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Preferential binding of base pair units with metallic ions within deoxyribonucleic acids (DNA) to form metal‐DNA complexes are well studied and understood. Excitingly, such natural processes have been utilized "artificially" for designing and fabricating nanometallic structures and patterns primarily using double stranded DNA. However, little or no effort has been given to ribonucleic acid or RNA in this aspect. Therefore, in this work we study the scaffolding effect of RNA on metalizing silver (Ag) ions and further the diffusion of majority of the Ag‐RNA complexes towards artificially introduced cut or scribed edges as a result of the coffee‐ring effect. Upon removal of the RNA scaffold, metallic nanostructures remain along the line of the cut corresponding to the micrometre scale length of the cut, exercising some amount of control and manipulation of parameter. Other parameters such as the height and diameter may directly be related to the concentration and diffusion of the Ag‐RNA complexes, while gap size related to the cut width. We anticipate that further in‐depth studies will be required before a comprehensive model could be proposed for highly controllable and flexible nanostructure and nanowire fabrication using nucleic acid scaffolding techniques. [ABSTRACT FROM AUTHOR]

A Photoanode in dye sensitized solar cell is responsible for photoabsorption and conduction of the generated electrons for which TiO 2 is a highly employed material due to its non-toxic nature and low cost. This study reports a convenient and facile method to prepare un-doped and magnesium (Mg) doped TiO 2 thin films using Aerosol assisted Chemical Vapor deposition on Indium doped Tin oxide substrates. The as prepared films were subjected to morphological and structural characterizations as well as the optical absorption, band gap and surface area measurements of films. The studies indicated that Mg substituted Ti in the TiO 2 lattice and formed new energy levels which decreased the band gap of the doped films. Moreover, increasing the concentration of Mg shifted the optical absorption of the films from ultra-violet region to the visible region. The IV measurements of the DSSCs fabricated using 2 mol% Mg doped TiO 2 film, N719 dye, I − /I 3 − redox electrolyte and platinum sputtered on ITO counter electrode, revealed approximately twofold increase in overall efficiency of DSSCs as compared to undoped TiO 2 based DSSC. The increase in V oc and J sc , as well as the efficiency of 6.1%, is an indication that 2 mol% Mg doped TiO 2 film is a potential candidate as a photoanode material in DSSC. [ABSTRACT FROM AUTHOR]

The self-patterned silver (Ag) nanowires on Indium Tin Oxide (ITO) were developed and exploited as the enzyme-free sensor probes for glucose detection. Deoxyribonucleic acid (DNA) template increased the capillary force channels of Ag and facilitated the homogeneous and high mobility of Ag-DNA toward the scribe via the coffee ring effect. The subsequent removal of DNA template from Ag-DNA/ITO through the enzymatic hydrolysis process led to the formation of Ag nanowires on ITO. Under alkaline conditions, Ag nanopatterns developed on ITO realized the considerable enzyme-free glucose sensor performances. The fabricated sensor system is reproducible and stable and was pertained with an analysis of spiked human blood serum, where it provided excellent recoveries. Thus these findings have not only showered insights on the self assembly of Ag nanoparticles without the exploitation of any surfactants and harsh conditions but have also provided the fundamental perceptive on the influences of self-assembled nanowires in enzyme free glucose sensor applications. [ABSTRACT FROM AUTHOR]

Photoanode is one of the most important components in dye-sensitized solar cells (DSSCs) for which oxide ceramics are among the top choices. It has been established that the metal doping can introduce structural defects in oxide ceramics such as in titania lattice which can result in increase in photo-absorption of solar cells. Metals such as Cu being inexpensive and readily available, have potential to cause phase transformation in titania at lower temperature supportive to cell performance. However, there is not enough data available in the literature on performance of DSSCs based on Cu-doped titania photoanode. In this work, we have synthesized undoped and doped titania nanoparticles by wet-chemistry routes. Various process routes such as effects of annealing temperature, Cu concentration, pore former, etc. were employed to investigate the structural, thermal and electrical performance of doped and undoped materials and thin films for DSSCs. For qualitative and quantitative analyses, techniques such as X-ray diffraction, scanning electron microscopy, thermal analyses, molecular spectroscopy and potentiostat were employed. Studies have revealed that dopant existed in the form of CuO in nanoparticles and thin films. Cu doping assisted in reduction in particle size and band gap, which was further verified by red absorption shift. IV measurements of the cells fabricated with Cu-doped titania photoanode, N3 dye, I − /I 3 − electrolyte and gold coated FTO counter electrode, revealed an 11% increase in V oc, compared to V oc of cell made with similar components but using undoped titania photoanode. The inclusion of carbon microspheres caused formation of cavities into the photoanode made with titania and Cu:Titania and increased the porosity and surface area for greater dye adsorption. It was found that porosity increased from 31% to 42% by adding in-house fabricated 2.5 wt% carbon microspheres into 3 wt% Cu-doped titania thin films. [ABSTRACT FROM AUTHOR]

