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Recent increase in the global consumption of pharmaceutical compounds has enhanced the economic burden for the human population and increased the accumulation of these pharmaceutical compounds in the environment via wastewater released from treatment plants to various water bodies, such as groundwater and surface water, which poses a severe threat to human health as well as aquatic and terrestrial life. Several conventional treatment techniques available to remove industrial pharmaceutical-active compounds (PACs), such as ozonation, photolysis, photocatalysis, and wetland treatment, for the remediation of wastewater resources. Owing to their unique physicochemical features, natural abundance, and the ability to substitute noble metal catalysts, MoS 2 -based hetero-nanostructured materials have attracted significant interest. This study provides a brief overview of the recent research on the structural properties and synthesis of MoS 2 -based heterojunctions, i.e., traditional type-II, all-solid-state, direct Z-scheme and S-scheme heterojunction photocatalytic systems. The layered 2D structure of MoS 2 -based materials contributes to the high mobility of the photoinduced charge carriers, which makes photodegradation rapid and highly stable. These innovative materials have high surface area, small size, photosensitivity, tunable pore size, and electrochemical and magnetic properties. The large-scale application of MoS 2 as a single semiconductor material remains limited. Essentially, a mechanistic investigation on the separation of photoinduced charge carriers and possible approaches to improve the photooxidative potential of MoS 2 with a maximum recovery rate are needed. Moreover, piezocatalytic route for remediation of the hazardous pharmaceutical is addressed. Finally, a brief, conclusive remark regarding current studies and the unresolved challenges of MoS 2 -based photocatalysts addressing future research. [Display omitted] • MoS 2 and its composites promote photochemical/photoelectrochemical PACs degradation. • MoS 2 in corroboration with peroxides promote decomposition of PACs pollutants. • MoS 2 and its composites promotes PACs degradations via PDS/PMS activation. • MoS2 and its composites promote piezocatalytic PACs abatement. [ABSTRACT FROM AUTHOR]

Efficient electrocatalysts are indispensable for promoting the hydrogen evolution reaction (HER). Existing electrocatalysts are limited by sluggish HER kinetics, higher over potential leading to greater energy demand, instability over time, and low tolerance to impurities. These challenges lead to a lower solar-to-hydrogen conversion efficiency of 2.46% using MoS 2 electrocatalyst in authors' previous research work. Mixed metal oxide/conducting polymer nanocomposites have shown great potential for use in hydrogen evolution reaction (HER) reactors due to their high surface area, excellent catalytic activity, and stability in acidic and alkaline environments. A major requirement for suitable electrocatalyst is a low overpotential for hydrogen evolution, a high tolerance to impurities and a long-term durability which makes it more efficient than traditional electrocatalysts. With this brief background, the present work focuses on the application of CuO/TiO 2 /Polyindole (CTPIN) nanocomposite synthesized with the help of two-step process involving microemulsion and oxidative polymerization techniques. The resulting material was characterized using miscellaneous physicochemical techniques. HRTEM analysis clearly demonstrates the formation of CTPIN nanocatalysts with ultrasmall particle sizes of 10–30 nm. The nickel strip was coated with CTPIN nanoparticles was used as cathode for generating solar hydrogen through membraneless electrochemical water splitting. Membraneless electrolyzers offer a promising and cost-effective substitute to traditional electrolyzers, enabling efficient electrochemical hydrogen generation. At a radiation intensity of 320 W/m2 and under normal working conditions, the CTPIN nanocomposite demonstrated a solar-to-hydrogen generation efficiency of 3.43% which is greater than previous results obtained using MoS 2. The CTPIN electrocatalyst has a high potential for electrocatalytic solar hydrogen generation. The CTPIN electrocatalyst could make it possible to produce hydrogen from clean and renewable energy source. • CTPIN nanoparticles synthesized using microemulsion and oxidative polymerization. • HRTEM analysis reveal formation of 10–30 nm CTPIN nanoparticles. • CTPIN nanoparticles deposited on nickel-strip electrodes for solar hydrogen generation. • CTPIN nanocomposite attained 3.43% solar-to-hydrogen conversion efficiency. [ABSTRACT FROM AUTHOR]

