Narrow Energy Band Research Articles

Synergistic advancements in battery-grade energy storage: Nb2C/MoTe2(PANI) hybrid electrode material as a enhanced electrocatalyst for hydrogen reduction reaction

The inherent stratified arrangement, narrow energy band gap, and similar electrical conductivity of two-dimensional (2D) molybdenum ditelluride (MoTe2) have attracted considerable interest for their use in supercapacitors. Integrating Niobium Carbide (Nb2C) into the MXene framework significantly improves self-aggregation and electrochemical activity. The current work, Nb2C/MoTe2 was synthesized via a cost-effective and simple hydrothermal technique. However, the Nb2C/MoTe2 nanocomposite shows pronounced self-stacking problems during electrode fabrication, which can significantly restrict the capacity for storing charge. PANI was incorporated as a dopant to address these challenges and enhance electrochemical activity, such as Nb2C/MoTe2(PANI). The performance of supercapacitors was assessed by electrochemical measurement in an aqueous electrolytic solution with a concentration of 2 M potassium hydroxide (KOH). Based on the GCD profile, the Nb2C/MoTe2(PANI) material demonstrates a notable specific capacity (Qs) of 270 C/g, energy density of 72.2 Wh/kg, and power density of 935 W/kg at a current density of 2 A g-1. In contrast, the composite material demonstrates a specific capacity of 185 C/g, as proven by CV conducted at 5 mV/s. In addition, the nanohybrid has a high level of capacitance retention of 87.6 % after undergoing 8500 consecutive cycles. The exceptional efficiency of supercapacitor applications can be ascribed to the enhanced mechanical flexibility, active cooperation, and synergistic impacts of Nb2C/MoTe2 and PANI. The Nb2C/MoTe2(PANI) nanocomposite possesses significant potential for eco-friendly energy generation and allows for a simple single-step fabrication procedure. Consequently, it can serve as an electrode for highly efficient supercapacitors.

First principles study of BN triphenylene-graphdiyne monolayer and bilayer structures with varying C-chain lengths: insights into optical behavior

First-principles calculations engaging density functional theory (DFT) are employed to systematically study the optical characteristics of monolayer and bilayer boron nitride (BN) triphenylene-graphdiyne (Tp-BNyne) structures featuring varying lengths of C-chains. The thermal stability of Tp-BNyne structures at temperatures up to 1000 K is verified. The weak van der Waals interactions due to the small binding energies and significant interlayer distances maintain the cohesion between the layers. The investigation revealed that all Tp-BNyne structures under examination exhibit semiconductor behavior with a band gap in the range of 0.97–2.74 eV. The bilayer configurations demonstrated a narrower energy band gap in comparison to the monolayer ones. Increasing the length of C-chains leads to a reduction in the energy band gap. Delving into the optical behavior of Tp-BNyne structures under photon incidence with parallel and perpendicular polarizations, a distinct anisotropy in the optical characteristics of Tp-BNyne is revealed. The static dielectric constant increases and the optical band gap decreases with increasing C-chain length. The absorption coefficients of monolayer and bilayer Tp-BNyne structures, on the order of 107/m, demonstrate that these sheets can effectively absorb light in the visible and ultraviolet regions. These findings present Tp-BNyne sheets as promising candidates for use in photovoltaic devices to convert sunlight into electrical current, as well as for designing optical devices for ultraviolet protection. Additionally, Tp-BNyne structures are transparent materials, especially in the high-energy range.

ZnIn2S4-based heterostructured photocatalysts for CO2 reduction: A mini review

Abstract ZnIn2S4 (ZIS)’s superior photocatalytic CO2 reduction efficacy, coupled with its distinct layered architecture and narrow energy band profile, makes it an intriguing target for CO2 conversion studies. This article evaluates the photogenerated charge transfer mechanism and photocatalytic CO2 reduction (PCR) efficacy of varied ZIS-based heterostructure catalysts. ZIS-based heterojunctions are initially classified, ensuing discourse on advanced engineering techniques enhancing heterojunction phot catalysts’ PCR functionality like co-catalyst incorporation and morphologic manipulation. The concluding section provides an overview of the present study state and future progression in regard to ZIS-based heterostructured photocatalysts for PCR.

