UV Vis NIR Spectrometer Research Articles

Exploring the anticancer potential of novel chalcone derivatives: Synthesis, characterization, computational analysis, and biological evaluation against breast cancer

This study presents a detailed synthesis and in-depth structural analysis of chalcone compounds with putative anticancer activity. The synthesis procedure for (2E)-1-(2,4-dichlorophenyl)-3-(4-methylphenyl) prop‑2-en-1-one (MLDCL), (2E)-1-(4-fluorophenyl)-3-(4-methylphenyl) prop‑2-en-1-one(MLFC) and (2E)-3-(4-methylphenyl)-1-(4-nitrophenyl) prop‑2-en-1-one (MLNC) involves Claisen-Schmidt condensation reaction. Modern analytical methods like FT-IR and H1 NMR spectroscopy were performed for structural characterization and accurate determination of chalcone compounds in the study. Using a UV–Vis-NIR spectrometer, the linear absorption spectra of three crystals were determined. The optical band gap (Eg) value of these chalcones is acquired from the tauc's plot of (αhv)2/3 against (hv). The in silico molecular docking with protein 3EQM provided valuable insights into potential interactions with the created compounds, yielding docking scores ranging from -8.8 to -7.8. Specific amino acid residues, such as ALA438, ALA306, and ILE133, were implicated in these interactions. The top-ranked compound MLNC (TOP1) from docking was further deemed for molecular dynamics studies, MTT assay, apoptosis, and cell cycle studies. The structural dynamics and stability of protein complexes 3EQM-APO, 3EQM-ASD (standard), and 3EQM-TOP1 were assessed over a 300 ns simulation period. Molecular dynamics studies showed that the complex was stable for a complete 300 ns. MTT assay was performed on triple-negative breast cancer cell line MDMAB-231 and normal fibroblast L929 cell line. An apoptosis and cell cycle studies were performed to further confirm the anti-cancer activity of the top-ranked compound MLNC.

Influence of choline chloride pH adjuster on physical and optical properties of CuInSe2 thin films by CBD

We concentrate on low-cost thin film solar cells with the help of choline chloride acting as a pH adjuster because copper ternary material compounds and their alloys have become more and more lavish over the past 20 years. Chemical Bath Deposition (CBD) is used to produce copper indium selenium (CuInSe2) thin films on glass substrates while a pH adjuster is present. The micro structural and elemental properties are studied using X-ray diffraction (XRD), Raman, Scanning Electron Microscope (SEM), and Energy Dispersive Spectroscopy (EDS). The optical studies of CuInSe2 thin films are done using a UV–Vis–NIR spectrometer. XRD and Raman spectra shows that the CIS thin films deposited in the sequence of Glass/In/Se/Cu2Se/Se (labeled as CISB) and annealed at 400 °C (CISB400) contains all the peaks corresponding to the chalcopyrite CuInSe2. From the EDS measurements it was noted that the selenium to metal ratio (Se/Cu + In) for all the samples changes with temperature. It is worth to note that the film thickness decreases with a decrease in the pH of choline chloride which results a change in the optical band gap of the films. The optical properties of these thin films are greatly influenced by adjusting pH and it gives better results for optoelectronic devices with a sustainable UV filter which absorbs more in ultraviolet vicinity. The energy gap (Eg) values of the CISB samples were determined and is found to be suitable for photovoltaic conversion process.

Optimizing the performance of (Sb0.2Sn0.8)0.5(S0.9Se0.1)0.5 crystal-based self-powered photodetectors

The need to develop electronic systems capable of functioning without an external power source is an utmost priority, especially in the pursuit of self-powered photodetection. Through the direct vapor transport (DVT) method, we have synthesized a single crystal of the quaternary compound (Sb0.2Sn0.8)0.5(S0.9Se0.1)0.5 for self-driven photodetectors. The crystal's elemental composition was ascertained via energy-dispersive X-ray analysis (EDX), along with Field emission scanning electron microscopy (FESEM) provided insight into its surface morphology. The orthorhombic crystal system of the grown sample has been validated by a powder X-ray diffractometer (XRD). The regular spot pattern of SAED and the well-defined sharp peaks observed in the XRD graph collectively indicate the crystal's pronounced crystalline quality. The lattice parameters closely resemble the reported data. A UV–VIS-NIR spectrometer was utilized to deduce a direct optical band gap of 1.49 eV. Raman spectroscopy was used to examine different phonon modes. We analyzed its pulsed photo response by subjecting the grown crystal to different wavelengths and varying intensities of white light at self-biased mode and by applying 1 V bias. Our analysis enabled us to determine favourable photodetection parameters.

