region n of the valence bands and the conduction bands, and all the systems with adatoms are magnetic, with 1 μB, 2 μB, and 1 μB magnetic moments, respectively, which are mainly caused by the hybridization between adatoms and the adjacent Ge and Se atoms. Based on the spin-polarized band structure, we find that C-adsorbed γ-GeSe is metallic, while γ-GeSe with B and N adatoms is half-metallic, with 100% spin polarization at the Fermi level. Furthermore, owing to the electronic structural differences between spin-up and spin-down sections of B- and N-adsorbed γ-GeSe, the light in the low-energy region (< 1.0 eV) can only cause electronic excitations in one spin channel, giving rise to interesting spin-polarized photoelectric properties. Our results suggest that γ-GeSe with B, C, and N adsorption is a promising candidate for spintronic photoelectric device applications. [ABSTRACT FROM AUTHOR]

Nanoparticle radioenhancement offers a promising strategy for augmenting radiotherapy by locally increasing radiation damage to tumor tissue. While past research has predominantly focused on nanomaterials with high atomic numbers, such as Au and HfO2, recent work has revealed that their radioenhancement efficacy decreases considerably when using clinically relevant megavoltage X‐rays as opposed to the orthovoltage X‐rays typically employed in research settings. Here, radiocatalytically active Ti‐based nanomaterials for clinical X‐ray therapy settings are designed. A range of candidate materials, including TiO2 (optionally decorated with Ag or Pt nanoseeds), Ti‐containing metal–organic frameworks (MOFs), and 2D Ti‐based carbides known as Ti3C2Tx MXenes, is investigated. It is demonstrated that these titanium‐based candidates remain consistently performant across a wide energy spectrum, from orthovoltage to megavoltage. This sustained performance is attributed to the catalytic generation of reactive oxygen species, moving beyond the simple physical dose enhancements associated with photoelectric effects. Beyond titania, emergent materials like titanium‐based MOFs and MXenes exhibit encouraging results, achieving dose‐enhancement factors of up to three in human soft tissue sarcoma cells. Notably, these enhancements are absent in healthy human fibroblast cells under similar conditions of particle uptake, underscoring the selective impact of titanium‐based materials in augmenting radiotherapy across the clinically relevant spectral range. [ABSTRACT FROM AUTHOR]

Untethered electrical stimulation or pacing of the heart is of critical importance in addressing the pressing needs of cardiovascular diseases in both clinical therapies and fundamental studies. Among various stimulation methods, light illumination-induced electrical stimulation via photoelectric effect without any genetic modifications to beating cells/tissues or whole heart has profound benefits. However, a critical bottleneck lies in the lack of a suitable material with tissue-like mechanical softness and deformability and sufficient optoelectronic performances toward effective stimulation. Here, we introduce an ultrathin (<500 nm), stretchy, and self-adhesive rubbery bio-optoelectronic stimulator (RBOES) in a bilayer construct of a rubbery semiconducting nanofilm and a transparent, stretchable gold nanomesh conductor. The RBOES could maintain its optoelectronic performance when it was stretched by 20%. The RBOES was validated to effectively accelerate the beating of the human induced pluripotent stem cell-derived cardiomyocytes. Furthermore, acceleration of ex vivo perfused rat hearts by optoelectronic stimulation with the self-adhered RBOES was achieved with repetitive pulsed light illumination. [ABSTRACT FROM AUTHOR]

Solar rechargeable batteries (SRBs), as an emerging technology for harnessing solar energy, integrate the advantages of photochemical devices and redox batteries to synergistically couple dual‐functional materials capable of both light harvesting and redox activity. This enables direct solar‐to‐electrochemical energy storage within a single system. However, the mismatch in energy levels between coupled photochemical storage materials (PSMs) and the occurrence of side reactions with liquid electrolytes during charge‐discharge cycles lead to a decrease in solar energy conversion efficiency. This impedes the advancement of SRBs. This review comprehensively discusses of the latest advancements in PSMs, which are crucial for designing advanced SRBs. It delves into an extensive discussion of the design criteria for dual‐functional photochemical storage cathodes (PSCs) and elucidates the operational mechanism of SRBs. Additionally, it further discusses the performance, efficiency, and long‐term cycle stability of SRBs in relation to photoelectronic and photothermal mechanisms. Finally, an outlook on primary challenges and prospects that SRBs will encounter is provided to offer novel insights for their technological advancement. [ABSTRACT FROM AUTHOR]

