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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]

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]

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]

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]

AbstractIn this study, Ti2O3 thin films were successfully produced using magnetron sputtering. Through orthogonal gradient experiments, the impact of substrate temperature, sputtering vacuum, RF power, and sputtering duration on surface morphology, roughness, physical structure, and resistivity was investigated. Various analytical techniques were employed, including AFM and SEM for surface morphology observation, XRD and Raman for qualitative physical structure analysis, XPS for elemental valence examination, and the four‐probe method for resistivity measurements. The study identified optimal growth conditions for Ti2O3 films, demonstrating a low resistivity of 2.66 × 10−3 Ω cm under the following conditions: RF power of 200 W, sputtering vacuum of .6 Pa, substrate temperature of 600°C, and sputtering duration of 60 min. Additionally, the sensor arrays were efficiently fabricated using the Lift‐off method to evaluate the photoelectric performance of the films. A light responsiveness of approximately 6 µA/W was observed in the device when illuminated with 950 nm light for 10 s. This finding carries important implications for the use of Ti2O3 thin films in future photoelectric devices. [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]

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]

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]

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]

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]

Metal halide perovskites (MHPs) are considered ideal photovoltaic materials due to their variable crystal material composition and excellent photoelectric properties. However, this variability in composition leads to complex crystallization processes in the manufacturing of Metal halide perovskite (MHP) thin films, resulting in reduced crystallinity and subsequent performance loss in the final device. Thus, understanding and controlling the crystallization dynamics of perovskite materials are essential for improving the stability and performance of PSCs (Perovskite Solar Cells). To investigate the impact of crystallization characteristics on the properties of MHP films and identify corresponding modulation strategies, we primarily discuss the relevant aspects of MHP crystallization kinetics, systematically summarize theoretical methods, and outline modulation techniques for MHP crystallization, including solution engineering, additive engineering, and component engineering, which helps highlight the prospects and current challenges in perovskite crystallization kinetics [ABSTRACT FROM AUTHOR]

Cesium lead halide perovskite nanocrystals (PNCs) are promising candidates for photoelectric applications due to their remarkable optoelectronic properties. However, the poor stability of PNCs, especially oleic acid (OA)/oleylamine (OAm)‐capped CsPbI3, is the main obstacle to their commercialization. In this study, CsPbI3 PNCs with long‐term stability are prepared through synergistic passivation of n‐octylphosphonic acid (OPA) and (3‐aminopropyl) triethoxysilane (APS). OPA provides a stronger binding affinity to passivate surface defects, while the SiO2 layer formed by APS can further reduce ligand detachment and block the access of external factors to the PNCs. The stability of OPA/APS‐capped CsPbI3 PNCs can be synergistically enhanced in comparison with that of OA/OAm‐capped PNCs, the fluorescence of which can be also increased significantly. Employing the high‐performance OPA/APS‐capped CsPbI3 PNCs as color‐converting materials, a white light‐emitting diode with a color coordinate of (0.33 and 0.32) and a wide color gamut of 126% National Television Standard Committee color space is fabricated. [ABSTRACT FROM AUTHOR]

Background: Silicon (Si) is a possible sensor material for photon counting detectors (PCDs). A major drawback of Si is that roughly two‐thirds of x‐ray interactions in the diagnostic energy range are Compton scattering. Because Compton scattering is an energy‐insensitive process, it is commonly assumed that Compton events retain little spectral information. Purpose: To quantify how much information can be recovered from Compton scattering events in models of Si PCDs. Methods: We built a simplified model of Si interactions including two interaction mechanisms: photoelectric effect and Compton scattering. We considered three different binning options that represent strategies for handling Compton events: in Compton censoring, all events under 38 keV (the maximum energy possible from Compton scattering for a 120 keV incident photon) were discarded; in Compton counting, all events between 1 and 38 keV were placed into a single bin; in Compton binning, all events were placed into energy bins of uniform width. These were compared to the ideal detector, which always recorded the correct energy (i.e., 100% photoelectric effect). Every photon was assumed to interact once and only once with Si, and the energy bin width was 5 keV. In the primary analysis, the Si detector was irradiated with a 120 kV spectrum filtered by 30 cm of water, with 99.5% of the arriving spectrum above 38 keV so that there was good separation between photoelectric effect and Compton scattering, and the figures of merit were the Cramér–Rao lower bound (CRLB) of the variance of iodine and water basis material decomposition images, as well as the CRLB of virtual monoenergetic images (i.e., linear combinations of material images) that maximize iodine CNR or water CNR. We also constructed a local linear estimator that attains the CRLB. In secondary analyses, we applied other sources of spectral distortion: (1) a nonzero minimum energy threshold; (2) coarser, 10 keV energy bins; and (3) a model of charge sharing. Results: With our chosen spectrum, 67% of the interactions were Compton scattering. Consistent with this, the material decomposition variance for the Compton censoring model, averaged over both basis materials, was 258% greater than the ideal detector. If Compton events carried no spectral information, the Compton counting model would show similar variance. Instead, its basis material variance was 103% greater than the ideal detector, implying that Compton counts indeed carry significant spectral information. The Compton binning model had a basis material variance 60% greater than the ideal detector. The Compton binning model was not affected by a 5 keV minimum energy threshold, but the variance increased from 60% to 107% when charge sharing was included and to 78% with coarser energy bins. For optimized CNR images, the average variance was 149%, 12%, and 10% higher than the ideal detector for the Compton censoring, counting, and binning models, reinforcing the hypothesis that Compton counts are useful for detection tasks and that precise energy assignments are not necessary. Conclusions: Substantial spectral information remains after Compton scattering events in silicon PCDs. [ABSTRACT FROM AUTHOR]