An experimental and computational study for enhancement in optical nonlinearity and dielectric behaviour in thermal annealing induced Ag diffusion at Ag/Sb-S-Se interface

The annealing induced Ag diffusion into Sb40Se30S30 film brings enormous changes in its linear-nonlinear optical along with the structural and dielectric properties which is reported in the current study. The prepared Ag/Sb40Se30S30 film was annealed at different temperatures like 100,150,200 and 250 °C. The structure remained amorphous one as confirmed from XRD while the particle size increased with annealing as observed from FESEM images. The Raman study depicts the microstructural change in terms of shift in vibrational peaks. The optical study was done by UV–Vis-NIR spectrometer from which different optical parameters were evaluated. The decrease in optical bandgap with increase in linear refractive index is accompanied by the increase in optical density, extinction coefficient and decrease in skin depth. The dielectric loss factor increased while the quality factor decreased with annealing. The static dielectric constant increased with the increase in carrier concentration. Both the electrical as well as optical conductivity are found to be increased while optical electronegativity and plasma frequency decreased with annealing. The 3rdorder nonlinear susceptibility and non-linear refractive index are doubled with annealing while there is decrease in nonlinear absorption coefficient. The surface wettability study infers the hydrophilic nature sustains with annealing. The computational analysis using the DFT method was carried out to provide some necessary information about the structure and physical properties of the prepared materials.

Synthesis, crystal growth, thermal, density functional theory, linear and nonlinear optical properties of 3-Aminopyridinium-2‑chloro-4-nitrobenzoate single crystal

In the present work, a 3rd-order nonlinear optical compound 3-Aminopyridinium-2‑chloro-4-nitrobenzoate (3AP2C4N) was successfully synthesised by following the slow-cooling solution growth technology 3AP2C4N single crystals are grown. The crystalline structure, established by single crystal x-ray diffraction investigation, revealed that 3AP2C4N belong to the triclinic system with the centro-symmetric space group of P-1. Powder x-ray diffraction measurement results support the formation of crystalline phase. The Fourier transform infrared analysis revealed the existence of different functional groups establishing the formation of 3AP2C4N molecule. Adopting the UV–Vis-NIR spectrometer, the absorption coefficient was measured and the calculated bandgap for 3AP2C4N was 3.25 eV. The luminescence properties of the title compound, which was excited at 320 nm, were studied using photoluminescence spectroscopy. TG-DTA measurements were used to investigate the thermal behaviour of 3AP2C4N. From the Z-scan approach it is evident that 3AP2C4N crystals are much suitable for optical limiting applications. DFT simulations at the B3LYP / 6–311++G (d, p) level enabled to evaluate the molecule's HOMO-LUMO, molecular electrostatic potential and contour map. The Hirshfeld surface investigations showed the presence of intermolecular interactions in the molecule.

The size effect on the optical-electrical properties of Cu2S/CdS thin film towards the performance on Ag/p-Cu2S/n-CdS/ATO heterojunction diode

Here we report, room temperature deposition of Cu2S/CdS thin film on antimony doped tin oxide(ATO) substrate through spray pyrolysis and dip coating technique. The effect of size on the deposited Cu2S/CdS thin films and its heterojunction parameters are extensively investigated. The sizes of the thin film are estimated through field-emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) images. The optical properties of the Cu2S/CdS thin film are studied using UV–Vis–NIR spectrometer. It is found that increase in the size, the transmittance decreases, consequently the band-gap energy decreases from 2.92eV to 2.86eV. The refractive index and the dielectric constant are calculated from the optical measurements. In addition, the dispersion of the refractive index is discussed in terms of the Wemple-DiDomenico single-oscillator model. The oscillator parameters such as optical dispersion energies, dielectric constant, the average value of oscillator strength, wavelength of single oscillator, plasma frequency and lattice energy are evaluated. To examine the size-dependent electrical parameters of Cu2S/CdS thin film, high-quality vacuum evaporated silver (Ag) is used as front contact. The current-voltage (I–V) curves of the Ag/p-Cu2S/n-CdS/ATO/glass heterojunction device are measured under dark mode at standard testing conditions (STC). The dark measurements of the fabricated device are investigated through the conventional I–V method, Norde method, and Cheung method. It is observed that the potential height of the heterojunction device decreases from 0.89 to 0.76 with an increment of the size of Cu2S/CdS thin films. It is observed that the size strongly influenced the diode parameters viz. ideality factor, saturation current, barrier height, series, and shunt resistance performance.