Rare earth metals like erbium oxide (Er 2 O 3) show outstanding photocatalytic properties. However, its high recombination rate and low surface area limit its performance. Therefore, various metal oxide composites with Er 2 O 3 have been reported to improve their photocatalytic and optoelectronic properties. In this study, a composite of Er 2 O 3 and zinc oxide (ZnO) was synthesized using the sol-gel combustion method to enhance its surface area. Moreover, molybdenum (Mo) was loaded on the matrix to suppress the charge recombination. The detailed characterizations were conducted by employing X-ray Diffraction (XRD), Raman Spectroscopy, Field Emission Scanning Electron Microscopy (FESEM), Brunauer–Emmett–Teller (BET) analysis, Photoluminescence (PL) spectroscopy and UV–Vis spectroscopy. BET analysis revealed the enhancement in surface area by adding ZnO and Mo (from S BET = 29.07 m2/g to S BET = 45.71 m2/g). Additionally, the loading of Mo enhanced the immobilization of carriers that facilitate the photooxidation process and suppressed the electron-holes recombination (from 800 counts to 100 counts) as confirmed by the PL spectroscopy. Photocatalytic studies were comparatively analyzed by degradation of textile dye named methylene blue (MB). The efficiency of Er 2 O 3 improved by up to 80% by adding the ZnO and Mo. The composite of Er 2 O 3 with ZnO and loading of Mo, not only improved the photocatalytic properties but also improved the electrical properties of the Er 2 O 3 (σ = 4.4 × 10−4 Sm−1 to σ = 5.1 × 10−4 Sm−1) as confirmed by the Hall Effect. Due to enhancement in properties, the proposed material can be rendered as one of the most suitable candidates for optoelectronic applications. [ABSTRACT FROM AUTHOR]

Ca-doped TiO2 films were synthesized by the modified sol-gel method and employed as the electron transport material of perovskite solar cells (PSCs). Morphological, optoelectronic, thermal, and electrical studies of thin films were investigated through XRD, RAMAN, SEM, AFM, UV-Vis, FTIR, and IV characteristics. Ca doping was detected with the help of structural properties while morphological analysis revealed that thin films based on Ca-doped titania are crack-free, homogenous, and uniformly distributed. Further optoelectronic properties have shown a promising conversion efficiency of 9.79% for 2% Ca-doped titania followed by 1% Ca-doped titania, while 3% have shown the lowest conversion efficiency among these prepared samples. The 2% an optimized doping of Ca has shown an almost two-fold increase in conversion efficiency in comparison to pristine TiO2, along with an increase in current density from 15 mA⋅cm−2 to 19.3 mA⋅cm−2. Improved energy efficiency and higher current density are attributed to faster electron transportation; moreover, the optimized percentage of Ca doping seems to be an effective approach to improve the PSCs' performance. [ABSTRACT FROM AUTHOR]

TiO 2 is a wide bandgap semiconductor commonly used as a photoanode material in dye sensitized solar cells (DSSCs). However, low absorption of TiO 2 in visible range of solar spectrum limits its performance in DSSCs. A multistep electrophoretic deposition (EPD) process was used to improve the morphology of the mesoporous films and high quality TiO 2 films were fabricated. Meanwhile, the optical absorbance was enhanced by a convenient and simple surface modification method using tin (Sn). The prepared films were subjected to morphological, optical, elemental, and phase analyses. It was observed that multistep EPD produced high quality films at various electric fields. Moreover, the surface modification was achieved using sonochemical deposition of Sn+ on the film which enhanced its photo-absorption. The current density (J) versus voltage (V) characteristics of Sn/TiO 2 film deposited at 20 V based DSSC showed approximately twofold increase in the efficiency of the solar cells. Improved open-circuit voltage (V oc), short-circuit current density (J sc) and efficiency (η) of the DSSCs as well as significantly high fill factor indicated that the surface modified EPD film is a potential candidate as a photoanode film in DSSCs. • A multiple step electrophoretic deposition method for TiO 2 film. • Effective enhancement in TiO 2 light absorption towards visible region using surface modification. • Fabrication of porous thin films without compromising the surface area of the films. • Enhancement in photovoltaic performance of the dye sensitized solar cells due to effective surface modification using tin. [ABSTRACT FROM AUTHOR]

Developing a highly active, cost-effective, environmentally benign and stable photocatalyst for solar hydrogen production is challenging. In the present study, Tin (II) oxide silicate (Sn 6 SiO 8) thin films are deposited on FTO coated glass substrate from precursor [bis(trimethylsilanolato)tin], Sn 6 O 4 (OSiMe 3) 4 compound by AACVD technique at 550 and 500 °C. Fabricated thin films were then physically analyzed by XRD, Raman, XPS, SEM, and EDX analysis to verify the formation of Sn 6 SiO 8 in granular and compact morphology respectively, the optical band gap of 2.48 and 2.40 eV were recorded by UV–Visible spectrophotometry. Photoelectrocatalytic response of the Sn 6 SiO 8 electrode proved that it is the n-type semiconductor and, therefore exhibits higher photocurrent of 3.79 and 3.13 mA/cm2 at +0.71 V versus Ag/AgCl was found for the photoelectrode deposited at 550 and 500 °C which led to better stability for 1200 s. [Display omitted] • Optical and optoelectronic properties of Tin (II) oxide silicates thin films by AACVD Method. • Optical band gap of 2.48 eV improves the photoelectrochemical behaviour of Sn 6 SiO 8 thin film. • Photocatalytic activity of Sn 6 SiO 8 thin film fabricated at 550 °C is 1.3 time higher than 500 °C. [ABSTRACT FROM AUTHOR]