Exploring the physical properties of novel double perovskites A2InAsO6 (A=Sr, Ba) for renewable energy applications: Ab-initio calculations

Nowadays, double perovskites for renewable energy are emerging materials because of their interesting properties such as simple and stable crystal structure. In our study, we theoretically explored the optoelectronic along with mechanical and thermoelectric characteristics of A2InAsO6 (A = Sr, Ba) using density functional theory and semi-classical Boltzmann theory followed by WIEN2k code. The thermodynamic and structural stabilities are determined based on the cohesive energy, enthalpy of formation and tolerance factor. The ductile and brittle behaviour has been checked by Pugh's ratios. The measured values of narrow direct energy band gaps are 0.70 eV for Sr2InAsO6, and 0.18 eV for Ba2InAsO6 with TB-mBJ approximation. These compositions are potentially used in optoelectronic applications because their electronic characteristics are tuneable. In the energy range 0–12 eV, the compositions under consideration exhibit a single-peaked response while the replacement of cation Sr with Ba caused a shift in optical structures towards lower energies. These compositions are also suitable for thermoelectric systems as they possess high values of the figure of merits at room temperature and the measured values 0.049 eV for Sr2InAsO6, and 0.10 eV for Ba2InSbO6 are recorded.

EROSITA narrowband maps at the energies of soft X-ray emission lines

Hot plasma plays a crucial role in regulating the baryon cycle within the Milky Way, flowing from the energetic sources in the Galactic center and plane, to the corona and the halo. This hot plasma represents an important fraction of the Galactic baryons, plays a key role in galactic outflows and is an important ingredient in galaxy evolution models. Taking advantage of the Spectrum-Roentgen-Gamma (SRG first all-sky survey (eRASS1), in this work our aim is to provide a panoramic view of the hot circumgalactic medium (CGM) of the Milky Way. Compared to the previous all-sky X-ray survey performed by ROSAT, the improved energy resolution of enabled us to map, for the first time, the sky within the narrow energy bands characteristic of soft X-ray emission lines. These lines provide essential information on the physical properties of the hot plasma. Here we present the eRASS1\ half sky maps in narrow energy bands corresponding to the most prominent soft X-ray lines and which allowed us to constrain the distribution of the hot plasma within and surrounding the Milky Way. We corrected the maps by removing the expected contribution associated with the cosmic X-ray background, the time-variable solar wind charge exchange, and the local hot bubble. We applied corrections to mitigate the effect of absorption, therefore highlighting the emission from the CGM of the Milky Way. We used the line ratio of the oxygen lines as a proxy to constrain the temperature of the warm-hot CGM, and we defined a pseudo-temperature $ T $ map. The map highlights how different regions are dominated by different thermal components. Toward the outer halo, the temperature distribution of the CGM on angular scales of 2--20 deg is consistent with being constant $ T T 4<!PCT!>$ with a marginal detection of $ T T = 2.7 <!PCT!> 0.2<!PCT!>$ (statistical) $ 0.6<!PCT!>$ (systematic) in the southern hemisphere. Instead significant variations of $ 12<!PCT!>$ are observed on scales of many tens of degrees when comparing the northern and southern hemispheres. The pseudo-temperature map shows significant variations across the borders of the bubbles, suggesting temperature variations, possibly linked to shocks, between the interior of the Galactic outflow and the unperturbed CGM. In particular, a shell characterized by a lower line ratio appears close to the edge of the bubbles.

Advanced Nix/MoSx/MOF-2@g-C3N4 carbon nanostructures for the effective eradication of the Methylene blue dye

In this research, we investigated different hybrid photocatalysts: Ni/Mo.S2/MOF-2@g-C3N4, Mo.S2/MOF-2@g-C3N4, Ni.S2/MOF-2@g-C3N4 and Ni/Mo.S2/MOF-2. These photocatalysts were synthesized using a solvothermal method by incorporating Ni.x/Mo.Sx, the heterojunction showed improved separation of photoinduced charges due to disparity in charge transfer. This resulted in a narrower energy band gap and excellent catalytic activity in photodegradation. The Ni/Mo.S2/MOF-2@g-C3N4 heterostructure demonstrated outstanding photocatalytic efficiency, with up to 91% degradation of methylene blue (MB). This significant degradation was driven by the generation of superoxide (O2 •) and hydroxyl (•OH) radicals. The process adhered to pseudo-first-order kinetics and was effectively completed within 90 min of light exposure. Remarkably, the Ni/Mo.S2/MOF-2@g-C3N4 heterostructure displayed excellent stability, with only minimal performance degradation observed after five consecutive cycles. These results underscore the superior stability of the heterostructure. In summary, our research confirms that the Ni/Mo.S2/MOF-2@g-C3N4 heterojunction photocatalyst is a highly efficient material for the effective removal of methylene blue dye.