Commercially available polycrystalline silicon solar cells have been studied under varying illumination conditions to evaluate their application in low-concentration photovoltaic systems. The present work explores a detailed analytical framework for determining a broad range of performance indicating parameters for polycrystalline silicon solar cells by using the impedance spectroscopy (IS) technique. The IS measurements show that the diffusion capacitance varies from 1×10 −7 to 5×10 −7 F/cm 2 and diffusion resistance from 0.5 to 770 Ω-cm 2 with the applied bias. The IS measurements also indicated that the effective lifetime of charge carriers decreases with increasing illumination. This study confirms that commercially available polycrystalline silicon solar cells can work satisfactorily under low concentration (<3.5 suns). [ABSTRACT FROM AUTHOR]

A solid-state mesoporous titanium dioxide (mTiO 2 ) layer based hetero-junction solar cell, employing nanoparticles (NPs) of methyl ammonium lead iodide perovskite (CH 3 NH 3 PbI 3 ) as light harvesters has been studied. The optimum performance parameters of CH 3 NH 3 PbI 3 are observed as a function of sintering temperature and confirmed by X-ray diffraction analysis and UV–vis spectrophotometry. A solid-state solar cell with the sandwich structure of mTiO 2 /CH 3 NH 3 PbI 3 /Graphite paste showed a power conversion efficiency of 1.11% tested under standard Air Mass 1.5 Global (1000 W m −2 , AM1.5G) solar spectrum. Two-diode model is used to explore the performance limiting factors of the developed solid-state perovskite solar cell. [ABSTRACT FROM AUTHOR]

Highlights: [•] Low concentration photovoltaic (LCPV) system is designed and developed. [•] Commercially available crystalline silicon solar PV cells used under concentration. [•] Dynamic behavior of LCPV system is modeled and estimated. [•] Real-time analysis of LCPV system is presented. [Copyright &y& Elsevier]

This study investigates the steady-state current–voltage characteristics, electronic and ionic processes and dynamic response of a TiO 2 nanoparticle based dye-sensitized solar cell (DSSC) using impedance spectroscopy and current–voltage measurements. A dye-sensitized solar cell is fabricated with 12.26 μm thick TiO 2 layer, having power conversion efficiency of 2.9% under AM1.5 spectrum with photo-generated current density ( J SC ) of 7.2 mA cm −2 and open-circuit voltage ( V OC ) of 672 mV. The observed electrochemical phenomenon at the TiO 2 –electrolyte interface, in diffusion of electrolyte and in charge transfer at the counter electrode is mathematically modeled using alternating current (AC) electrical equivalent circuit. The effect of temperature and illumination on the steady state and dynamic parameters of dye-sensitized solar cells is also studied. The dynamic resistance of DSSC decreases from 440.7 Ω to 78.6 Ω with increase in illumination level from 20 mW cm −2 to 100 mW cm −2 . [ABSTRACT FROM AUTHOR]

Highlights: [•] Multi-crystalline silicon and amorphous-silicon power plants have been compared. [•] The performance ratio (PR) of the mc-Si power plant ranges from 57.1 to 93.14. [•] For a-Si power plant, PR ranges from 53.72 to 87.64. [•] The a-Si solar PV power plant has high capture losses as compared to the mc-Si. [ABSTRACT FROM AUTHOR]