Characterizations of MoS2 nanosphere fabricated using vacuum thermal evaporation at steady and rapid heating

Two-dimensional MoS2 has been speculated to be the best material to replace graphene due to its peculiar structural-electronic properties. The MoS2 with size smaller than its exciton Bohr radius (ca. 1.61 nm) would favor multi exciton generation upon absorption of photon with sufficient energy, Ephoton ≫ Egap (1.89 eV); which would increase the efficiency of an excitonic solar cell greater than 60%. Despite promising properties of the MoS2, however an excitonic solar cell with high efficiency is yet to be exhibited. In this work, the MoS2 thin films were fabricated using vacuum thermal evaporation technique and characterized. Four objectives have been outlined i.e., to study the effect of heating rate (steady, and rapid) on the (i) morphology, (ii) size, (iii) optoelectronic and (iv) crystal properties of the fabricated thin films. The MoS2 precursor was heated at the rate 2.027 A/s (steady), and 18.75 A/s (rapid), 1.5 × 10−3 Torr, 1.48 A, and 4.58 V. The deposited films later were characterized using Field Emission Scanning Electron Microscope with Energy Dispersive X-ray attachment, photoluminescence spectrometer, UV–vis-NIR spectrometer, and X-ray Diffractometer. The fabricated thin films exhibited nanosphere morphology with different size distributions i.e., wide (steady heating), and narrow (rapid heating). Two hypotheses were made based on the optoelectronic properties i.e., the basic building block of the MoS2 thin film fabricated under steady heating is (i) experiencing stronger quantum confinement effect, and (ii) dominated by nanocrystals which are smaller than that of the rapid heating. Similar energy loss could be expected in both MoS2 thin films i.e., ca. 0.15 to 0.17 eV, indicating the existence of shallow trap states. The MoS2 thin films were dominated by (002), (004), and (106) crystal planes. Therefore, the vacuum thermal evaporation technique would offer materials with unique size, crystal arrangement, and optoelectronic properties upon change of heating rate.

Enhanced SHG performance of Cd 2+ doped DAST crystal featuring charge exchange owing metal ion-organic ligand for NLO applications

The slow evaporation solution (SEST) technique was used to grow a CdSO4 (5 %) doped DAST (CdS5-DAST) single crystal. The structural properties of the grown CdS5-DAST single crystal were investigated using single crystal X-ray Diffraction (SXRD) analysis. The SXRD data reveals that the CdS5-DAST crystal is non-centrosymmetric with a monoclinic (Cc) space group. The existence of a metal–organic 5 % of CdSO4 in DAST was affirmed by energy dispersive spectroscopy analysis (EDAX). The optical property of the grown single crystal was investigated by a UV–vis-NIR spectrometer, which showed the absorption cut-off wavelength is 380 nm. As a result, the electronic transition from non-bonding molecular orbital (ground) states to antibonding molecular orbital (excited) states corresponds to the absorption λ maximum. The energy (ΔE) requirement is small enough for electrons to transition from n-π* states. The optical bandgap (Eg), refractive index and extinction coefficient of the CdS5-DAST single crystal are calculated. As a result, crystals have an optical bandgap of 2.1 eV. Cd2+ doped DAST crystal enhances SHG performance significantly, owing to charge exchange facilitated by the metal ion-organic ligand and electron density. The grown CdS5-DAST crystal has a best SHG response and compared to the some organic NLO crystals. The PL spectrofluorometer study substantiates that green emission features at a wavelength of 527 nm. TG-DTA was being used to analyze the thermal characteristics of the crystal was thermally stable up to 259.95 °C.