The excess emission of greenhouse gases (GHGs) such as CO2 and CH4 is posing an acute threat to the environment, and efficient ways are being sought to utilize GHGs to produce syngas (H2, CO) and lighter hydrocarbons (HCs). In this study, the dry reforming of methane (DRM) has been carried out at 700 °C using La2O3 co-supported Ni/MgAl2O4 nano-catalyst in a fixed bed thermal reactor. The catalyst is characterized using various techniques such as XRD, FESEM, EDX-mapping, CO2-TPD, H2-TPR and TGA. The modified MgAl2O4 shows the flake type structure after the addition of La2O3. The TPR and TPD analysis shows the highly dispersed metal and strong basic nature of the catalyst consequently enhances the conversion of CO2 and CH4. The highest conversion for CH4 is 87.3% while CO2 conversion is nearly 89.5% in 20 h of operation time. The selectivity of H2 and CO approached 50% making the H2/CO ratio above unity. In the longer time-on-stream (TOS) test, the catalyst shows elevated potential for longer runs showcasing better catalytic activity. The stability of the catalyst is indicated via a proposed reaction mechanism for DRM in operating conditions. Moreover, TGA indicates the lower weight loss of spent catalyst which ascribed the lower formation of carbon during TOS 20 h. [ABSTRACT FROM AUTHOR]

Ni-Co loaded hemp-derived activated carbon (AC) catalyst is synthesized by the wet impregnation method for steam methane reforming (SMR) for hydrogen production. The monometallic and bimetallic metal (Co, Ni) catalysts were synthesized over activated AC with 5 wt% by the wet impregnation method and characterized by using various techniques. XRD and SEM results suggested that the catalysts with small metal crystallites promote a better dispersion of highly porous AC.The catalytic assessment of all synthesized catalysts for SMR was carried out in a thermal fixed bed reactor at 750 °C, WHSV 2000 mL CH4 g−1 h−1, and S/C of 2.0. The catalytic results showed that among all the investigated samples, monometallic cobalt catalyst (5% Co@AC) exhibited the best results in terms of CH4 conversion (97.17%) and H2 production (66.08%). While the 5% Ni@AC and 5% NiCo@AC show a CH4 conversion of 90.28% and 92.52%, respectively, whereas the H2 production was 61.02% and 65.89%. [ABSTRACT FROM AUTHOR]

The affordable transportation industry has been severely compromised in 2022 as a consequence of the unexpected surge in the price of fossil fuels. By 2050, the transportation industry is forecasted to expand twice, leading to a variety of issues, such as fossil fuel depletion and environmental emissions. As a result, worldwide trend toward electrifying transport, with energy production originating from both traditional and carbon-free sources. Therefore, consumers of electric vehicles require convenient access to the services of charging stations around the country. This research investigates existing fuel station rooftops for the deployment of the grid-connected photovoltaic (GCPV) system electric vehicle charging stations (EVCS), design, and performance analysis of Pakistan's cities. A mathematical model of the GCPV EVCS under consideration has been described. Three cities in Pakistan: Multan, Lahore, and Islamabad-EVCS powered by photovoltaics and the utility grid have been designed and their comparison of the techno-economic performance indicators have been done through System Advisor Model (SAM) software. To comprehend the impact of uncertainty on the functionality of the GCPV EVCS, sensitivity analyses were conducted at all three designated cities in Pakistan. With this strategy, Pakistan will be able to reduce its greenhouse gas emissions to the level required by the Paris Agreement. [Display omitted] • GCPV system for EVCS was designed for installation on existing fuel stations in various cities of Pakistan. • Using System Advisory Model, Photovoltaics modules and utility grid models were integrated. • An annual energy, economic, and technical feasibility study was developed. • LCOE findings were 3.87 cents/kWh, 4.07 cents/kWh, & 3.85 cents/kWh in Multan, Lahore, and Islamabad respectively. • Proposed charging infrastructure would accelerate the sustainable growth in EV adoption. [ABSTRACT FROM AUTHOR]

Syngas is a valuable entity for downstream liquid fuel production and chemical industries. The efficient production of syngas via catalytic partial oxidation of methane (CPOM) is an important process. In this study, partial oxidation of methane (POM) was carried out using CaO decorated TiO2 catalysts. The catalysts were synthesized employing the sol-gel method, while the decoration of TiO2 with CaO was achieved in an aqueous solution by wetness impregnation method. The prepared catalysts were characterized by employing XRD, Raman, TG-DTG, and SEM-EDX for structural and morphological analysis. On testing for POM, at 750 °C the catalysts demonstrate excellent CH4 conversion of 83.6 and 79.5% for 2% and 3% CaO loaded TiO2, respectively. While the average H2/CO ratio for both 2% and 3% CaO loaded TiO2, 2.25 and 2.28, respectively, remained slightly above the theoretical value (H2/CO = 2.0) of POM. The improved POM performance is attributed to the optimally loaded CaO on the TiO2 surface that promotes the reaction where TiO2 support ensure less agglomerated particles, resulting into a fine distribution of the active catalytic sites. [ABSTRACT FROM AUTHOR]