A series of probe measurements of low-temperature plasma parameters ahead of the front of the incident shock wave was carried out using a double-diaphragm shock tube DDST-M of the Institute of Mechanics of Moscow State University. Such investigations are needed for determining the electron concentration in front of the shock wave. This characteristic is important for the safety of the spacecraft flight since it's directly affects to communication problems during the descent and is necessary for adequate description of kinetic processes behind the shock wave. Nitrogen, oxygen, air, and argon were used as working gases. The results obtained make it possible to describe the processes of the photoelectric effect and photoionization of gas particles due to the hard radiation of a shock-heated medium, to evaluate the effect of these processes on the change in the probe potential, and to measure the electron concentration. The probe measurements were synchronized with the registration of the light flux, which was carried out using an avalanche photodiode and a 9-frame video camera located at the end of the shock tube. Data from the camera and piezoelectric sensors record the dynamics of the opening of the diaphragm, as well as the process of formation of a shock wave in the gas under study. • Electron emission due to the photoelectric effect. • Photoionization of the gas ahead of the shock front. • Estimation of electron concentration from the probe measurement. [ABSTRACT FROM AUTHOR]

Electron-pulse probing of fast laser-induced processes has allowed the direct observation of the structural dynamics in matter with a high spatiotemporal resolution. A thin gold film has appeared to be a convenient photocathode, and photoelectron emission has been induced by femtosecond ultraviolet radiation with a photon energy of about 4.65–4.75 eV (in particular, ω 4.65 eV for the third harmonic of the Ti:sapphire laser). For the linear photoelectric effect, this energy contradicts the reference work function WAu 5.1–5.3 eV of pure metal. Reasons for such contradiction have been analyzed and good agreement with experimental data has been reached with a model proposed for the generation of photoelectron pulses. [ABSTRACT FROM AUTHOR]

Field effect transistors have shown promising performance as terahertz (THz) detectors over the past few decades. Recently, a quantum phenomenon, the in-plane photoelectric effect, was discovered as a novel detection mechanism in gated two-dimensional electron gases (2DEGs), and devices based on this effect, photoelectric tunable-step (PETS) THz detectors, have been proposed as sensitive THz detectors. Here, we demonstrate a PETS THz detector based on GaAs/AlGaAs heterojunction using a dipole antenna. We investigate the dependence of the in-plane photoelectric effect on parameters including the dimensions and the operating temperature of the device. Two figures of merit within the 2DEG, the maximum electric field and the radiation-induced ac-potential difference, are simulated to determine the optimal design of the PETS detector antenna. We identify the optimal antenna gap size, metal thickness, and 2DEG depth, and demonstrate the first PETS detector with a symmetric dipole antenna, which shows high-speed detection of 1.9 THz radiation with a strong photoresponse. Our findings deepen the understanding of the in-plane photoelectric effect and provide a universal guidance for the design of future PETS THz detectors. [ABSTRACT FROM AUTHOR]