The ion drag pump, as one kind of electrohydrodynamic pump, has received considerable attention in fluid applications due to its excellent pumping flow rate and pressure. However, there is a lack of systematic research about the factors that influence pumping performance of the ion drag pump. Here, a photo-induced ion drag pump based on the PLZT ceramic is proposed by combining the photoelectric effect and field emission phenomenon. The EHD model of this ion drag pump is constructed based on the mathematical model of the photovoltage of the PLZT ceramic, through which a series of finite element simulations are carried out to comprehensively investigate the factors that influence the pumping performance. The results demonstrate that such an ion drag pump is able to be improved by optimizing the electrode structure and fluid channel; increasing the light intensity; and providing a basic design guideline for applications of ion drag pumps in microfluidics, soft robots, and heat dissipation in micro devices. [ABSTRACT FROM AUTHOR]

The discovery and measurements of symmetric normal Archimedean spirals from atomic ionization by a pair of time-delayed broadband oppositely circularly polarized pulses revealed their potential of discerning orbital symmetry in atoms. Transferring this tool to molecules substantially increases experimental and theoretical challenges. Here, we show how Einstein's photoelectric effect bypasses the congestion of electronic intermediate states and can access the orbital symmetry in heteronuclear, multi-orbital aligned molecules. Thanks to the broad bandwidth, multi-orbital ionization leads to multiplexed molecular-frame photoelectron momentum distributions, hiding thus any molecular orbital information. Only when molecular orientation is used to manipulate the ionization channels that one can identify a robust doorway into the molecular quantum world in which the asymmetry inherent to the highest-occupied molecular orbital can be unambiguously revealed by the asymmetric molecular spirals from single-color pulses. Our results demonstrate the potential of polarization-tailored attopulse sequences for the retrieval of spectroscopic details on molecular orbital symmetries. For pulse bandwidth larger than the energy gap between molecular orbitals, distinguishing contributions of electrons photoionized from different orbitals is a major hurdle. Here, the authors mitigate this issue by rotating light with respect to the molecular axis and show that asymmetric spirals are a new source of information for molecular orbital symmetries. [ABSTRACT FROM AUTHOR]

The possibility of a quantum system to exhibit properties that are akin to both the classically held notions of being a particle and a wave, is one of the most intriguing aspects of the quantum description of nature. These aspects have been instrumental in understanding paradigmatic natural phenomena as well as to provide non-classical applications. A conceptual foundation for the wave nature of a quantum state has recently been presented, through the notion of quantum coherence. We introduce here a parallel notion for the particle nature of a quantum state of an arbitrary physical system. We provide elements of a resource theory of particleness, and give a quantification of the same. Finally, we provide evidence for a complementarity between the particleness thus introduced, and the coherence of an arbitrary quantum state. [ABSTRACT FROM AUTHOR]

An ionic porous organic polymer nanoparticle coating (TPAPy-IPOP) was constructed by a simple 'one-step' polymerization via an S N2 substitution reaction with a D-A system consisting of TPA and cationized pyridine. The antibacterial coating provides basic protection in the absence of light through cationic antibacterial patterning, and synergizes with photodynamic inactivation to increase antibacterial efficacy under visible light exposure. The antibacterial coating demonstrated favorable biosafety and antibacterial properties in the treatment of wounds infected with drug-resistant bacteria like MRSA. It is expected to constitute the go-to method for the design of antibacterial therapeutic photosensitizers. [Display omitted] Although photodynamic therapy (PDT) has great potential for treating severely infected wounds, it is restricted by the short lifetime, limited diffusion distance of reactive oxygen species (ROS), and incomplete contact with bacteria. Herein, we report a novel nanosized ionic porous organic polymer (TPAPy-IPOP) based on the triphenylamine (TPA) moiety. Strong electron-deficient cationic groups were introduced into TPA to construct the donor–acceptor (D–A) system, in which the photoelectric effect of TPAPy-IPOP was greatly enhanced, and it was easily excited to produce ROS under irradiation with visible light. The introduction of cations not only facilitated bacterial adsorption by TPAPy-IPOP via electrostatic attraction, which was more conducive to killing bacteria by ROS, but also inactivated bacteria by the cations directly. The nanosized TPAPy-IPOP remained suspended in water for several months and could be sprayed onto various substrates to form a durable coating with excellent antibacterial properties. The in vivo results proved that the silk fibroin/polyvinyl alcohol non-woven fabric (SF/PVA) coated with TPAPy-IPOP could create and maintain a sterile microenvironment at a wound site. The rapid reduction in inflammation resulting from its bactericidal action accelerated the wound healing rate. Collectively, this design is expected to offer a generalizable approach for developing novel antibacterial therapeutic photosensitizers, especially for infected wound treatment. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) are robust, porous materials with well‐defined structures that have been employed for gas separation, photoluminescence, sensing, energy storage, and heterogeneous catalysis. This review summarizes recent progress in the use of COFs as a versatile platform for heterogeneous photocatalytic cross‐dehydrogenative coupling (CDC) reactions, which are an efficient and clean methodology for the formation of C−C or C−P bonds. We review the synthesis of these photocatalytic COFs, correlating their catalytic performance with their structures and photoelectric properties. [ABSTRACT FROM AUTHOR]