• Roof Top Floating PV test bench for the hot climatic condition. • Floating PV systems reduced water evaporation by 17% and 28%. • Lowering the front temperature of FPV modules by 2–4%. • The optimal tilt angle of FPV necessary for maximum power. Floating Photovoltaic (FPV) is a relatively new concept for producing clean green energy. This study presents the results of an experimental investigation of a small-scale FPV system. The goal is to evaluate and compare the thermal and electrical performances of mono and polycrystalline photovoltaic modules used in FPV with those of On Ground PV (OPV) systems with a similar nominal capacity. To accomplish this, a test bench consisting of an FPV and an OPV system has been established. The results show that when the water body is partially covered with a Floating PV system, water evaporation is reduced by 17%. And it is reduced by around 28% when fully covered. It was also found that water bodies provide an adequate cooling effect. Lowering the front temperature of Floating PV modules by 2–4% and the back temperature by 5–11% compared to similar On-ground PV modules. Thermal imaging revealed that at 0 degrees of tilt, the front temperatures of the modules are uniform. Still, as the tilt increases, a temperature gradient is observed between the bottom and middle parts of the modules. In addition, an experimental test was performed to compare the power generation of Floating PV at varying tilt angles. The test results show that the Floating PV system produces the most energy when installed at the annual optimal tilt angle. As a result, for FPV, adjusting the Photovoltaic panels to their optimized tilt angle is also recommended. While Floating PV system produces 20–28% more energy than the on-ground PV system at 0°as compared to the optimal tilt angle. [ABSTRACT FROM AUTHOR]

Hybrid organic/inorganic perovskite solar cells (PSCs) have acquired significant consideration due to high power conversion efficiency (PCE). In PSCs, electron and hole extraction layers have a significant influence on their overall performance. In inverted p-i-n structure-based PSCs, NiO x has been frequently employed as a hole transport layer (HTL) due to its simple processing, wide bandgap, high optical transmittance, excellent chemical stability, and low processing temperature for large-scale fabrication. However, NiO x suffers from low electrical conductivity. Doping of NiO x is an effective technique employed for enhancing electrical as well as optical properties. Herein, the praseodymium doped NiO x (Pr-NiO x) was synthesized by sol-gel method, and films were fabricated to investigate the effect of Pr dopant on the optoelectronic properties and photovoltaic performance of PSCs. Results indicated that Pr doping significantly improved the hole mobility by about threefold and conductivity of NiO x films from 4.68 × 10-6 S cm-1 to 8.27 × 10-6 S cm-1. Moreover, it also enhanced the compactness and interfaces of NiO x HTL. PSCs based on 4 % Pr-doped NiO x HTL- yielded PCE of 9.35 % which is 32.43 % more than the PSCs fabricated using undoped NiO x HTL. The enhanced PCE of PSC devices with Pr-doped NiO x could be attributed to efficient extraction of a hole from an active absorbing layer of perovskite thereby, lowering the probability of unsuitable charge carrier recombination. This work exhibits that Pr-doped NiO x thin film could be a promising alternative material for efficient and stable inverted PSCs. [Display omitted] • Praseodymium doped NiO x films were fabricated using facile sol gel method. • The effect on the properties of NiO x on Pr doping were investigated. • Pr-doping effectively improved the optoelectronic properties of NiO x. • 4 % Pr-doped NiO x HTL based PSC exhibited 9.35 %, PCE, 32.43 % more than undoped NiO x. [ABSTRACT FROM AUTHOR]

• FPV on the non-utilizable urban lakes in Pakistan have been investigated. • The power potential of solar PV system deployed non-utilizable urban lake turns out to be 4.47 MW. • Cleaning of the FPV systems is much easier and cost effective compared to the on-ground PV systems. • The temperature drops around the water bodies increases the capacity factor yielding more energy and results in Levelized Cost of Energy for a 100 kW FPV system to be 5.64 ¢/kWh. Water bodies like small lakes, canals, and rivers in urban areas serve to be a way forward to deploy photovoltaic technology with no constraints to involve land procurement. This article aims to estimate the potential deployment of a floating photovoltaic system on an urban lake site to assess its scope and compare it with a similar specification on-ground photovoltaic system. System Advisor Model (SAM) has been used for techno-economic analysis of a site in Pakistan. The technical analysis involves observing the effect of real time temperature drop and calculation of water reduction efficiency for FPV systems. The economic parameters like net present value (NPV) and payback period are used to judge the economic feasibility of the floating photovoltaic deployment project. The floating photovoltaic deployment in an urban area is subject to soiling as the water reservoir being used exists in an area close to or within the city boundaries. The required cleaning water costs a one-time extraction rate of $1435, while for a floating photovoltaic system, the extraction cost is estimated to be $1.35. Under standard temperature conditions (STC) one-year capacity factor turns out to be 0.70% more, producing an additional energy yield of 64 kWh/kW for lake scenarios when a 10 °C temperature drop is considered. The total power potential for the entire NUST Lake turns out to be 4.47 MW. A 1 MW FPV system in NUST lake would result in a water reduction efficiency of 11.6%/year. Under standard temperature conditions, the net present value for the on-ground system becomes negative while it remains optimistic for the floating photovoltaic system as no land costs are required. Similarly, once the land cost is included in the feasibility analysis, the payback period for the on-ground system goes beyond 15 years which is only 5.37 years for a floating photovoltaic system signifying the economic feasibility of the floating photovoltaic project. [ABSTRACT FROM AUTHOR]