Structural, dielectric, magnetic, and ferroelectric properties of bismuth ferrite (BiFeO3) synthesized by a solvothermal process using hexamethylenetetramine (HMTA) as precipitating agent

Multiferroic BiFeO3 (BFO) has been synthesized by the solvothermal technique for 4 h at 180 °C using Hexamethylenetetramine (HMTA) as a precipitating agent. Optimizations on HMTA concentration were performed to attain BFO in a narrow possible time using the solvothermal method. The effect of HMTA concentration on structural properties was investigated by XRD, FE-SEM, FT-IR, and Raman techniques. Moreover, the magnetic, ferroelectric, dielectric, and optical properties were studied by VSM, Ferroelectric analyser, Dielectric spectrometer, and UV–Vis–NIR spectrometer, respectively. The XRD data has unveiled the significant role of HMTA, as a precipitating agent, in obtaining the pure phase BFO at a particular concentration. A high concentration of HMTA (6 M) is found to be more favourable for producing pure phase BFO within the short reaction time of 4 h without any impurity phase formations. The FE-SEM images have shown the formation of granular structures that are inhomogeneously distributed throughout the powdered BFO with porosities. In addition, the magnetic measurements confirmed that the BFO synthesized with varying HMTA concentration exhibits a reasonable week ferromagnetic behaviour. However, the pure BFO powder synthesized at 6 M HMTA shows high magnetization value (0.72 emu/g) compared to the other samples synthesized at low concentrations of HMTA. Further, the dielectric measurements of all the synthesized BFO samples have shown a decrease in dielectric loss with an increase in frequency. Whereas the dielectric behaviour exhibited by the pure BFO synthesized at 6 M HMTA has shown a high dielectric constant value with moderate dielectric loss. A ferroelectric analyser studies the ferroelectric behaviour of BFO powder. The study revealed that pure phase BFO synthesized with 6 M HMTA exhibits a high value of remanent polarization with unsaturated P-E loops due to the high leakage current in the sample. The UV–Vis data shows that the BFO samples exhibited an excellent optical absorption in the visible range with narrow optical band gaps. Therefore, all the characterizations related to magnetic, structural, dielectric, ferroelectric, and optical properties of synthesized pure BFO have proven the significance of precipitating agent HMTA in the solvothermal synthesis method. Based on our findings, the synthesized pure phase BFO can be an excellent semiconducting photocatalyst for multiferroic based photocatalysis applications.

Structural, morphology and optical properties of PbS (Lead Sulfide) thin film

We report here the synthesis, structural and optical properties of PbS thin film. The growth rate in the chemical path deposition time was optimized during film deposition. The surface of the PbS film is compact and well covered, with a smooth surface and irregularly shaped spherical grain of random sizes. The electrical studies were measure with the Hall effect and Hot probe for the optimized film and the transmittance and band gap of the films were measure by the UV–VIS–NIR Spectrometer in the range of 400–2500 nm. It was observed that the band gap decreases and thickness increased with the increases in deposition time. The room temperature photoluminescence emission spectra of the as grown PbS thin films. Radiation of wavelength 425 nm was used for excitation.

Study on structural, morphological, optical, and luminescence properties of nickel oxide thin-film synthesized by dip-coating technique

Nickel oxide is one of the best materials for fabricating optical devices. The Dip-coating technique was used to deposit nickel oxide thin films on a glass substrate. Nickel acetate tetrahydrate Ni (Ac) 2·H2O was used as starting precursor and monoethanolamine (MEA) was added as a catalyst. These fabricated films were pre-heated at 150 °C for 10 min and then annealed in the air at 400–700 °C temperatures. XRD, UV–Vis-NIR, FESEM, EDAX, and photoluminescence techniques are used for analyzing the fabricated films. FESEM and EDAX studies confirmed the surface and the elemental analysis of the prepared films. X-ray diffraction studies confirmed the structure of the Nickel oxide film. The UV–Vis-NIR spectrometer was used to analyze the transmission and absorption spectra of the films.