Fabrication of hierarchical BiOBr with oxygen vacancies for photocatalytic degradation assisted by SDS additive

Photodegradation is a significant approach to protecting the environment. The BiOBr has attracted great interest due to its unique layered structure and narrow energy band. Herein, the hierarchical BiOBr with oxygen vacancy is fabricated via a facial solvothermal method using the Sodium dodecyl sulfate (SDS) additive. The concentration of oxygen vacancies improves with the increase of SDS content, which could enhance the band gap and the redox ability of BiOBr. The hierarchical BiOBr modified by SDS presents excellent photodegradation activity for RhB and MO under visible light due to the synergistic effect of the oxygen vacancies, the redox ability, porous structure, the separation of photoinduced electron-hole pairs, and light absorption capacity. Furthermore, the BiOBr0.70 presented outstanding photodegradation ability under natural solar light, suggesting the photocatalysts could meet certain practical applications.

GaSb/Si Heterojunction Based Pocket Engineered Vertical Non-Uniform Channel Double Gate TFETs for Low Power Applications

This article compares the performance of two Vertical Non-Uniform Channel Double Gate Tunnel Field Effect Transistors (VNUCDGTFETs), a normal all-Silicon Tunnel Field-Effect Transistor (TFET) having a pocket and another one a Gallium Antimonide/Silicon heterojunction TFET with pocket. GaSb is a III-V narrow energy band gap material, employed in the source area of the TFET structure to decrease the tunneling width and thus to make more number of carriers capable enough to tunnel through the heterojunction. The proposed source pocket heterojunction non uniform channel TFET presents superior performance as compared to the conventional non uniform channel vertical TFET with a pocket, regarding a larger ION/IOFF ratio, a reduced sub-threshold swing, and a smaller threshold voltage at VDS = 0.5 V. Furthermore, the proposed TFET device undergoes a comprehensive analysis of both DC parameters and various analog/RF parameters.

Azadirachta indica leaf extract-derived NiS@Functionalized biochar catalyst: Efficient acetalization and enhanced reusability in photodegradation of tinidazole

Growing biodiesel production creates a significant volume of glycerol (Gly), a by-product that must be transformed into valuable compounds by developing novel and sustainable technologies. Solketal is one of several valuable compounds derived from residual Gly released during biodiesel synthesis. A green synthetic process followed by the co-precipitation method was used to fabricate NiS@Functionalized Biochar (NBS) using Azadrichta indica leaf extract. The nanocatalyst was extremely active for microwave-assisted solketal synthesis from Gly and acetone. A 99.7 ± 0.3 % conversion of Gly with 100 % solketal selectivity occurred under the optimum reaction conditions (catalyst loading 4 wt%, Gly to acetone molar ratio 1: 5, reaction time 6 min, and temperature 65 °C). The suggested reaction mechanism demonstrates the selective synthesis of solketal. The NBS catalyst showed excellent reusability up to six cycles, and after that, it was used for the photodegradation of tinidazole, where 89.14 % degradation efficiency was obtained within 110 min of sunlight irradiation. A narrow energy band gap (1.99 eV) and effective charge separation favor the photocatalytic activity of the reused catalyst. The environmental friendliness of the catalyst for the solketal synthesis process was examined by studying green metrics.

CdS@NiCr-LDH Z-scheme heterojunction with high adsorption–photocatalysis for uranium(VI) removal without any sacrificial agent

The use of photocatalysis for the removal of U(VI) has the advantages of being green, eco-friendly and sustainable. It is common practice to enhance the photocatalytic activity of photocatalysts by adding sacrificial agents, however, this is uneconomical and contrary to the vision of carbon neutrality and carbon peak in the world. Herein, we fabricate a Z-scheme heterojunction for the photocatalytic removal of uranium (VI) based on CdS nanorods@NiCr layered double hydroxide (CdS@NiCr-LDH). Excellent photocatalytic efficiencies and removals were achieved under visible light irradiation without any sacrificial agent. The optimum uranium(VI) removal rate of CdS@NiCr-LDH was 0.057 min‐1, which was 6.3 and 5.0 times higher than that of CdS and NiCr-LDH, respectively. In particular, the U(VI) removal amount over CdS@NiCr-LDH reached 2246.14 mg g−1. The CdS@NiCr-LDH heterojunction creates a narrower energy band gap (Eg = 2.06 eV), which is more favorable for visible light absorption, according to UV–vis DRS results. According to ESR and DFT calculations, possesses an intrinsic electric field between NiCr-LDH and CdS composite that efficiently prevents electron-hole complexation, resulting in highly efficient removal of U(VI) under visible light irradiation without the need of sacrificial agents. This work lays the foundation for research on photocatalytic U(VI) treatment by CdS@NiCr-LDH in wastewater.