In this work, the electrical and photoelectric properties of the near-surface and surface layers of silicon doped by diffusion with chromium atoms were investigated. The formation of an anomalous concentration of charge carriers in these regions, as well as an anomalously low mobility, was revealed. The specific conductivity of the near-surface layer with a thickness of 1÷5 μm turned out to be equal to (1.6÷9.9)·10³ Ohm-1·cm-1. The inhomogeneity of the crystal under study was determined by the light probe method. [ABSTRACT FROM AUTHOR]

The single-layer MoS2 is a highly sought-after semiconductor material in the field of photoelectric performance due to its exceptional electron mobility and narrow bandgap. However, its photocatalytic efficiency is hindered by the rapid recombination rate of internal photogenerated electron–hole pairs. Currently, the construction of heterojunctions has been demonstrated to effectively mitigate the recombination rate of photogenerated electron–hole pairs. Therefore, this paper employs the first principles method to calculate and analyze the four heterojunctions formed by MoS2/WSe2, MoS2/MoSe2, MoS2/AlN, and MoS2/ZnO. The study demonstrates that the four heterojunctions exhibit structural stability. The construction of heterojunctions, as compared to a monolayer MoS2, leads to a reduction in the band gap, thereby lowering the electron transition barrier and enhancing the light absorption capacity of the materials. The four systems exhibit II-type heterojunction. Therefore, the construction of heterojunctions can effectively enhance the optical properties of these systems. By forming heterojunctions MoS2/WSe2 and MoS2/MoSe2, the absorption coefficient in the visible light region is significantly increased, resulting in a greater ability to respond to light compared to that of MoS2/ZnO and MoS2/AlN. Consequently, MoS2-based heterojunctions incorporating chalcogenide components WSe2 and MoSe2, respectively, exhibit superior catalytic activity compared to MoS2 heterojunctions incorporating non-chalcogenide components ZnO and AlN, respectively. The absorption spectrum analysis reveals that MoS2/MoSe2 exhibits the highest light responsivity among all investigated systems, indicating its superior photoelectric performance. [ABSTRACT FROM AUTHOR]

Pure tin oxide (SnO2) as a typical conductometric hydrogen sulfide (H2S) gas-sensing material always suffers from limited sensitivity, elevated operation temperature, and poor selectivity. To overcome these hindrances, in this work, hollow CuO-SnO2 nanotubes were successfully electrospun for room-temperature (25 °C) trace H2S detection under blue light activation. Among all SnO2-based candidates, a pure SnO2 sensor showed no signal, even toward 10 ppm, while the 1% CuO-SnO2 sensor achieved a limit of detection (LoD) value of 2.5 ppm, a large response of 4.7, and a short response/recovery time of 21/61 s toward 10 ppm H2S, as well as nice repeatability, long-term stability, and selectivity. This excellent performance could be ascribed to the one-dimensional (1D) hollow nanostructure, abundant p-n heterojunctions, and the photoelectric effect of the CuO-SnO2 nanotubes. The proposed design strategies cater to the demanding requirements of high sensitivity and low power consumption in future application scenarios such as Internet of Things and smart optoelectronic systems. [ABSTRACT FROM AUTHOR]