Growth and characterization of thiosemicarbazide barium chloride [Ba(NH2NHCSNH2)Cl2]crystals: Novel potential NLO material

Semiorganic Nonlinear optical Crystals of Thiosemicarbazide Barium Chloride was grown by slow evaporation solution growth technique. The unit cell parameters were estimated by subjecting the crystal to single crystal X- ray diffraction. The Grown crystals were subjected to powder X- ray diffraction for analyzing the crystalline nature of the sample. The transmission spectrum of grown crystal was recorded by UV–Vis–NIR Spectrometer in the range between 200 nm and 800 nm which addressed the high percentage of transmission of the sample in the entire visible region. The presence of functional groups was studied by FT- IR analysis. Thermal Stability and melting temperature of the grown crystal was identified from TG –DTA analysis Dielectric behaviour of the grown crystal was studied and the results are discussed in detail. Second harmonic generation (SHG) conversion efficiency has been estimated as 1.21 times greater than potassium dihydrogen phosphate crystal.

Effect of gamma irradiation on physical, optical, spectroscopic and structural properties of Er3+-doped vitreous zinc borotellurite

In the present report, erbium doped zinc borotellurite glasses were irradiated with 50 kGy gamma radiation using a60Co radioisotope source. The effect of gamma irradiation on the physical, structural, optical and spectroscopic properties of erbium doped zinc borotellurite glasses was studied. Also the shielding properties of the un-irradiated glasses were studied with the help of Phy-X/PSD software. The gamma irradiation caused some structural changes as indicated by FTIR and Raman studies which may be due to the formation of the new structural units. Its influence on the optical properties like band gap (direct and indirect band gap), Urbach energy and refractive index were analyzed with the help of UV–Vis–NIR spectrometer. The UV–Vis–NIR absorption spectra showed increase in absorption after the gamma irradiation. The optical band gap value decreased for the irradiated samples. The spectroscopic properties such as stimulated emission cross-section, bandwidth, lifetime etc. Got marginally modified due to gamma irradiation. The shielding properties of the un-irradiated glasses were improved with the increasing rare earth concentration. The glasses with rare earth doping showed less changes in their properties after gamma irradiation which indicates that these glasses are more resistant to gamma radiation as compared to the base glass.

Effect of vitamin-C on structural, thermal, and optical properties of lithium sulfate monohydrate crystal

A single crystal of vitamin-C-doped lithium sulfate (VCLSM) was grown at room temperature from aqueous solution by slow evaporation method. The as-grown crystals were found to be transparent and yellow in color. Powder X-ray diffractogram of the pure and doped crystals was recorded and various planes were identified for their corresponding reflections. The X-ray diffraction (XRD) analysis validated the crystalline nature of the samples. Single crystal X-ray diffraction study revealed the structure of the crystals and also revealed their monoclinic crystal system with space group P21. The vibrational modes of different functional groups present in the compound were analyzed using Fourier transform infrared (FTIR) spectral analysis. Thermal characteristics study of the crystal was carried out by thermogravimetric analysis (TGA) and differential thermal analysis (DTA) techniques, which clearly showed that the materials have high thermal stability even after doping. Optical transmittance spectrum using UV–Vis–NIR spectrometer showed that the grown crystal is highly transparent in the whole visible and Infrared (IR) region. Second-harmonic generation (SHG) property was confirmed for both pure and doped crystals by Kurtz’s powder test using Nd:YAG Laser.

Impact of Dy2O3 Substitution on the Physical, Structural and Optical Properties of Lithium–Aluminium–Borate Glass System

In this study, a series of Li2O-Al2O3-B2O3 glasses doped with various concentrations of Dy2O3 (where x = 0.0, 0.2, 0.4, 0.6, 0.8, and 1.0 mol%) were prepared by using a conventional melt-quenching technique. The structural, physical and optical properties of the glasses were examined by utilising a variety of techniques instance, X-ray diffraction (XRD), UV–Vis-NIR spectrometer, Fourier transform infrared (FTIR) and photoluminescence (PL). The XRD spectra demonstrate the amorphous phase of all glasses. Furthermore, the UV-vis-NIR spectrometers have registered optical absorption spectra a numbers of peaks which exist at 1703, 1271, 1095, 902, 841, 802, 669, 458, 393 and 352 nm congruous to the transitions from the ground of state (6H15/2) to different excited states, 6H11/2, 6F11/2 + 6H9/2, 6F9/2 + 6H7/2, 6F7/2, 6F5/2, 6F3/2, 4F9/2, 4I15/2, 4F7/2 and 6P7/2, respectively. The spectra of emission exhibit two strong emanation bands at 481 nm and 575 nm in the visible region, which correspond to the transitions 4F9/2 → 6H15/2 and 4F9/2 → 6H13/2. All prepared glass samples doped with Dy2O3 show an increase in the emission intensity with an increase in the concentration of Dy3+. Based on the obtained results, the aforementioned glass samples may have possible applications, such as optical sensor and laser applications.