Modified successive ionic layer adsorption and reaction for interconnected bismuth vanadate nanograins: Highly active visible light harvesting photoanodes

A modified successive ionic layer adsorption and reaction (SILAR) method is developed for depositing interconnected bismuth vanadate (BiVO4) nanoparticles with improved visible light harvesting activity. Facile control of preparative parameters like deposition cycles, anionic precursor, pH and deposition temperature significantly altered BiVO4 surface morphology. BiVO4 thin films prepared with Na3VO4 anionic precursor show dispersed nanoparticles type morphology and that deposited with NaVO3 precursor displays 3D interconnected nanoparticles morphology. The BiVO4 photoanodes with 3D interconnected nanoparticles morphology exhibits an excellent photocurrent density of 5.19 mA cm−2 at 1.23 V vs. RHE with superior photostability and improved applied bias photon to current efficiency (ABPE) (1.50 %) compared to dispersed nanostructured BiVO4 photoanodes. The excellent photoelectrochemical (PEC) characteristics of BiVO4 photoanodes with 3D interconnected nanoparticle morphology can be ascribed to porous morphology, optimum thickness, narrow band gap energy and favorable electronic band structure for water splitting. The current study illustrates the usefulness of the modified SILAR approach for depositing 3D interconnected BiVO4 nanoparticle morphology in a single step that is superior and efficient to previously reported multistep processes.

Interlayer Polymerization to Construct a Fully Conjugated Covalent Organic Framework as a Metal-Free Oxygen Reduction Reaction Catalyst for Anion Exchange Membrane Fuel Cells.

Two-dimensional (2D) covalent organic frameworks (COFs) have a multilayer skeleton with a periodic π-conjugated molecular array, which can facilitate charge carrier transport within a COF layer. However, the lack of an effective charge carrier transmission pathway between 2D COF layers greatly limits their applications in electrocatalysis. Herein, by employing a side-chain polymerization strategy to form polythiophene along the nanochannels, a conjugated bridge is constructed between the COF layers. The as-synthesized fully conjugated COF (PTh-COF) exhibits high oxygen reduction reaction (ORR) activity with narrowed energy band gaps. Correspondingly, PTh-COF is tested as a metal-free cathode catalyst for anion exchange membrane fuel cells (AEMFCs) which showed a maximum power density of 176mWcm-2 under a current density of 533mAcm-2. The density functional theory (DFT) calculation reveals that interlayer conjugated polythiophene optimizes the electron cloud distribution, which therefore enhances the ORR performance. This work not only provides new insight into the construction of a fully conjugated covalent organic framework but also promotes the development of new metal-free ORR catalysts.

Sulfur and chloride co-doped g-C3N4 in photocatalytic peroxymonosulfate activation for enhanced acetaminophen removal: Combination of experiments and DFT calculations

As a green photocatalyst with simple synthesis method, excellent electronic structure, and metal-free properties, the deficiencies of pristine graphitic carbon nitride, such as high electron transfer resistance and narrow energy band gap, inhibit its photocatalytic activity to some extent. In this paper, we synthesized a sulfur and chlorine co-doped g-C3N4 (SCl-CN) capable of efficient photocatalytic activation of peroxymonosulfate (PMS) by calcining a mixture of ammonium chloride and thiourea. By means of DFT calculation, the contribution of sulfur and chlorine to photogenic electron hole separation was discussed. The electrostatic potential of SCl-CN and the adsorption model between SCl-CN and PMS were deduced, and the activation mechanism of PMS was further analyzed. According to the calculated results, the incorporation of sulfur and chlorine tuned the electronic configuration of the material and intensified the interactions between SCl-CN and PMS. It is shown that free and non-free radicals act simultaneously in the SCl-CN/PMS/Vis system. This study provides a new idea for the study of photocatalytic activation of PMS by non-metallic co-doped carbon nitride.