Renewable energy sources and the CO2 emissions in the atmosphere are predicted to play a very important role in attaining the climate neutrality by the half of this century. The rapid depletion of fossil fuel reserves and the looming threat of climate change have intensified the global pursuit of renewable energy sources as a viable alternative. The positive aspect of using renewable energy sources is that this kind of resources can easily supply the worlds energy needs. Despite the fact that we cannot capture all this energy, harnessing less than 0.02 % would be enough to cover all the necessary energy needs. Obstacles to expanding solar power generation involve the substantial cost of manufacturing solar cells and the dependency on weather conditions. The efficiency and performance of photovoltaic panels are inherently tied to environmental variables, prominently including climate factors. This article investigates the intricate relationship between climatic conditions and photovoltaic panel yields, offering crucial insights for optimizing the solar energy generations. It has been analysed the impact of environmental factors such as ambient temperature, wind speed and air humidity above the yield of photovoltaic panels. For each environmental factor, the variable conditions were simulated to highlight their correlation with positive or negative effect they have on the yield of a photovoltaic panel. By perusing this material, readers can develop a comprehensive grasp of how the environment conditions can influence the production of electricity using the photoelectric effect. Leveraging empirical data and simulation models using the PVsyst software, the analysis discerns regional variations and seasonal fluctuations in photovoltaic panels yields according to diverse climatic factors regimes. [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]

Among the practical applications of Quantum Physics, photoluminescence has stood out in different contexts in Engineering and Architecture. Due to the photoelectric effect, certain substances emit photons after being exposed to solar energy. In research in Mexico and Europe, these substances were applied to obtain a photoluminescent effect on bicycle paths. The objective of the research is to investigate the behavior of polymeric residues with the luminescent effect of rare-earth materials in the production of concrete artifacts to illuminate pedestrian and cyclist paths. The concrete blocks were produced with the addition of polymeric recycling waste and luminescent materials, exposed to solar radiation, and tested for mechanical strength. The results of the experiments showed that the polymer residue in concrete significantly increases photon emission, especially when it is processed by extrusion. Although the mixture of photoluminescent materials and polymers reduces the strength of concrete, it still met research objectives for a product meant to illuminate pedestrian and cyclist paths.

Incorporating functional organic linkers into supertetrahedral chalcogenolate cluster-based materials is an effective synthetic strategy to expand structural diversity and generate tunable optical and photoelectric properties arising from synergistic effects. Herein, a mixed ligand engineering approach was adopted to design a supertetrahedral cluster-based assembled material [(Cd6Ag4(SPh)16(TPPA)(BPE)0.5)·2DMF]n (denoted as SCCAM-3) with a 2D bilayer architecture and broader visible-light absorption. Interestingly, SCCAM-3 demonstrates a long-lived afterglow at 83 K and efficient photocatalytic activity for degrading tetracycline in water. [ABSTRACT FROM AUTHOR]

Carbon dots with good photoelectric properties are usually used as photocatalysts and electrocatalysts, but the good catalytic performance of carbon dots as nanomaterials for thermal catalysis is ignored. Herein, the application of novel efficient catalysts based on carbon dots for the transformation of carbon dioxide (CO2) to carbonates under solvent-free conditions is described. Carbon dots containing carboxyl, hydroxyl, and amine groups were prepared by a microwave technique and employed together with KI, which showed exceptional catalytic activity in the cycloaddition of carbon dioxide with different epoxides. In addition, the catalyst was easily reusable and had stable recyclability. And the catalyst displayed outstanding catalytic performance due to the synergistic effect of carboxyl (–COOH), hydroxyl (–OH), and amine (–NH) groups. [ABSTRACT FROM AUTHOR]

Present study aims to locate potential reservoir zones in the Paleocene, Eocene and Oligocene sequences by analysing well log data of nine vertical wells in the exploration block MB-OSN-2004/1 in the Bombay offshore basin, Gulf of Cambay, India. The geophysical logs such as gamma-ray (GR), caliper (Cali), resistivity (LLD, LLS, and MSFL), photoelectric effect (PEE), neutron porosity (NPHI), and density (RHOB) are used to study the petrophysical characteristics of the identified reservoirs in this field. The relevant information from other sources like available report, mud log, and other open hole wireline log data, and local knowledge about the field are integrated with the petrophysical analysis. The cross-plots and mud log data show that the wells mainly consist of three types of lithology: shaly-sand, shale, and limestone, however, coal layers and pyrite are present at some places. Cross plots of thorium and potassium (from spectral gamma-ray log) show that the type of clay is mixed-layers of illite, montmorillonite and kaolinite in the Pipavav and Panna formations. Three of the nine drilled wells C-47-1, MTC-1, and MB-3-1 are identified by the petrophysical investigation as gas-bearing, principally in the Pipavav and Panna formations, with saturation ranging from 55% to 60% and porosity varying from 10% to 40%. Gas-bearing layers' thickness varies from 5 to 40 m and are primarily composed of clastic sediment with mixed carbonates in some locations. The remaining wells are water-bearing because the wells penetrating the silt formations are abundant in clay minerals, which keep the reservoir from releasing fluid and decrease its permeability. In addition, gas cannot rise because impervious shale layers are present in the columns of sand and calcareous sand. [ABSTRACT FROM AUTHOR]