We investigated the effect of time-dependent ice growth on dust grains on the opacity and hence on the dust temperature in a collapsing molecular cloud core, with the aim of quantifying the effect of the dust temperature variations on ice abundances as well as the evolution of the collapse. To perform the simulations, we employed a one-dimensional collapse model that self-consistently and time-dependently combines hydrodynamics with chemical and radiative transfer simulations. The dust opacity was updated on the fly based on the ice growth as a function of the location in the core. The results of the fully dynamical model were compared against simulations run with different values of fixed ice thickness. We found that the ice thickness increases quickly and reaches a saturation value (as a result of a balance between adsorption and desorption) of approximately 90 monolayers in the central core (volume density ~104 cm−3), and several tens of monolayers at a volume density of ~103 cm−3, after only a few 105 yr of evolution. The results thus exclude the adoption of thin (approximately ten monolayer) ices in molecular cloud simulations except at very short timescales. However, the differences in abundances and the dust temperature between the fully dynamic simulation and those with a fixed dust opacity are small; abundances change between the solutions generally within a factor of two only. The assumptions on the dust opacity do have an effect on the collapse dynamics through the influence of the photoelectric effect on the gas temperature, and the simulations take a different time to reach a common central density. This effect is, however, small as well. In conclusion, carrying out chemical simulations using a dust temperature corresponding to a fixed opacity seems to be a good approximation. Still, although at least in the present case its effect on the overall results is limited – as long as the grains are monodisperse – ice growth should be considered to obtain the most accurate representation of the collapse dynamics. We have found in a previous work that considering a grain size distribution leads to a complicated ice composition that depends on the grain size nonlinearly. With this in mind, we will carry out a follow-up study where the influence of the grain size on the present simulation setup is investigated. [ABSTRACT FROM AUTHOR]

An analytical model has been developed to describe the electron transport in semiconductor photocathodes exposed to microwave radiation from radiofrequency photoguns. The considered model, whose applicability framework is presented, makes it possible to obtain an analytical expression for the photocurrent profile, which potentially allows a more accurate simulation of the operation regime of radiofrequency photoguns for generating ultrashort (pico- and subpicosecond) electron bunches. The dependence of photocurrent fronts on the model parameters has been considered and discussed. The main directions for the development of the model have been outlined. [ABSTRACT FROM AUTHOR]

In the last twenty years, nanofabrication progress has allowed for the emergence of a new photodetector family, generally called low-dimensional solids (LDSs), among which the most important are two-dimensional (2D) materials, perovskites, and nanowires/quantum dots. They operate in a wide wavelength range from ultraviolet to far-infrared. Current research indicates remarkable advances in increasing the performance of this new generation of photodetectors. The published performance at room temperature is even better than reported for typical photodetectors. Several articles demonstrate detectivity outperforming physical boundaries driven by background radiation and signal fluctuations. This study attempts to explain these peculiarities. In order to achieve this goal, we first clarify the fundamental differences in the photoelectric effects of the new generation of photodetectors compared to the standard designs dominating the commercial market. Photodetectors made of 2D transition metal dichalcogenides (TMDs), quantum dots, topological insulators, and perovskites are mainly considered. Their performance is compared with the fundamental limits estimated by the signal fluctuation limit (in the ultraviolet region) and the background radiation limit (in the infrared region). In the latter case, Law 19 dedicated to HgCdTe photodiodes is used as a standard reference benchmark. The causes for the performance overestimate of the different types of LDS detectors are also explained. Finally, an attempt is made to determine their place in the global market in the long term. [ABSTRACT FROM AUTHOR]

Coherent light has revolutionized scientific research, spanning biology, chemistry and physics. To delve into ultrafast phenomena, the development of high-energy, highly tunable light sources is instrumental. Here, the photoelectric effect is a pivotal tool for dissecting electron correlations and system structures. Particularly, above-threshold ionization (ATI), characterized by the simultaneous absorption of several photons leading to a final electron energy well above the ionization threshold, has been widely explored, both theoretically and experimentally. ATI decouples laser field effects from the structural information carried by photoelectrons, particularly when utilizing ultrashort pulses. In this contribution, we study ATI driven by polarization-crafted (PC) pulses, which offer precise scanning over the electron momentum, through an accurate change of the polarization state. PC pulses enable the manipulation of photoelectron momentum distributions, opening up new avenues for understanding and harnessing coherent light. Our work explores how structured light could allow for a proper understanding of emitted photoelectrons momentum distributions in order to distinguish between light structure effects and target structure effects. [ABSTRACT FROM AUTHOR]