Summary: In this study, cobalt (Co) loaded Sr2TiFeO6‐δ (STF) double perovskite was synthesized using a modified nitrate combustion method for the application in catalytic decomposition of methane (CH4) for hydrogen (H2) production in a fixed bed reactor. The physicochemical properties of the catalyst were analyzed using X‐ray diffraction (XRD), scanning electron microscopy (SEM), energy‐dispersive X‐ray spectroscopy, N2 adsorption‐desorption, thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy. The catalyst showed a stable crystalline behavior with a uniform dispersion of Co over STF. The different compositions with varying Co loading were tested for methane decomposition at 850°C and constant flow rate. The 5% Co/STF achieving a maximum CH4 conversion of ~95% with an H2 yield of ~49%. Five percentage Co/STF showed excellent catalytic activity and stability for 46.5 hours time on stream without any indication of performance degradation. The spent catalyst was also analyzed using XRD, SEM, and TGA. The carbon deposited is shaped as carbon nanotubes that are a byproduct and also assist in metal exsolution in high‐temperature processes. The use of STF shows the excellent potential showed by perovskites, which are stable in reducing environments, as support materials for methane decomposition. [ABSTRACT FROM AUTHOR]

• Inter-farm wake losses intensify due to uncoordinated wind farm development. • Repowering augments the power generation capacity of existing wind farms. • Coupled mesoscale and microscale simulations provide a swift repowering analysis. • Power is increased by vertical and horizontal relocation of wake affected turbines. This study explores the effects of inter-farm wakes and proposes staggering schemes that are most suitable for optimization of existing wind farm arrays to mitigate the effects of compound wakes. The case study considers a total of 9 out of 33 most deteriorated wind turbine for a microscale numerical analysis using the steady-state actuator disk model coupled with the mesoscale boundary condition data. Furthermore, the convective atmospheric boundary layer has also been considered. For vertically staggered layouts, the effect of the inter-farm wakes appeared mild at 100 m, modest at 80 m, and high at 60 m; as the maximum velocity deficit observed under the influence of compound wakes is approximately 13.3%, 14.1%, and 15.2%, respectively. Onsite recorded power data has been used to validate the baseline predicted powers at 80 m hub height. Both vertical and horizontal staggering options have been assessed for partial repowering. By elevating the turbines to a 100 m hub height, the cumulative power generation from the 9 × turbines increased by approximately 13.5% while reducing the hub height to 60 m decreased the power output by approximately 11.5% of that of the baseline at 80 m hub height. Further increase in cumulative power of up to 23% compared to existing layout is achieved by applying a lateral repositioning of 3 × underperforming turbines now positioned at 100 m hub height. This paper hence presents an applied insight for partial repowering of onshore wind farms affected by inter-farm wakes. [ABSTRACT FROM AUTHOR]

The catalyst has a significant role in gas processing applications such as reforming technologies for H 2 and syngas production. The stable catalyst is requisite for any industrial catalysis application to make it commercially viable. Several methods are employed to synthesize the catalysts. However, there is still a challenge to achieve a controlled morphology and pure catalyst which majorly influences the catalytic activity in reforming applications. The conventional methods are expansive, and the removal of the impurities are major challenges. Nevertheless, it is not straightforward to achieve the desired structure and stability. Therefore, significant interest has been developed on the advanced techniques to take control of the physicochemical properties of the catalyst through non-thermal plasma (NTP) techniques. In this review, the systematic evolution of the catalyst synthesis using NTP technique is elucidated. The emerging DBD plasma to synthesized and effective surface treatment is reviewed. DBD plasma synthesized catalyst performance in reforming application for H 2 and syngas production is summarised. Furthermore, the status of DBD plasma for catalyst synthesis and proposed future avenues to design environmentally suitable and cost-effective synthesis techniques are discussed. [Display omitted] • The NTP plasma techniques for catalyst synthesis is overviewed. • The DBD plasma-treated catalyst is summarised. • Prospects of DBD for catalyst synthesis in H 2 /syngas production is presented. [ABSTRACT FROM AUTHOR]