Alleviation of the on-state dynamic conductance decline in a GaN high electron mobility transistor with heavy carbon doping

Carbon doping is a standard blocking-voltage-enhancing technique for commercial silicon substrate-based AlGaN/GaN power switching transistors, although the incorporation of carbon into GaN may deteriorate the dynamic on-state resistance (dy-R on) properties of the device. Commonly, researchers have believed that the greater the carbon doping, the greater the deterioration in dy-R on. Surprisingly, in this work, the opposite was observed: the dy-R on value decreased as the carbon concentration increased, particularly when the density exceeded several 1017 cm−3. This phenomenon is explained by the effect of electric field-induced band-to-band electron tunneling into the two-dimensional electron gas (2DEG) conduction channel, originating from the ionization of acceptor-like nitrogen site carbon atoms (CN) in the device off-state with large drain bias. Simulation data indicated that negatively ionized CN may generate a much larger electric field in samples with higher carbon doping, which may induce a narrower 2DEG back energy band barrier that increases the possibility of electron band-to-band tunneling.

Elastic anisotropy, mechanical, lattice dynamics, and electronic properties of MPdZ (M = Hf, Zr, Ti; Z = Sn, Ge, Si). DFT study

Elastic anisotropy, mechanical, lattice dynamics, and electronic properties of MPdZ (M = Hf, Zr, Ti; Z = Sn, Ge, Si) compounds have all been computed from first principles. All compounds are ductile according to Pugh’s ratio, Cauchy’s pressure, and Poisson’s ratio values. Based on the Born stability criteria, each MPdZ compound is mechanically stable. The high machinability index values of TiPdSn and ZrPdSi indicate their high quality of machinability. The hardness of the compounds is between 5.5 and 8.0 GPa, and the highest hardness is found in the HfPdSn (7.966 GPa) compound. The computed Kleinman parameter indicates that the bond stretching for all MPdZ compounds is minimal. The anisotropy indices incorporating graphical presentation indicate all MPdZ compounds are anisotropic. Young’s modulus elastic anisotropy is less compared to the Zener anisotropy index, equivalent Zener anisotropy measure, and anisotropy ratio of the maximum and minimum shear moduli. Prominent anisotropy for sound velocities is observed in HfPdSi, ZrPdSi, and TiPdSi compounds. With the exception of TiPdGe, other compounds in this work are dynamically stable due to the lack of imaginary phonon modes. HfPdSn, ZrPdSn, and TiPdSn have narrow energy band gaps among the compounds that were studied.

Fabrication of ZnO Scaffolded CdS Nanostructured Photoanodes with Enhanced Photoelectrochemical Water Splitting Activity under Visible Light.

CdS, characterized by its comparatively narrow energy band gap (∼2.4 eV), is an appropriate material for prospective use as a photoanode in photoelectrochemical water splitting. Regrettably, it encounters several obstacles for practical and large-scale applications, including issues such as bulk carrier recombination and diminished conductivity. Here, we have tried to address these challenges by fabricating a novel photoelectrode (ZnO/CdS) composed of one-dimensional ZnO nanorods (NRs) decorated with two-dimensional CdS nanosheets (NSs). A facile two-step chemical method comprising electrodeposition along with chemical bath deposition is employed to synthesize the ZnO NRs, CdS NSs, and ZnO/CdS nanostructures. The prepared nanostructures have been investigated by UV-visible absorption spectroscopy, X-ray diffraction, Raman spectroscopy, transmission electron microscopy (TEM), and scanning electron microscopy. The fabricated ZnO/CdS nanostructures have shown enhanced photoelectrochemical properties due to the improvement of the semiconductor junction surface area and thereby enhanced visible light absorption. The incorporation of CdS NSs has been further found to promote the rate of the charge separation and transfer process. Subsequently, the fabricated ZnO/CdS photoelectrodes achieved a photocurrent conversion efficiency 3 times higher than that of a planar ZnO NR photoanode and showed excellent performance under visible light irradiation. The highest applied bias photon-to-current conversion efficiency (% ABPE) of about ∼0.63% has been obtained for the sample with thicker CdS NSs on ZnO NRs with a photocurrent density of ∼1.87 mA/cm2 under AM 1.5 G illumination. The newly synthesized nanostructures further demonstrate that the full photovoltaic capacity of nanomaterials is yet to be exhausted.