Photoelectric catalysis is a green and efficient way to degrade pollutants, which has been paid more and more attention by researchers. Among them, Bi2WO3 has been proved to have excellent photocatalytic oxidation activity on its {001} facets. In this study, {001}-oriented facets with high exposure were successfully integrated into Bi2WO6 nanoplate arrays (Bi2WO6 NAs) to create a photoelectrode. This structure was grown in situ on an indium tin oxide (ITO) substrate. To promote photogenerated carrier separation efficiency and reduce agglomeration of Bi2WO6 photocatalysts, the electrochemical deposition of NiFe–layered double hydroxide (NiFe-LDH) and Ti3C2 (MXene) were introduced in this research to synergistically catalyze pollutant degradation. Morphology, spectral characterization, and electrochemical analysis jointly confirmed that the outstanding performance of hole capture behavior with LDH and electron conduction properties with MXene were the main reasons for the improvement in catalytic activity of the photoelectrode. Taking bisphenol A (BPA) as the model pollutant, the rate constant k of the NiFe-LDH/Ti3C2/Bi2WO6 NAs photoelectrode reaches 0.00196 min−1 under photoelectrocatalytic (PEC) conditions, which is 4.5 times that of the pure Bi2WO6 NAs photoelectrode. This work provides a new way to improve the reaction kinetics of the PEC degradation of pollutants. [ABSTRACT FROM AUTHOR]

The reported BiFe0.9Co0.1O3 film presents an interesting magnetic field tunning effect on the photoelectric properties and photoluminescence spectra. The change rate of the photocurrent up to 123.6% was achieved when applying a 400 Oe magnetic field to the film, which is attributed to the spin scattering of photoelectrons in the film. The experimental result of the magnetic field tuning photoluminescence spectra indicates that the magnetic field inhibits the radiative transition of the photogenerated carriers in the thin film and therefore reduces the intensity of photoluminescence. This research provides a basis for the research and application of devices in the field of multifunctional photoelectric materials. [ABSTRACT FROM AUTHOR]

Chemosensor technology for trace gases in the air always aims to identify these compounds and then measure their concentrations. For identification, traceable methods are sparse and relate to large appliances such as mass spectrometers. We present a new method that uses the alternative traceable measurement of the ionization energies of trace gases in a way that can be miniaturized and energetically tuned. We investigate the achievable performance. Since tunable UV sources are not available for photoionization, we take a detour via impact ionization with electrons, which we generate using the photoelectric effect and bring to sharp, defined energies on a nanoscale in the air. Electron impact ionization is thus possible at air pressures of up to 900 hPa. The sensitivity of the process reaches 1 ppm and is equivalent to that of classic PID. With sharpened energy settings, substance identification is currently possible with an accuracy of 30 meV. We can largely explain the experimental observations with the known quantum mechanical models. [ABSTRACT FROM AUTHOR]

In this paper, the effects of transition metal doping on the electronic structure of monolayer NbS2 were studied through the first principles. The electronic structure changes caused by doping transition metal (TM) atoms were recorded, including the energy band, the density of states, binding energy, and optical properties. Studies show that all doping systems are metal. Still, under strain regulation, some doping systems offer an indirect bandgap; NbS2 transforms into a narrow bandgap diluted semiconductor and can improve the activity. Doping atoms lead to n (p) type doping in NbS2. Regarding optical properties, IVB group metals are selected as the typical dopant of three periods. Composite NbS2 has excellent reflector characteristics and can be applied to infrared and ultraviolet regions. The spectral response and electromagnetic wave absorption range of low-energy areas are also improved. This study effectively solves the problem of impurity states introduced by doping and provides a solution for the doping modification of monolayer NbS2, which will lay a foundation for nanoelectronics. [ABSTRACT FROM AUTHOR]