Solar irradiation can efficiently promote the kinetics of the oxygen evolution reaction (OER) during water splitting, where heterojunction catalysts exhibit excellent photoresponsive properties. However, insights into the origins of photoassisted OER catalysis remain unclear, especially the interfaced promotion under convergent solar irradiation (CSI). Herein, novel allotropic Co5.47N/CoN heterojunctions were synthesized, and corresponding OER mechanisms under CSI were comprehensively uncovered from physical and chemical aspects using the in situ Raman technique and electrochemical cyclic voltammetry method. Our results provide a unique mechanism where high‐energy UV light promotes the Co3+/4+ conversion process in addition to the ordinary photoelectric effect excitation of the Co2+ material. Importantly, visible light under CSI can produce a photothermal effect for Co2+ excitation and Co3+/4+ conversion, which promotes the OER significantly more than the usual photoelectric effect. As a result, Co5.47N/CoN (containing 28% CoN) obtained 317.9% OER enhancement, which provides a pathway for constructing excellent OER catalysts. [ABSTRACT FROM AUTHOR]

Introduction: Negative oxygen ions are produced by plants through photosynthesis, utilizing "tip discharge" or the photoelectric effect, which has various functions such as sterilization, dust removal, and delaying aging. With global warming, high temperatures may affect the ability of Phalaenopsis aphrodite Rchb. f. to produce negative oxygen ions. P. aphrodite is commonly used in modern landscape planning and forest greening. Methods: In this study, P. aphrodite was selected as the research object. By artificially simulating the climate, the control group (CK) and the high temperature stress group (HS) were set up in the experiment. Results: The study found that compared with the control group, the ability of P. aphrodite to produce negative oxygen ions significantly decreased when exposed to high temperature stress. Meanwhile, under high temperature stress treatment, peroxidase content increased by 102%, and proline content significantly increased by 35%. Discussion: Redundancy analysis results indicated a significant correlation between the root endophytic microbial community of P. aphrodite and negative oxygen ions, as well as physiological indicators. Under high temperature stress, P. aphrodite may affect the regulation of physiological indicators by modifying the composition of root endophytic microbial communities, thereby influencing the ability to release negative oxygen ions. [ABSTRACT FROM AUTHOR]

The morphology of the photoactive layer plays an important role in both the photoelectric effect and device performance of solution‐processed organic solar cells (OSCs). Optimizing the morphology requires precise control over the complex film formation kinetics, which are influenced by a range of factors from the solution state to the solid‐film state. This review delves into the in situ characterization technologies employed to understand the active layer formation process and explores strategies for controlling film formation during key stages, including solution aggregation, nucleation, crystal growth, and phase separation. Special attention is given to the mechanism by which these strategies enable real‐time morphology control during the printing process and their potential to facilitate direct printing of active layers with optimized morphology. The goal is to offer valuable insights and guidance for managing film formation kinetics in solution‐processed OSCs, ultimately addressing the challenges of real‐time morphology control in scale‐up printing and paving the way for high‐throughput production of post‐processing‐free devices. [ABSTRACT FROM AUTHOR]

Based on the first principle, the change of photoelectric properties of non-metal-doped CrS2 under biaxial tension was studied. The formation energy indicates that the doping system is stable. Studies have shown that the partial doping system achieves a semiconductor metal phase transition. The strain opens the bandgap of the F-doped system, and the system changes from metal to n-type semiconductor. The Te-doped system realizes the transition from indirect bandgap to direct bandgap under the adjustment of 2% strain. The O and Se doping systems realize the reverse regulation of the bandgap under strain, and the conductivity gradually increases with the increase of strain. The absorption efficiency of Te doping under a certain strain is significantly enhanced, the static dielectric properties of the F doping system are increased by more than two times, the absorption spectrum response range is increased, and the absorption capacity of the system is enhanced. This lays a foundation for applying monolayer CrS2 in microelectronics and optoelectronics. [ABSTRACT FROM AUTHOR]