Synthesis and luminescence properties of Eu3+ doped potassium titano telluroborate (KTTB) glasses for red laser applications

A novel series of europium doped potassium titano telluroborate (Eu3+: KTTB) glasses were prepared with the melt quenching and characterized with XRD, SEM, FTIR, UV–Vis–NIR spectrometer, PL etc. And their bonding parameter (δ), the Judd-Ofelt (J-O) parameters, as well as the radiative parameters such as the stimulated emission cross-section, the lifetime and the quantum efficiency, were calculated, evaluated and analysed. The results show that their density, refractive index, and field strength increase with Eu3+ ion concentration. Both X-ray diffraction pattern and SEM image represent the amorphous nature of the glasses. The δ values of the samples are positive, and increases with Eu3+ ion concentration. The optical band gap decreases with increase of Eu3+ ion concentration, while the Urbach energy value keeps increase. The J-O parameters for all the samples follow the same trend as Ω2> Ω4> Ω6, and both Ω2 and Ω4 increase first then decrease with Eu3+ ion concentration, 2EuKTTB glass possesses the highest Ω2 (8.05 × 10–20cm2) value. The emission spectra exhibit five peaks in the visible region centering around 579, 591, 613, 652 and 700 nm, respectively, in which the red emission at 613 nm from 5D0→7F2 transition has the highest intensity increasing with Eu3+ ion concentration increase from 0.1 to 2 wt. % then decreasing at higher concentration. The colour coordinates dominate the reddish region of the CIE 1931 diagram, showing that the glasses are potentially suitable for red laser and colour display device applications. The asymmetric intensity ratio (AIR) and correlated colour temperature (CCT) has been also evaluated, both of which increase first and then decrease with Eu3+ ion concentration and almost get their maximum at the doped 2 wt. %. The decay time of 5D0 metastable state to the lower state exhibits single exponential nature. The lifetime decreases with Eu3+ ion concentration, while the quantum efficiency η (%) increases first but decreases after the doped 2 wt. %. 2EuKTTB glass is of the highest value of either the stimulated emission cross-section (7.55 × 10–22 cm2) or the quantum efficiency (90.1 %) among all the glasses.

Zinc oxide and cupric oxide based thin films for solar cell applications

Zinc oxide (ZnO), cupric oxide (CuO) and ZnO/CuO bilayer thin films were prepared on glass substrates using spin coating process followed by annealing at 450 °C for 1 hr in ambient environment. Their structural and optical properties were studied in details using XRD and UV–VIS–NIR spectrometer. XRD patterns depict that all the films were polycrystalline in nature with average crystallite size in the range of 13–15 nm. From optical analysis, it has been shown that the ZnO thin film displayed a large optical band gap (3.22 eV) and high optical transmittance property (∼80%) in the visible range. While ZnO/CuO thin films exhibit large absorbance property unlike ZnO, due to the narrow band gap semiconductor of CuO (1.90 eV) and considered to be utilized for solar cell applications.

Space Environmental Chamber for Planetary Studies.