Abstract: This article explores the potential of 1kWP low-concentration photovoltaic (LCPV) system for commercial purposes. Real-time analysis of in-house developed LCPV system shows better performance than the flat panel PV systems. Under actual test conditions (ATC), the open-circuit voltage (V OC ) decreases with temperature coefficient of voltage ≈−0.061V/K. The dynamic resistance is found to have a positive coefficient of module temperature i.e., dr d /dT≈0.49Ω/K. The annual energy generation of 1kWP LCPV power plant is envisaged as 1747.2kWh/kWP while the annual average daily final yield, reference yield and array yield were 3.76, 5.09 and 4.29h/day, respectively. The annual average daily performance ratio and capacity factor are 72% and 14%, respectively. The annual average daily system losses and capture losses are 0.57 and 0.80h/day correspondingly. [Copyright &y& Elsevier]

Abstract: The estimation of steady state and dynamic parameters is indispensable to extract maximum power from solar photovoltaic system. This article aims to extract steady state and dynamic parameters for a low-concentration photovoltaic system under actual test conditions. A theoretical model is reported to estimate dynamic resistance under varying concentration and temperature for low-concentration photovoltaic system. When the concentration ratio is changed from 1 sun to 5.17 suns the maximum power delivered by low-concentration photovoltaic system increased by threefold. The results show that the higher solar PV module temperature has negative impact on the open circuit voltage for a given concentration with negative temperature coefficient of ≈−0.021V/K. The observed dynamic resistance was in the range of 17.99 to 24.84Ω for the low-concentration photovoltaic system under actual test conditions. [Copyright &y& Elsevier]

Abstract: Modeling and simulation of TiO2 nanorod based DSSC are done to explore the effect of nanorod diameter on the short-circuit current density. The results show that the porosity decreases with increasing diameter of nanorod for a fixed value of inter-rod separation. The short-circuit current density can be improved by optimizing the nanorod diameter. From this study it could be observed that the nanorods of diameter from 65nm to 90nm with a porosity range from 0.43 to 0.66 would result in better performing DSSC. The peak value of current density of 23.96mA/cm2 is obtained for the working electrode with a nanorod diameter of 81nm of length 12μm for N719 dye. [Copyright &y& Elsevier]

Gadolinium gallium aluminum garnet doped with cerium (GGAG:Ce), a promising ceramic scintillator material, is being excessively explored for its high quality optical properties by the bandgap engineering with different Ga/Al ratio. In this study, GGAG:Ce powders were synthesized using a solvothermal method and sintered at 1300 °C to investigate the impact of the gallium-to-aluminum (Ga/Al) ratio on optical characteristics. The results revealed that a decrease in the Ga/Al ratio led to a decrease in particle size. This observation can be attributed to the different reactivity and growth kinetics of gallium and aluminum precursors during the solvothermal process. Perturbations from the optimized Ga/Al ratio of 1.5–1.77 and 1.27 resulted in substantially enhanced photoluminescence (PL) and radioluminescence (RL) spectra intensities. PL lifetime measurements of various Ga/Al ratio exhibit average PL lifetime between 48 and 57 ns. Specifically, the deviations to 1.77 and 1.27 ratios yielded approximately 125 % and 106 %, respectively, in observed luminescent measurements compared to other ratios. This enhancement in PL and RL intensity suggests that the Ga/Al ratio plays a critical role in modulating the optical properties of GGAG:Ce ceramic powders. The results of this study also highlight the importance of the Ga/Al ratio in tailoring the optical or luminescence characteristics of GGAG:Ce powders. [ABSTRACT FROM AUTHOR]

Metal single-electron transistor (SET) and semiconductor quantum dot (QD) are Coulomb blockade (CB) devices having applications in quantum and classical technologies. The quantized confined energy of the confining system increases when the size of this system decreases. This behavior affect transport of charge carrier through SET significantly. This paper presents the results of investigation on the effect of quantized confining energy on the operation conditions of the single-electron transistor, known as quantum Coulomb blockade phenomena. Moreover, modified mathematical description of operation conditions and the quantum Coulomb blockade region of SET has been presented. • New theoretical insights in to quantum Coulomb blockade with reference to SET. • Conditions of achieving tunneling transport through QDs depend on their size. • Addition charge energy required to charge QD increases when the radius of QD decreases. • Smaller size of QDs provides a greater stability to SET for working under high temperature conditions. [ABSTRACT FROM AUTHOR]