New energy sources such as solar energy have been developed and utilized due to the shortage of non-renewable energy, and photoelectric materials have attracted more attention, accordingly. Moreover, flexible optoelectronic devices are crucial in the fields of wearable artificial intelligence, portable energy, and smart medical care. At present, photoelectric devices based on traditional perovskite cobalt oxide rigid films have problems such as inability to bend and deformation, which limits their application environment. Here, natural mica with atomically flat surface, high thermal stability, high transparency and good mechanical flexibility was selected as the substrate for preparing a series of LaCoO 3 flexible photoelectric films. These films exhibit excellent photoelectric properties and flexible properties. More importantly, the flexible film still has fast response speed and reproducible light response after 500 bending cycles. It reveals that all-inorganic perovskite LaCoO 3 is a promising candidate for designing high-performance, flexible and wearable optoelectronic devices. [Display omitted] [ABSTRACT FROM AUTHOR]

Recently, novel two-dimensional (2D) crystals, MSi2N4 (M = Mo, W) materials, have been successfully synthesized experimentally and have comparable excellent catalytic properties as that of MoS2. The suitability of MA2Z4 family materials in photocatalytic water splitting can't be fully determined by whether the bandgap edge of the material cross the standard redox potential of water. Photoelectric properties and electron–hole separation are also critical factors to be considered. We investigated the bandgap edge positions and the photoelectric and the electron–hole excitation properties of 2D MoSi2N4 and its family of materials (CrSi2N4, WSi2N4) in water by first-principles calculations, and the results indicate that WSi2N4 may be a relatively high-performing photocatalyst. Relative to the MoSi2N4 bandgap (1.74 eV), the bandgap of WSi2N4 is 2.06 eV, and the conduction-band minimum edge band potential (−0.42 eV) is close to the hydrogen precipitation potential in water at pH = 7. The bandgaps of the MSi2N4 (M = Mo, W) materials cross the water redox potential (1.23 eV), and both have favorable adsorption for H2O molecules. However, compared with the absorption spectrum and excited states of MoSi2N4 in water, WSi2N4 exhibits a broader and more enhanced visible light absorption range and intensity as well as a higher electron–hole separation. 2D WSi2N4 could achieve the half-reaction of photocatalytic water splitting under visible light irradiation, and the photogenerated electrons in the conduction band can spontaneously reduce H+ ions to hydrogen, suggesting that WSi2N4 might be composed of a heterogeneous structure with other photocatalysts to accomplish the redox of water. [ABSTRACT FROM AUTHOR]

Various defects of nanocomposites inevitably bring some harmful effects on their photoelectric performance, especially considering that interface defects seriously hinder the carrier interfacial transfer. Here, the interface optimization can be realized between graphitic carbon nitride (C3N4) and CoP co-catalyst by the introduction of good conductive carbon nanosheets (CNs). As a result, the defect density of synthesized C3N4/CNs/CoP is reduced to 1.40 × 1012 cm−3 from 2.55 × 1012 cm−3 of C3N4/CoP, and its interface impedance is correspondingly reduced to 34% of that of C3N4/CoP. Therefore, the optimal H2 evolution rate of 5.26 mmol g−1 h−1 and apparent quantum efficiency of 9.27% at 420 nm are realized, which are 4.8 and 8.1 times that of C3N4/CoP photocatalyst in the absence of CNs, respectively. This work provides a general solution to reduce defect density and carrier transfer resistance in nanocomposites by the introduction of a highly conductive buffer layer. [ABSTRACT FROM AUTHOR]

Partial breast irradiations with electronic brachytherapy or kilovoltage intraoperative radiotherapy devices such as Axxent or INTRABEAM are becoming more common every day. Breast is mainly composed of glandular and adipose tissues, which are not always clearly disentangled in planning breast CTs. In these cases, breast tissues are replaced with an average soft tissue, or even water. However, at kilovoltage energies, this may lead to large differences in the delivered dose, due to the dominance of photoelectric effect. Therefore, the aim of this work was to study the effect on the dose prescribed in breast with the INTRABEAM device using different soft tissue assignment strategies that would replace the adipose and glandular tissues that constitute the breast in cases where these tissues cannot be adequately distinguished in a CT scan. Dose was computed with a Monte Carlo code in five patients with a 3 cm diameter INTRABEAM spherical applicator. Tissues within the breast were assigned following six different strategies: one based on the TG-43 recommendations, representing the whole breast as water of unity density, another one also water-based but with CT derived density, and the other four also based on CT-derived densities, using a single tissue resulting from different mixes of glandular and adipose tissues. These were compared against the reference dose computed in an accurately segmented CT, following TG-186 recommendations. Relative differences and dose ratios between the reference and the other tissue assignment strategies were obtained in three regions of interest inside the breast. Dose planning in water-based tissues was found inaccurate for breast treatment with INTRABEAM, as it would incur in up to 30% under-prescription of dose. If accurate soft tissue assignments in the breast cannot be safely done, a single-tissue composition of 80% adipose and 20% glandular tissue, or even a 100% adipose tissue, would be recommended to avoid dose under-prescription. [ABSTRACT FROM AUTHOR]