[Display omitted] • Investigation of surfactants on stability, rheology and thermophysical properties of Water-EG based Al 2 O 3 -TiO 2 hybrid nanofluids. • Al 2 O 3 -TiO 2 hybrid nanofluids exhibit Newtonian behavior. • Surfactants increase the stability but compromised the thermal conductivity. • PVP incorporated nanofluids are stable for 60 days with zeta potential value of 55.6 mV. • Viscosity and thermal conductivity enhancement by PVP was 50% and 3.6% at 80 °C respectively. This study investigates the influence of eight distinct surfactants on the stability, rheological characteristics, and thermophysical properties of hybrid nanofluids (NFs) containing Aluminum oxide (Al 2 O 3) and Titanium dioxide (TiO 2) in a Water-Ethylene Glycol (EG) mixture (60:40). The objective and novelty of this research is to choose the best surfactant for long run applications in terms of stability, viscosity and thermal conductivity. The results reveal that polyvinylpyrrolidone (PVP) exhibited the highest stability among all surfactants, surpassing others in zeta potential and visual stability over 60 days. Additionally, all the nanofluids exhibited Newtonian behavior. Surfactant addition increased viscosity, with polyethylene glycol (PEG) showing the highest enhancement of 37.2 % at 30 °C. Thermal conductivity increased with temperature, maximum TC enhancement of 8.3 % at 80 °C was given by PEG and oleic acid (OA), but these surfactants were unstable to be used in any application. In conclusion, PVP emerged as the most suitable surfactant for Al 2 O 3 -TiO 2 hybrid nanofluids due to its exceptional stability, moderate viscosity, and TC enhancement. It enhanced the TC by 3.6% at 80°C and contributed 28.9% in viscosity increment at 30°C. This research contributes to the understanding of surfactant effects on nanofluid properties, particularly highlighting PVP's potential for long-term heat transfer applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Investigation of surfactants on stability, rheology and thermophysical properties of Water-EG based Al 2 O 3 -TiO 2 hybrid nanofluids. • Al 2 O 3 -TiO 2 hybrid nanofluids exhibit Newtonian behavior. • Surfactants increase the stability but compromised the thermal conductivity. • PVP incorporated nanofluids are stable for 60 days with zeta potential value of 55.6 mV. • Viscosity and thermal conductivity enhancement by PVP was 50% and 3.6% at 80 °C respectively. This study investigates the influence of eight distinct surfactants on the stability, rheological characteristics, and thermophysical properties of hybrid nanofluids (NFs) containing Aluminum oxide (Al 2 O 3) and Titanium dioxide (TiO 2) in a Water-Ethylene Glycol (EG) mixture (60:40). The objective and novelty of this research is to choose the best surfactant for long run applications in terms of stability, viscosity and thermal conductivity. The results reveal that polyvinylpyrrolidone (PVP) exhibited the highest stability among all surfactants, surpassing others in zeta potential and visual stability over 60 days. Additionally, all the nanofluids exhibited Newtonian behavior. Surfactant addition increased viscosity, with polyethylene glycol (PEG) showing the highest enhancement of 37.2 % at 30 °C. Thermal conductivity increased with temperature, maximum TC enhancement of 8.3 % at 80 °C was given by PEG and oleic acid (OA), but these surfactants were unstable to be used in any application. In conclusion, PVP emerged as the most suitable surfactant for Al 2 O 3 -TiO 2 hybrid nanofluids due to its exceptional stability, moderate viscosity, and TC enhancement. It enhanced the TC by 3.6% at 80°C and contributed 28.9% in viscosity increment at 30°C. This research contributes to the understanding of surfactant effects on nanofluid properties, particularly highlighting PVP's potential for long-term heat transfer applications. [ABSTRACT FROM AUTHOR]

The performance of PV modules is significantly influenced by environmental factors, particularly soiling, which can be exacerbated by the presence of dew. This study aims to investigate the morphological changes caused by dew on dust and proposes a novel automated water-based cleaning system to remove dew-induced dust deposited on PV modules. The experiments were conducted under the climatic conditions of Islamabad, Pakistan, using poly-PV modules. The results revealed that the soiling losses at tilt angles of 23°, 33°, and 43° were 16.20%, 14.12%, and 11.64%, respectively. The newly proposed cleaning system utilizes flat fan nozzles to sprinkle water, and the power recovered after twenty days of effective cleaning was 12.07%, 11.40%, and 9.92% at tilt angles of 23°, 33°, and 43°, respectively. During the cleaning process, an average of 7.325 L of water was necessary to clean a surface area of 1.48 m2 of the solar PV module. Additionally, this cleaning procedure has a cooling effect on the PV modules, resulting in a reduction of the front surface temperature by 0.82 °C, 0.52 °C, and 0.45 °C at tilt angles of 23°, 33°, and 43°, respectively. The back surface temperature was also lowered by 1.2 °C, 0.74 °C, and 0.3 °C at the corresponding tilt angles. Furthermore, a financial evaluation of the proposed automatic cleaning system indicates its feasibility for both domestic and commercial-sized PV systems. [ABSTRACT FROM AUTHOR]