Hydrogen due to high energy density and ecologically benign characteristics can become an excellent energy carrier for a sustainable energy economy and to appease the energy demand of humankind. Moreover, cost-effective and long-lasting photocatalysts can make the hydrogen generating process more economical and suitable. Recently, MXene have become one of the most sought-after composite materials for photocatalytic hydrogen generation. However, the photocstalytic performance can be further enhanced by doping with other semiconductor materials. Transition metal chalcogenides (Transition metals = Cu, Co, Ni, Zn, Cd, Mo, W)/MXene composites and mixed transition metal chalcogenide/MXene nanocomposites have been extensively investigated for the photocatalytic hydrogen generation. These materials possess unique two-dimensional layered structure that ameliorates the photocatalytic water splitting performance by increasing the light adsorption even at low photon flux density. The 2D design assists in reducing the distance necessary to transverse charge carriers to the surface. Because the layered structure tends to trap electrons in the ultrathin layers, 2D materials have unusual optoelectronic properties. In-plane covalent bonding assisted the creation of various heterojunctions and heterostructures in these 2D materials. Water splitting and hydrogen production are aided by the high surface area of these 2D materials. Due to its diverse elemental composition, unique 2D structure, good photoelectronic characteristics, large surface area, and many surface terminations. The design and production of many types of materials used as catalysts for the hydrogen evolution process are discussed in this article. • Hydrogen due to high energy density and ecologically benign energy storage material. • Transition metal chalcogenides (TMCs)/MXene composites are efficient photocatalyst for hydrogen generation. • Cd x Zn 1-x S/Ti 3 C 2 (MXene) assisted in promoting hydrogen generation at very high rates (15,035.81 μmol g−1 h-1). • Doping with noble metal (MXene@Au@CdS) enhances the higher hydrogen generation yield with 17,070.43 μmol g−1 h−1. [ABSTRACT FROM AUTHOR]

In the urban areas the demand of solar power is increasing due to better awareness about the emission of green house gases from conventional thermal power plants and significant decrease in the installation cost of residential solar power plants. But the land cost and the under utilization of available space is hindering its further growth. Under these circumstances, solar photovoltaic system installation needs to accommodate the maximum number of solar panels in either roof-top or land-mounted category. In this article a new approach is suggested to maximize the total number of solar panels in a given area with enhanced energy output without compromising the overall efficiency of the system. The number of solar panels can be maximized in a solar photovoltaic energy generation system by optimizing installation parameters such as tilt angle, pitch, gain factor, altitude angle and shading to improve the energy yield. In this paper mathematical analysis is done to show that the capacity and generated energy can be enhanced by more than 25% for a given land area by optimization various parameters. [ABSTRACT FROM AUTHOR]

In the present article, the direct current and alternating current characterization techniques are employed to investigate the losses during interfacial charge transport in dye-sensitized solar cell (area: 3.78 cm 2 ) having a power conversion efficiency of 4.32%. The analysis of current–voltage characteristics depicts that the loss in photocurrent density is about 1–1.5% at low forward bias, ∼8% at knee voltage and ∼79% at open circuit voltage. The electrochemical impedance spectroscopy measurement leads to the direct determination of recombination resistance, chemical capacitance, charge transport resistance and double layer capacitance. The current–voltage characteristics obtained from the impedance parameters allows separating the contributions of different resistive processes on the overall conversion efficiency. The experimental results along with the analytical model provide an insight into the electric power loss mechanism, which is useful for analyzing performance of other upcoming devices with a similar working mechanism like perovskite sensitized solar cells. [ABSTRACT FROM AUTHOR]