A pioneering integration of oxide semiconductor memristors with optoelectronic features is presented, surpassing binary limitations to realize multi‐valued synaptic operations. Through Pt/Ga2O3/Pt memristors, their structural and electronic attributes via atomic force microscopy, X‐ray diffraction, and X‐ray photoelectron spectroscopy are explored. Demonstrating unipolar resistance switching with remarkable endurance and retention, the devices exhibit intricate light‐resistance correlations, yielding substantial photoelectric effects in distinct resistance states. Investigating synaptic behaviors, potentiation, and depression akin to biological synapses are unveiled, facilitating learning and memory processes. The standout achievement lies in attaining quaternary memory storage within a single device. Empirical data and simulations validate this concept, showcasing the potential for encoding and sustaining multiple memory states. This innovation heralds transformative possibilities, emphasizing oxide semiconductor memristors as a gateway to quaternary memory storage and enhanced synaptic functions. In essence, this work pioneers optoelectronic synaptic devices with expanded memory capabilities. [ABSTRACT FROM AUTHOR]

Copyright of Polymer Materials Science & Engineering is the property of Sichuan University, Polymer Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Response time is a crucial factor limiting the performance of two-dimensional material-based photodetectors. The underlying mechanisms of response have recently garnered significant attention in the ongoing research. Supported ReS2 on substrates has been found to be predominantly governed by the photofloating gate effect, known to be slower compared to photoelectric effects. In this study, we present findings demonstrating suspended ReS2 devices. Removing the substrate results in a substantial enhancement in optical response by an order of magnitude compared to substrate-supported devices. Deep trap states induced by inherent defects are identified as the primary contributors to prolonged response times. Engineering these ReS2 trap states through defect manipulation can significantly improve response times. Here, we effectively modulate the response speed of ReS2 through gentle oxygen plasma treatments. The response speed of ReS2 is improved by two orders of magnitude. Under the optimal processing conditions of 50 W, 30 Pa, and 10 s, we observed rising and falling response times of 45 and 106 ms, respectively, under illumination at a wavelength of 637 nm. Additionally, we demonstrate that the input–output characteristic of photocurrent provides valuable insights into the underlying opto-physical processes responsible for generating photocurrent. [ABSTRACT FROM AUTHOR]

Creating oxygen vacancy in tungsten trioxide (WO3) has been considered as an effective strategy to improve the photocatalytic performance for degrading organic pollutants. In this study, oxygen vacancies were introduced into WO3 by thermal treatment under Ar atmosphere and their proportion was changed by setting different treatment times. WO3−x samples show better photoelectric properties and photocatalytic degradation performance for carbamazepine (CBZ) than an oxygen-vacancy-free sample, and WO3−x with the optimal proportion of oxygen vacancies is obtained by thermal treatment for 3 h in 550 °C. Furthermore, it discovers that the surface oxygen vacancies on WO3−x would be recovered when it is exposed to air, resulting in a bulk oxygen vacancy dominating WO3−x (bulk-WO3−x). The bulk-WO3−x exhibited much higher degradation efficiency for CBZ than WO3−x with both surface and bulk oxygen vacancies. The mechanism study shows bulk-WO3−x mainly degrades the CBZ by producing OH radicals and superoxide radicals, while oxygen-vacancy-free sample mainly oxidizes the CBZ by the photoexcited hole, which requires the CBZ to be adsorbed on the surface for degradation. The radical generated by bulk-WO3−x exhibits stronger oxidizing capacity by migrating to the solution for CBZ degradation. In summary, the influence of oxygen vacancy on photocatalytic degradation performance depends on both the proportion and location distribution and could lie in the optimization of the photodegradation mechanism. The results of this study could potentially broaden our understanding of the role of oxygen vacancies and provide optimal directions and methods for oxygen vacancy regulation for photocatalysts. [ABSTRACT FROM AUTHOR]