Ceramic materials are widely used as a photocatalyst due to their low cost synthesis, photostability, suitable bandgap and excellent photodegradation properties. One such material is TiO 2 however, it shows very low efficiency because it is only active in UV region (4 % of solar spectrum), have high holes-electrons recombination and low adsorption capacity. To address these limitations, highly active modified TiO 2 based ceramic materials like Er 2 O 3 /TiO 2, Molybdenum loaded TiO 2 and TiO 2 /Er 2 O 3 photocatalysts were synthesized by Sol-gel method. These synthesized photocatalysts were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, photoluminescence (PL) emission spectroscopy, UV–vis spectra, and Brunauer–Emmett–Teller (BET). The incorporation of Er 2 O 3 into TiO 2 and metal loading of molybdenum reduced the bandgap of TiO 2 from 3.3 eV to 3.25 eV, 3.1 eV, and 3.09 eV for TiO 2 –Er 2 O 3 , Mo loaded TiO 2 and Mo loaded TiO 2 –Er 2 O 3, respectively. BET analysis revealed the enhancement of surface area by adding Er 2 O 3 and Mo (from S BET = 39.9 m2/g to S BET = 67 m2/g) which is one of the crucial factors to increase the photocatalytic activity. The loading of molybdenum enhanced the immobilization of carriers that facilitated the photo-oxidation process and suppressed the electron-holes recombination (from 800 counts to 200 counts) as confirmed by the PL spectroscopy. The photocatalytic activity of these catalysts were evaluated by studying the photodegradation of Methylene blue (MB) under sunlight in standard conditions (1 sun, 1 atm). The synergistic effect of inclusion of Erbium Oxide and loading of molybdenum in titania-Erbium Oxide composite enhanced the photodegration efficiency from 13.2% to 75 %. The photocatalytic activities were in order of Mo@TiO 2 –Er 2 O 3 > Mo@TiO 2 > TiO 2 –Er 2 O 3 > TiO 2. These modifications also improved the conductivity of titania (σ = 4.43 × 10−4 Sm−1 to σ = 5.31 × 10−4 Sm−1) that was confirmed by Hall effect. These results supported the effectiveness of titania-modified composite for the degradation of industrial textile dye wastewater under sunlight and can be used for an optoelectronics applications. • TiO 2 ,TiO 2 –Er 2 O 3 ,Mo@TiO 2 and Mo@TiO 2 –Er 2 O 3 were investigated for photocatalytic degradation of harmful Textile dyes. • Mo@TiO 2 –Er 2 O 3 exbibits the highest photocatalyic activity on the merit of improved bandgap and increase in surface area. • Improvement in Hole-Electron pair recombination and transportation are responsible for enhanced activity. • Z-Scheme based Mechanism for improved Photocatalyic efficiency. [ABSTRACT FROM AUTHOR]

In this study, various energy conservation techniques and clean energy utilization prospects are investigated for the residential buildings of Saudi Arabia. A base case study of a distinctive residential building in Saudi Arabia is performed using simulation packages and its energy performance is optimized by incorporating the design standards of International Energy Conservation Code (IECC). The optimized results show that the energy consumed by the IECC standardized building is less by 56% for space cooling, 37% for space heating, 46% for lighting, and 27% for appliances. The IECC standardized building is integrated with a passive solar water heating system and a grid-connected solar PV system to meet the water heating load and lighting load, respectively. The use of solar water heating system shows 76% reduction in energy consumption as compared to the electric water heater. The feasibility of integrating a grid-connected solar PV system in the residential buildings is justified in terms of subsidy provided by the government and eco-environmental benefits. Finally, the prospects of utilizing solar energy in buildings are discussed with their economic and environmental benefits. [ABSTRACT FROM AUTHOR]

Various fillers such as zeolites, metal-organic framework, carbon, metal framework, graphene, and covalent organic framework have been incorporated into the polymers. However, these materials are facing issues such as incompatibility with the polymer matrix, which leads to the formation of non-selective voids and thus, reduces the gas separation properties. Recent studies show that hexagonal boron nitride (h-BN) possesses attractive characteristics such as high aspect ratio, good compatibility with polymer materials, enhanced gas barrier performance, and improved mechanical properties, which could make h-BN the potential candidate to replace conventional fillers. The synthesis of materials and membranes is the subject of this review, which focuses on recent developments and ongoing problems. Additionally, a summary of the mathematical models that were utilised to forecast how well polymer composites would perform in gas separation is provided. It was found in the previous studies that tortuosity is the governing factor for the determination of the effectiveness of a nanofiller as a gas barrier enhancer in polymer matrices. The shape of the nanofiller particles and sheets, disorientation and distribution of the nanofillers within the polymer matrix, state of aggregation and rate of reaggregation of the nanofiller particles, as well as the compatibility of the nanofiller with the polymer matrix all played a significant role in determining how well a particular nanofiller will perform in enhancing the gas barrier properties of the nanocomposites. For this purpose, this review has been focused not only on the experimentation work but also on the effect of tortuosity, exfoliation quality, compatibility, disorientation, and reaggregation of nanofillers. [Display omitted] • Experimental results acquired from h-BN based nanocomposites are summarized. • Mathematical models explaining the experimental results have been studied. • Recommendations are given to improve performance of gas barrier coatings. • Novel methods for environmental remediation are critically explained. [ABSTRACT FROM AUTHOR]