This article focuses on the identification of key features that are responsible for the discrepancies in the performance of silicon solar cells fabricated on multicrystalline silicon under the identical conditions. In an experimental approach, direct current (DC) measurement coupled with alternating current (AC) characterisation technique has been employed. The scanning electron microscope analysis reveals an average grain size of few micrometres for all the solar cells and the top surface of least efficient solar cell contains the impurity precipitates with deep cone shaped holes or pits. The DC measurement reveals that the photocurrent density loss follows an exponential behaviour with respect to the current–voltage characteristics for all the solar cells. The analysis of − dV / dJ versus ( J SC − J ) −1 plot and the variation of ideality factor with junction voltage demonstrate that the higher resistive and recombination losses dominate the performance of least efficient solar cell. Impedance Spectroscopy (IS) technique is used to quantify and decouple the various photovoltaic parameters associated with the different physical processes. A lower value of shunt resistance and minority carrier lifetime along with the higher value of series resistance contribute to the higher resistive loss and surface recombination. The experimental results along with the analytical model provide an insight into the loss mechanisms and the use of a simple tool that can be integrated with the conventional photovoltaic testing. [ABSTRACT FROM AUTHOR]

The utilization of additive manufacturing techniques, especially Digital Light Printing (DLP), in fabricating CsI:Tl scintillator films demonstrates considerable potential for streamlining the production of scintillators tailored for X-ray imaging applications. This research focuses on the fabrication of CsI:Tl-based composite plastic scintillator thin films. In this study, circular films measuring 1-inch in diameter and 0.1 mm & 0.2 mm in thickness are being produced and tested for gamma photon counts under alpha and gamma radiation. To establish the stopping power range of the films, a Monte Carlo based GEANT4 simulation has been carried out. Additionally, investigations into their suitability for X-ray imaging applications are being conducted, revealing the spatial resolution of the films (0.2 and 0.1 mm) between 100 and 130 μm and 1.26 lp/mm with a contrast range of 4.0–12.3 %. The observed decrease in spatial resolution and contrast for the 0.2 mm thick film is attributed to the thickness increase exacerbating the scattering phenomenon while simultaneously enhancing the X-ray stopping power. This highlights the significance of inherent trade-off between maximizing spatial resolution and compromising light yield of 0.1 mm films compared to the 0.2 mm thick film. By utilizing 3D printing, this approach offers a cost-effective and time-efficient method for producing thin-film scintillators with enhanced flexibility and customization options compared to conventional methods. • CsI:Tl microscrystal-based scintillator thin films were fabricated using DLP 3D printing for X-ray imaging. • 3D-printed scintillator films with 1-inch diameter and 0.1 mm, 0.2 mm thicknesses showed balance in spatial resolution and X-ray stop. • Monte Carlo GEANT4 simulation showed 96% of alpha particles stopped in 0.1 mm films and 98.5% in 0.2 mm films. • The 0.2 mm film had higher luminescence and photon counts for X-ray imaging, while the 0.1 mm film had better spatial resolution (100 μm, 1.26 lp/mm). • Future research will explore film thickness trade-offs, use nanoparticles for better performance, and address hygroscopicity with hydrophobic surfactants. [ABSTRACT FROM AUTHOR]

The present work reports an experimental study for the direct determination of broad range of performance indicating parameters of polycrystalline silicon solar cell by using direct current (DC) and alternating current (AC) characterization techniques. The DC characterization technique is employed to obtain the characteristic features of solar cell like fill factor, efficiency, series resistance and ideality factor. The AC characterization technique provides resolved electrical response of the resistances and capacitances of p–p + (back surface field) and n + –p junctions, series resistance of the solar cell as well as the lifetime of minority charge carriers. The current density–voltage ( J – V ) characteristics demonstrate the existence of non-linear shunt paths and higher charge recombination for a less efficient polycrystalline silicon solar cell. The impedance spectroscopy results reveal that a low fill factor observed for less efficient silicon solar cell is due to the hindrance of charge carriers in active layer and low Fermi level degeneracy at Aluminium/Silicon (Al/Si) interface. The obtained DC and AC parameters and their underlying mechanisms are also examined using the proposed theoretical model. The results presented here demonstrate that the DC technique coupled with AC characterization technique can be quantitatively utilized for the investigation of unexplored fundamental and applied aspects of silicon solar cells. [ABSTRACT FROM AUTHOR]