Merging the functionality of an organic field-effect transistor (OFET) with either a light emission or a photoelectric effect can increase the efficiency of displays or photosensing devices. In this work, we show that an organic semiconductor enables a multifunctional OFET combining electroluminescence (EL) and a photoelectric effect. Specifically, our computational and experimental investigations of a six-ring thiophene-phenylene co-oligomer (TPCO) revealed that this material is promising for OFETs, light-emitting, and photoelectric devices because of the large oscillator strength of the lowest-energy singlet transition, efficient luminescence, pronounced delocalization of the excited state, and balanced charge transport. The fabricated OFETs showed a photoelectric response for wavelengths shorter than 530 nm and simultaneously EL in the transistor channel, with a maximum at ~570 nm. The devices demonstrated an EL external quantum efficiency (EQE) of ~1.4% and a photoelectric responsivity of ~0.7 A W–1, which are among the best values reported for state-of-the-art organic light-emitting transistors and phototransistors, respectively. We anticipate that our results will stimulate the design of efficient materials for multifunctional organic optoelectronic devices and expand the potential applications of organic (opto)electronics. [ABSTRACT FROM AUTHOR]

Covalent organic framework (COF) materials have aroused tremendous interest in photocatalytic applications due to their tunable pore structure and photoelectric properties. The regular nanopore of COF itself presents a strongly confinement effect, which provides a unique regulatory effect for photons, electrons, protons, and other quantum‐scale reaction groups. However, due to the weak surface electron coupling and transfer ability between the reactive groups and basic elements of its structural units, the activity of pure COFs photocatalyst is still not satisfactory. Therefore, the confinement modification strategy of confining low‐dimension entities within COFs has been proposed, thus realizing new active sites construction and band structure regulation has been intensively studied, but yet to be summarized systematically. In this paper, the semi‐conductivity of COFs is discussed dialectically based on photocatalytic thermodynamics, and the influence of internal linkage motifs and stacking behaviors on the band structure is collected. Then, the basic understanding of confinement characteristics and their influence on photocatalytic performance in dynamics is further explained according to the spatial dimension classification of low‐dimension entities. And the application and mechanism of these COF‐based confined catalysts in energy conversion reactions are discussed in detail. Lastly, the current challenges and development prospects of COF‐based confined hetero‐photocatalysts are discussed. [ABSTRACT FROM AUTHOR]

Heterostructure engineering is an effective technology to improve photo-electronic properties of two dimensional layered semiconductors. In this paper, based on first principles method, we studied the structure, stability, energy band, and optical properties of ZnSe/SnSe heterostructure change with film layer. Results show that all heterostructures are the type-II band arrangement, and the interlayer interaction is characterized by van der Waals. The electron concentration and charge density difference implies the electron (holes) transition from SnSe to monolayer ZnSe. By increasing the layer of SnSe films, the quantum effects are weakened leading to the band gap reduced, and eventually show metal properties. The optical properties also have obvious change, the excellent absorption ability of ZnSe/SnSe heterostructures mainly near the infrared spectroscopy. These works suggest that ZnSe/SnSe heterostructure has significant potential for future optoelectronic applications. [ABSTRACT FROM AUTHOR]

Plasma confinement was succeeded by an optoelectronic system with the aid of a vacuum ultraviolet (VUV) light source, called the photoemission-assisted plasma system. The photoemission-assisted plasma was generated by utilizing photoelectrons from the substrate cathode. The photoelectrons were emitted from the substrate by external VUV irradiation via the photoelectric effect and then worked as initial electrons triggering the plasma generation. The photoemission-assisted plasma was confined with bright luminescence in an argon atmosphere by controlling the flow rate and pressure. The plasma confinement survived at up to 6400 Pa, which was much higher than the pressure estimated from the current–voltage characteristics. These results suggested that the area exhibiting luminescence dominated by the γ regime becomes small as the argon flow rate increases; however, the area does not vanish because the VUV-excited photoelectrons are sufficiently supplied. The residual area is dominated by the α regime without luminescence. Thus, the photoemission-assisted plasma seems to be confined on the balance between α and γ regimes. Because the current in the α-regime area is one hundredth in magnitude compared with that in the γ-regime area, the actual current density results in over 40 times with strong luminescence. This confined plasma with certain voltage and current condition may be expected for developing a new plasma reaction system and for application in semiconductor engineering. [ABSTRACT FROM AUTHOR]