We describe a versatile simulation chamber that operates under representative space conditions (pressures from < 10−5 mbar to ambient and temperatures from 163 to 423 K), the SpaceQ chamber. This chamber allows to test instrumentation, procedures, and materials and evaluate their performance when exposed to outgassing, thermal vacuum, low temperatures, baking, dry heat microbial reduction (DHMR) sterilization protocols, and water. The SpaceQ is a cubical stainless-steel chamber of 27,000 cm3 with a door of aluminum. The chamber has a table which can be cooled using liquid nitrogen. The chamber walls can be heated (for outgassing, thermal vacuum, or dry heat applications) using an outer jacket. The chamber walls include two viewports and 12 utility ports (KF, CF, and Swagelok connectors). It has sensors for temperature, relative humidity, and pressure, a UV–VIS–NIR spectrometer, a UV irradiation lamp that operates within the chamber as well as a stainless-steel syringe for water vapor injection, and USB, DB-25 ports to read the data from the instruments while being tested inside. This facility has been specifically designed for investigating the effect of water on the Martian surface. The core novelties of this chamber are: (1) its ability to simulate the Martian near-surface water cycle by injecting water multiple times into the chamber through a syringe which allows to control and monitor precisely the initial relative humidity inside with a sensor that can operate from vacuum to Martian pressures and (2) the availability of a high-intensity UV lamp, operating from vacuum to Martian pressures, within the chamber, which can be used to test material curation, the role of the production of atmospheric radicals, and the degradation of certain products like polymers and organics. For illustration, here we present some applications of the SpaceQ chamber at simulated Martian conditions with and without atmospheric water to (i) calibrate the ground temperature sensor of the Engineering Qualification Model of HABIT (HabitAbility: Brines, Irradiation and Temperature) instrument, which is a part of ExoMars 2022 mission. These tests demonstrate that the overall accuracy of the temperature retrieval at a temperature between −50 and 10 °C is within 1.3 °C and (ii) investigate the curation of composite materials of Martian soil simulant and binders, with added water, under Martian surface conditions under dry and humid conditions. Our studies have demonstrated that the regolith, when mixed with super absorbent polymer (SAP), water, and binders exposed to Martian conditions, can form a solid block and retain more than 80% of the added water, which may be of interest to screen radiation while maintaining a low weight.

Impact of hydrogenation and annealing on CdSe/ZnS thin film for solar cell application

This research paper reports the importance of CdSe/ZnS thin film in improving optical and electrical properties. These thin films were prepared on a deeply cleaned glass substrate using vacuum thermal evaporation under the pressure of 10–5 torr. These films were arranged into a quartz glass tube for rapid thermal annealing (RTA) at 60 and 120 s using a 500Watt halogen lamp. These films were also arranged in a hydrogen gas chamber at 100psi for hydrogenation. The Thermoelectric properties (TEP) and the Seebeck coefficient increase with increasing annealing time, also with introducing hydrogenation it was growing a lot. The UV–VIS–NIR spectrometer has been used to investigate diversity in the energy band gap by tuning annealing and hydrogenation in the range 300–850 nm. The X-ray diffraction (XRD) have been taken in scope 10° ≤ 2θ ≤ 80°, its outcome conform simple cubic structure with lattice parameter 5.4 and 5.04 A for CdSe and ZnS, respectively. The scanning electron microscope (SEM) results investigate that the crystallinity and grain size increase with annealing time. This work is essential in thin film optical devices and solar cell applications.

A novel bromo-substituted thiophene based centrosymmetric crystals: Thermal, mechanical, and third order NLO properties for the optical limiting applications

A thiophene based bromo substituted novel chalcone derivative (E) -3-(4-bromophenyl)-1-(thiophen -2yl) prop-2-en-1-one (2AT4B) is synthesized and crystals are grown using solution slow evaporation method at ambient temperature. The single crystal XRD analysis is accomplished to confirm the three dimensional structure of the grown crystals and 2AT4B crystallizes with orthorhombic crystal system under centrosymmetric space group Pbca with the lattice parameters a = 6.0073(6) Å, b = 13.9765(14) Å, c = 28.1(3) Å, α=β=γ=900 and V = 2359.3(4) Å3. The functional groups and material purity is confirmed by FT-IR, proton NMR, and carbon NMR techniques. The crystal is subjected to mechanical and thermal analysis using vicker's microhardness test, differential scanning calorimetric, and thermogravimetric measurements and is thermally stable up to 134.04 °C. The synthesized molecule was characterized by UV–Vis–NIR spectrometer. The photoluminescence spectrum reveals violet light emission property 2AT4B crystal. In the visible region, 2AT4B crystal processes extensive optical transmission. In a continuous wave mode, the third-order NLO parameters are measured with Z-Scan technique. The open aperture data was used to study the optical limiting behaviour of chalcone crystal. Nonlinear optical studies show that the 2AT4B crystal is a promising source for applications in photonic and optical power limiting devices.