Perovskite solar cells, which are considered the third generation of new concept solar cells, are known for their high photoelectric conversion efficiency, low cost, and flexible processing advantages, and have been rapidly development in recent years. its photoelectric conversion efficiency is gradually comparable to that of silicon cells and has been close to the level required for industrial applications. However, the main problem with the industrial application of perovskite solar cells is their stability. Researchers need to solve the biggest problem of how to maintain high efficiency for a long time in perovskite solar cells. Encapsulation is currently being widely studied as a solution to the external stability issue of perovskite solar cells. A good encapsulation can not only solve the stability problem of the device but also ensure the safety of the device and extend the service life. The stability of perovskite solar cells and the conditions for testing it are briefly described in this paper. In the end, the various encapsulation structures, techniques, and materials for perovskite solar cells are explained. The continuous advancement of encapsulation research will lead researchers to optimize and solve existing problems, leading to the eventual industrialization of perovskite solar cells on a large scale. [ABSTRACT FROM AUTHOR]

Context: In this study, the electronic structures and optical properties of the pure MoSe2 and O-doped MoSe2 systems under different shear deformations are calculated based on the first-principles approach. It is hoped to provide new possibilities for the design of novel controllable optoelectronic devices and to provide guidance for the application of MoSe2 in the field of optoelectronic devices. The findings indicate that both pure MoSe2 and O-doped MoSe2 systems are somewhat impacted by shear deformation. The pure MoSe2 undergoes a transition from direct to indirect and then to direct bandgap under shear deformation, but still maintains the semiconductor properties. The bandgap of the doped system changes from a direct to an indirect bandgap at 8% shear deformation. According to the examination of the density of states, we find that the density of states of the pure MoSe2 system is mainly contributed by the Mo-d and Se-p orbitals, and the total density of states of the system after O-atom doping mainly originates from the results of the contributions of the Mo-d, Se-p, and O-p orbitals. Optical property analysis reveals that the conductivity and peak value of the pure MoSe2 system are gradually red-shifted toward the low-energy region with the increase of shear deformation. The dielectric function of the O-doped MoSe2 system is red-shifted in the region of 6~10% shear deformation, and the degree of red-shift rises with deformation amount. The findings demonstrate that the electrical structure and optical characteristics of the O-doped MoSe2 system may be modulated effectively by shear deformation, providing a theoretical foundation for expanding the usage of MoSe2 materials in the field of optoelectronic devices. Methods: This study is founded on the CASTEP module in the Materials-Studio software within the first-principles of the density-functional theory framework. The photoelectric properties of the intrinsic and doped systems under shear deformation are calculated using the Perdew-Burke-Ernzerh (PBE) of generalized function under the generalized gradient approximation (GGA). The Monkhorst-Pack special K-point sampling method is used in the calculations, and a 5 × 5 × 1 K-point grid is used for the calculations with a plane-wave truncation energy of 400 eV in the optimization of the structure of each model. After geometrical optimization, the energy convergence criterion for each atom is 1 × 10−5 eV/atom, the force convergence criterion is 0.05 eV/Å, and a vacuum layer of 20 Å in the c-direction is set. [ABSTRACT FROM AUTHOR]

Context: Two-dimensional materials are a new and promising research field in materials science. This is mainly attributed to their unique photoelectric and chemical properties. In addition to possessing unique optoelectronic and chemical properties, two-dimensional materials also have important application prospects in the field of field-effect devices. Based on density functional theory, the effects of uniaxial strain and equibiaxial strain on the mechanical properties, electronic structure, and optical properties of monolayer h-BN were studied using first principles. The results indicate that compressive strain has a significant impact on the stability of monolayer h-BN. The band gap width of monolayer h-BN decreases with increasing strain, and the optical properties of monolayer h-BN exhibit a relative trend under tensile and compressive strains. The influence of biaxial strain on the mechanical properties, electronic structure, and optical properties of monolayer h-BN is greater than that of uniaxial strain. Methods: All the calculations were done by the VASP software based on density functional theory. The interaction between atomic nuclei and electrons is described by the projected added wave pseudopotential (PAW), using the generalized gradient approximation (GGA) to exchange the Perdew-Burke-Ernzerhof (PBE) of the functional. To avoid interlayer interactions, a 15-Å vacuum layer was set up. The Brillouin zone selects the Monkhorst–Pack method to generate 9 × 9 × 1 of k-point grid, the cut off energy is set to 500 eV, the energy convergence standard of the system is 1 × 10−5 eV, and the interaction force between atoms is 0.01 eV/Å. [ABSTRACT FROM AUTHOR]