The massive increase in the use of PET plastic bottles has raised the challenge of accumulated waste plastics disposal and its related environmental concerns. Reusing this plastic waste through a solvent-based recycling process seems to be an eco-friendly solution for eliminating waste plastic and converting them into high quality products. The selection of solvent with its temperature requirement for the dissolution of polymeric materials is crucial in the solvent-based recycling process. Therefore, an innovative MATLAB program named HSPs-TPT was designed and constructed in this work to evaluate the dissolving power of solvents. Through this program, the solubility of the waste PET polymer was examined in thirteen (13) different solvents at different temperatures. As a results, the degree of waste PET polymer dissolution in the solvents was presented as the polymer-solvent solubility diagram, which provided the information about the relative energy difference (RED) change with the temperature rise. The program also provided the temperature range effective for the dissolution of PET by indicating the minimum and maximum solubility point for each solvent, which was further validated by the experimental data found in the literature. The proposed MATLAB program can numerically analyse the solubility of a polymer in different solvents in a short time for the recycling process and fabrication of different value-added plastic products such as polymer monoliths and membrane filters. [Display omitted] • The solubility of waste PET was examined in 13 solvents at different temperatures. • A MATLAB program for temperature based solubility analysis has been developed. • The RED changes with the temperature rise was studied for each solvent. • The temperature range for the PET dissolution for each solvent was determined. • The miscibility order at minima and maxima solubility points were discussed. [ABSTRACT FROM AUTHOR]

Co/TiO2–MgAl2O4 was investigated in a fixed bed reactor for the dry reforming of methane (DRM) process. Co/TiO2–MgAl2O4 was prepared by modified co-precipitation, followed by the hydrothermal method. The active metal Co was loaded via the wetness impregnation method. The prepared catalyst was characterized by XRD, SEM, TGA, and FTIR. The performance of Co/TiO2–MgAl2O4 for the DRM process was investigated in a reactor with a temperature of 750 °C, a feed ratio (CO2/CH4) of 1, a catalyst loading of 0.5 g, and a feed flow rate of 20 mL min−1. The effect of support interaction with metal and the composite were studied for catalytic activity, the composite showing significantly improved results. Moreover, among the tested Co loadings, 5 wt% Co over the TiO2–MgAl2O4 composite shows the best catalytic performance. The 5%Co/TiO2–MgAl2O4 improved the CH4 and CO2 conversion by up to 70% and 80%, respectively, while the selectivity of H2 and CO improved to 43% and 46.5%, respectively. The achieved H2/CO ratio of 0.9 was due to the excess amount of CO produced because of the higher conversion rate of CO2 and the surface carbon reaction with oxygen species. Furthermore, in a time on stream (TOS) test, the catalyst exhibited 75 h of stability with significant catalytic activity. Catalyst potential lies in catalyst stability and performance results, thus encouraging the further investigation and use of the catalyst for the long-run DRM process. [ABSTRACT FROM AUTHOR]

In this study, the current situation and future prospects of cleaner energy production through concentrated solar power (CSP) plants in Pakistan are analyzed. The assessment of required resources, evaluation of techno-economic feasibility, analysis of existing policy framework, and potential barriers in adopting the concentrated solar thermal technologies in Pakistan are presented. Six potential sites for installing solar thermal power plants are selected on the basis of solar resource assessment, land availability, and feasible infrastructure. A case study of a 100 MW parabolic trough collector (PTC) solar thermal power plant is simulated for these potential sites by using the System Advisor Model (SAM) software. The optimization of solar field size and thermal energy storage is performed to obtain the minimum Levelized cost of electricity (LCOE) for each potential site. Results indicate that the LCOE under the optimized configuration of the PTC solar thermal power plant in Pishin and Quetta can be minimized to 14.7 cents/kWh and 15.3 cents/kWh, respectively. Although the LCOE is the lowest in Pishin, the better availability of the desired infrastructure including transmission lines, water facility, and grid stations in Quetta makes it a more favorable site for installing the PTC solar thermal power plant. Furthermore, a discussion of government policies, along with major barriers (financial, political, infrastructural, technical, and social) that hinder the development of concentrated solar thermal technologies in Pakistan, is presented in detail. In order to overcome these barriers, several recommendations, including the introduction of financial incentives to investors, promoting private stakeholders, the establishment of research facilities in the country, and educating the general population regarding the benefits of clean energy are also outlined. • Potential and viability of CSP generation in Pakistan is evaluated. • Solar, infrastructural, and land resource assessment for CSP generation is presented. • Techno-economic evaluation of 100 MW PTC solar thermal power plant is performed. • Pishin and Quetta are techno-economically favorable regions for CSP generation. • Policy framework and potential barriers for CSP generation in Pakistan are presented. [ABSTRACT FROM AUTHOR]