This work describes the role of relative humidity (R.H.) on the performance degradation of methyl-ammonium lead-iodide (CH 3 NH 3 PbI 3 ) based hole transport material (HTM) free hetero-junction perovskite solar cell. It has been observed that the power conversion efficiency (η) of perovskite solar cells decreases from 4.52% to 1.28% with increases in R.H. from <40% to 75%. A semi-analytical optoelectronic model is further developed to explore the effect of humidity on performance limiting parameters, i.e. absorption coefficient, diffusion length. The shunt resistance decreases whereas space charge region width and series resistance increases with respect to the increase in R.H. from <40% to 75%. The charge carrier losses through recombination, spatial relaxation and thermalization are also analysed and found to increase from 76% at <40%R.H to 84% at 75%R.H. [ABSTRACT FROM AUTHOR]

A perovskite heterojunction solar cell is fabricated with architecture of hole transport material (HTM) free discrete electrode. The morphological, structural and optical properties are studied by FESEM, XRD and UV–Vis spectrophotometry techniques. A single diode model has been used to investigate the cell characteristics. The interface between TiO 2 and CH 3 NH 3 PbI 3 layer is found analogous to Schottky diode that acts as a heterojunction for excitation and dissociation of charge carriers due to the existence of an internal electric field at the junction. The SCAPS simulation is done to explore the role of interface defects and band offsets. Device simulation has shown an improvement of 16%, 6% and 25% in V OC , FF and η respectively with incorporation of the HTM layer in device structure. [ABSTRACT FROM AUTHOR]

The present work describes a method for the development of hole-transport material (HTM) free, solution processable perovskite solar cell under ambient air conditions. This study mainly focuses on the working mechanism of the perovskite solar cell using impedance spectroscopy and current–voltage ( I – V ) techniques. Impedance spectroscopy reveals various interfacial processes in terms of resistive and capacitive elements, which provided an insight into the charge transport through the junction and bulk of the FTO–perovskite solar cell. The study also provides a new architecture of pervoskite solar cell, where in conducting polymer (poly-aniline) as a hole-extraction electrode increases the efficiency by 21% relative to FTO electrode. This article systematically explains the bridging and trapping effects within the perovskite solar cells for the first time. [ABSTRACT FROM AUTHOR]

This paper provides an overview of the battery thermal management systems (BTMSs) based on the studies carried out by different researchers across the globe. The focus is on enhancing the thermal performance of the battery with the selection and incorporation of a suitable thermal management system. In addition to this, the performance enhancement of lithium-ion (Li-ion) battery systems using supercapacitor (SC) in parallel topological connection, have been discussed. The design options in BTMS and the desired level of sophistication are discussed in this study. For ensuring the performance and safety of Li-ion batteries, a suitable BTMS must be designed to regulate and control the thermal load of the batteries. This would not only result in safety but also ensure longer battery life. This paper presents the summary of recent developments in the direction of BTMS with direct and indirect cooling methods and provides significant insights into the use of SC for reducing the thermal load on the Li-ion batteries, which in turn can help in reducing the cost and weight of BTMS required for energy-efficient electric vehicles (EVs). • Air-based BTMS have low thermal conductivity and heat transferring efficiency. • Liquid-based BTMS can lead to serious thermal runaway problem upon leakage. • PCM-based BTMS is costly and affect the weight of battery module. • Thermoelectric generator based BTMS consumes significant amount of energy. • Thermal runaway of Li-ion batteries is still an open and challenging problem. [ABSTRACT FROM AUTHOR]