Organic solar cells (OSCs) are widely studied for their advantages such as simple production, low cost, good flexibility, and large‐area printing. The buffer layer between electrodes and the photoactive layer has a significant impact on the efficiency and stability of OSCs. In order to lower the energy barrier height at the interface, provide an Ohmic contact with lower series resistance, and increase the charge collection efficiency of the corresponding electrodes for either holes or electrons, suitable electrode buffer materials can be chosen. The selection of electrode buffer layer has an important effect on the photoelectric conversion efficiency. Therefore, the study of buffer layer characteristics has certain guiding significance for the improvement of device structure and performance optimization. At present, the buffer layer materials used in OSCs are mainly organic polymer materials, organic small molecule materials, metal fluoride, metal oxides, and so on. Herein, the structure and working principle of OSCs are introduced first. Then, the properties and function of buffer layer in OSCs are summarized and discussed. Finally, the application of common buffer layer materials in OSCs is summarized, and how to improve the performance of the device is described. [ABSTRACT FROM AUTHOR]

A series of CeO2/CdS photocatalysts were prepared by simple solvothermal and auxiliary calcination using cerium nitrate as the precursor. Two different forms of CeO2 (nanosheets (NF-CeO2) and nanorods (NR-CeO2)) were successfully prepared and used to degrade rhodamine B (RhB) to study the photocatalytic activity of the composites. On this basis, the effects of composite proportion and preparation technology on the photocatalytic activity of the composites were studied. The morphology, structure, photoelectric properties and chemical composition of the composites were analyzed. Compared with single photocatalysts (NR-CeO2 and CdS), the NF-CeO2/CdS and NR-CeO2/CdS composite catalyst have stronger photocatalytic performance. In addition, capture experiments and ESR showed that both ∙ O 2 - and h+ impacted on the RhB degradation. After four repeated cycles, NR-CeO2/CdS (1:6) showed stable RhB degradation activity. In the aspect of catalyst interface design, this work not only provides an effective method for the preparation of catalysts with high photodegradation rate and good reuse, but also provides a feasible idea for further research on the degradation of emerging pollutants by photocatalysts. [ABSTRACT FROM AUTHOR]

The study of the photoelectric effect should be introduced at pre-university levels in several countries. Teaching quantum phenomena is neither easy nor intuitive and its difficulty is related to the way the brain learns and creates new patterns. This article proposes a first approach to the phenomenon, starting from a movie scene and the Socratic class, thus offering a didactic tool to apply to pre-university students. In this pre-post study it is shown that there is a remarcable improvement (p < 0.00) in the students comprehension of this effect. [ABSTRACT FROM AUTHOR]

The Solar Panel Modeling Project challenged 10th-grade chemistry students to apply knowledge of Atomic Models to explain electricity generation in a solar panel, deepening their scientific literacy about climate solutions. Here, I describe the project's implementation and outcomes, including the solar panel model template, the 9-day learning sequence, and the evolution of student thinking captured in the summarizing whole-class model. Throughout the unit, students alternated between investigating new chemistry concepts and iteratively refining models, exercising their NGSS sense-making skills. Content learning focused primarily on Atomic Models and the Octet Rule, but also included brief introductions to Lattice Stability and the Photoelectric Effect. The real-world context of the project showed students the practical utility of the otherwise esoteric skill of mapping electron locations and movements between elements. By the project's end, students could verbalize how the specific structure of Silicon, Boron, and Phosphorus in a solar panel results in electron movement and electricity. These students now face the upcoming decades of climate solutions debates armed with deeper scientific literacy about the readiness of this technology for widespread implementation. [ABSTRACT FROM AUTHOR]

Among the practical applications of Quantum Physics, photoluminescence has stood out in different contexts in Engineering and Architecture. Due to the photoelectric effect, certain substances emit photons after being exposed to solar energy. In research in Mexico and Europe, these substances were applied to obtain a photoluminescent effect on bicycle paths. The objective of the research is to investigate the behavior of polymeric residues with the luminescent effect of rare-earth materials in the production of concrete artifacts to illuminate pedestrian and cyclist paths. The concrete blocks were produced with the addition of polymeric recycling waste and luminescent materials, exposed to solar radiation, and tested for mechanical strength. The results of the experiments showed that the polymer residue in concrete significantly increases photon emission, especially when it is processed by extrusion. Although the mixture of photoluminescent materials and polymers reduces the strength of concrete, it still met research objectives for a product meant to illuminate pedestrian and cyclist paths. [ABSTRACT FROM AUTHOR]