Enhanced structural, optical and electrical properties of polycrystalline WO3 thin films achieved by aluminum nanosheets coating

Herein the effects of aluminum nanosheets on the structural, morphological, optical and electrical properties of tungsten oxide thin films are reported. Polycrystalline phase of the thermally evaporated WO3 was achieved by the pulsed laser welding technique. The polycrystalline films are then coated with Al nanosheets of thicknesses of 100 nm and 150 nm by the ion coating technique. It is observed that Al induces the domination of the hexagonal structure of WO3 over the tetragonal. Associated with the enhanced crystallinity the light absorption in the films increased by more than 60% and the energy band gap narrowed significantly. Namely the energy band gap of the as grown WO3 decreased from 3.15 eV to 2.85 eV and 2.59 eV as the Al layer thickness increased from 100 to 150 nm, respectively. It is also observed that crystalline films of WO3 exhibited lower electrical resistivity compared to films fabricated by other techniques. The temperature dependent electrical resistivity measurement was carried out in the temperature range of 310–420 K. It showed room temperature values of 2.5 ( Ω cm), 2.2 ( Ω cm) and 1.9 ( Ω cm) and impurity levels centered at 0.25 eV, 0.34 eV and 0.16 eV for uncoated and films coated with Al nanosheets of thicknesses of 100 nm and 150 nm, respectively. The enhanced crystallinity that is accompanied with narrower energy band gap and lower electrical resistivity values make crystalline WO3 films promising for optoelectronic applications.

Study of dielectric and electrical properties of novel lead-free double perovskite oxide

The current work focuses on the synthesis of lead free novel double perovskite oxide and detailed investigation of its dielectric and electrical characteristics. Single phase lead free double perovskite Pr2FeCrO6 (PFCO) is prepared by co-precipitation technique. Structural studies reveal orthorhombic structure with Pbnm space group. Scanning electron microscopic study shows mixed type of grains; spherical and rectangular grains forming layered structures with few pores. Bonding features and local structure are analyzed via FTIR and Raman spectroscopy. Optical absorption study show narrow energy band gap of 2.14 eV. Room temperature dielectric studies show colossal dielectric constant (∼104) with low loss. The dielectric relaxation dynamics are studied in the temperature range; 25° to 200 °C. The detailed investigation of electrical properties and conduction mechanism in PFCO is carried out via impedance spectroscopy.

Probing the Dipole of the Diffuse Gamma-Ray Background

We measured the dipole of the diffuse γ-ray background (DGB), identifying a highly significant time-independent signal coincidental with that of the Pierre Auger UHECR. The DGB dipole is determined from flux maps in narrow energy bands constructed from 13 yr of observations by the Large Area Telescope (LAT) of the Fermi satellite. The γ-ray maps were clipped iteratively of sources and foregrounds similar to that done for the cosmic infrared background. The clipped narrow energy band maps were then assembled into one broad energy map out to the given energy starting at E = 2.74 GeV, where the LAT beam falls below the sky’s pixel resolution. Next we consider cuts in Galactic latitude and longitude to probe residual foreground contaminations from the Galactic plane and center. In the broad energy range 2.74 < E ≤ 115.5 GeV, the measured dipoles are stable with respect to the various Galactic cuts, consistent with an extragalactic origin. The γ-ray sky’s dipole/monopole ratio is much greater than that expected from the DGB clustering component and the Compton–Getting effect origin with reasonable velocities. At ≃(6.5–7)% it is similar to the Pierre Auger UHECRs with E UHECR ≥ 8 EeV, pointing to a common origin of the two dipoles. However, the DGB flux associated with the found DGB dipole reaches parity with that of the UHECR around E UHECR ≤ 1 EeV, perhaps arguing for a non-cascading mechanism if the DGB dipole were to come from the higher-energy UHECRs. The signal-to-noise ratio of the DGB dipole is largest in the 5–30 GeV range, possibly suggesting the γ-photons at these energies are the ones related to cosmic rays.

Poly(vinyl alcohol)-assisted synthesis of 3D Bi2S3 submicrometric structures for feasible chip photodetector applications

Bismuth sulfide (Bi2S3) is a chalcogenide semiconductor with a relatively narrow energy band gap that is promising for use in solar cells and photodetectors.