Enhancement Of Efficiency Research Articles

UV-Resistant Nanostructured Anti-reflective Film for Achieving Efficiency Enhancement of Perovskite Solar Cells and Potential of Fabricating Large-Scale Cu(In, Ga)Se2 Solar Cells.

Sticker-type transparent antireflective film (STAF) is applied to perovskite solar cells (PSCs) to reduce the reflection and improve the light-trapping ability of PSCs. However, the development of STAF is hindered by many factors, such as expensive materials, low actual service life, unsatisfactory antireflective effect, and a lack of research on stability. This work proposes an ultraviolet (UV)-resistant enhanced sticker-type nanostructure acrylic resin antireflective film (SNAAF), which is applied to the incident surface of PSCs. SNAAF is prepared by using a cleverly designed two-step peeling transfer process. The average reflectance of the related device is reduced by 4.06% through the entire visible light spectrum, which also helps achieve the champion performance of the PSCs with STAF. The excellent antireflection performance increases power conversion efficiency (PCE) from 20.77% to 22.1% owing to the significantly enhanced short-circuit current density by 5.5% with the SNAAF. Additionally, the target device maintains nearly 80% of its initial PCE after 480 h of irradiation with UV light (365 nm), far exceeding the exposure levels in IEC 61215. Moreover, the designed SNAAF is applicable to large-area Cu(In, Ga)Se2 (CIGS) solar cells (area: 225 cm2), which develops a practical external engineering strategy for optimizing device performance for different types of commercial solar cells.

Research on the impact of the digital economy on carbon emissions based on the dual perspectives of carbon emission reduction and carbon efficiency

China’s digital economy is currently thriving, with the “dual carbon” targets representing a significant pursuit of economic development. The role of the digital economy in achieving these targets warrants detailed discussion. Using urban panel data from China spanning 2011 to 2021, this paper empirically examines the impact of the digital economy on urban carbon emissions. The findings reveal several key points: Firstly, the digital economy significantly reduces urban carbon emissions and enhances efficiency, a conclusion that remains valid after a series of robustness checks. Secondly, there is a notable structural effect, with different dimensions of the digital economy exhibiting varying impacts on urban emission reduction and efficiency enhancement. Thirdly, green economic efficiency and green technological innovation are crucial mechanisms through which the digital economy facilitates urban carbon emission reduction and efficiency improvement, operating through green development and innovation channels. Fourthly, industrial structure upgrading is a key nonlinear factor reducing the digital economy’s impact on carbon reduction, while the digital economy’s effect on urban carbon efficiency shows a U-shaped pattern. Lastly, the impact of the digital economy on urban carbon emissions displays significant heterogeneity across cities of different locations, tiers, and characteristics.

TiO2-Nanobelt-Enhanced, Phosphorescent, Organic Light-Emitting Diodes

This study investigates the enhancement of organic light-emitting diode (OLED) performance through the integration of titanium dioxide (TiO2) nanocomposites within a poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT/PSS) matrix. The nanocomposite films were prepared using a controlled dispersion of TiO2 belts into the PEDOT/PSS solution, followed by their incorporation into the OLED hole-injection layer (HIL). Our results demonstrate a significant improvement in device efficiency, attributed to the optimized charge carrier mobility and reduced recombination losses, which were achieved by the presence of TiO2. The nanocomposite hybrid layer enhances light emission efficiency due to its role in modifying surface roughness, promoting better film uniformity, and improving hole injection. The incorporation of TiO2 nanobelts into PEDOT/PSS led to significant efficiency enhancements, yielding a 39% increase in PEmax, a 37% improvement in CEmax, and a remarkable 72% rise in EQEmax compared to the undoped counterpart. This research provides insight into the potential of TiO2 nanocomposites in advancing OLED technology for next-generation display and lighting applications.

Enhancing seismic risk assessment through probabilistic analysis of liquefaction potential index: a computational intelligence approach

ABSTRACT This study proposes a novel computational intelligence approach for enhancing seismic risk assessment through probabilistic analysis of the liquefaction potential index (LPI). The methodology leverages a hybridised model that combines backpropagation neural networks (BcNN) with an improved firefly algorithm (IFF) to predict LPI values accurately and efficiently. The BcNN-IFF model was trained and validated using a comprehensive dataset comprising the geotechnical and seismic parameters from various earthquake-prone regions worldwide. Feature importance analysis revealed that total stress (σv’) and peak ground acceleration (amax) were the most influential factors in the LPI prediction. The BcNN-IFF model demonstrated superior performance compared to other hybrid models, achieving 91% accuracy in the training phase and 85% accuracy in the testing phase, with low root mean square error and mean absolute error values. The practical implications of the BcNN-IFF model highlights its potential for reliable liquefaction susceptibility assessments, particularly in resource-constrained environments. Future research directions are outlined, emphasising the need for uncertainty quantification, data augmentation, and computational efficiency enhancements to improve the applicability of the model in real-world scenarios. This study advances state-of-the-art computational modelling and provides a foundation for integrating such tools into geotechnical engineering practices for effective seismic risk assessment and infrastructure resilience.

Increasing the Market Value of Buildings Through Energy Retrofitting: A Comparison of Actual Retrofit Costs and Perceived Values

This study investigates how energy retrofitting measures contribute to increasing the market value of multi-family residential buildings within the European real estate market. It examines how energy efficiency improvements, driven by EU decarbonization strategies, enhance the actual and perceived value of these properties. The research employs a dual-methodology approach, integrating the Cost Approach to estimate the financial impact of retrofitting with the Contingent Valuation Method (CVM) to evaluate consumer willingness-to-pay (WTP) for energy-efficient properties. Two real case studies are considered to evaluate the methodology and how the monetary value of buildings is affected by their energy efficiency. The results revealed that buildings subjected to deep energy retrofitting are more attractive to potential buyers, who are willing to pay a premium of 13.5% over properties in pre-retrofit conditions. This underscores the tangible market value increment attributed to energy efficiency enhancements. This study bridges the gap between the quantifiable costs of energy retrofitting and the market valuation, offering a dual perspective by integrating both actual cost analysis and perceived market value. Moreover, this work highlights the correlation between energy retrofit investments and increased market value in the European real estate sector.

Enhancement of Light Extraction Efficiency in AlGaN‐Based Deep Ultraviolet Light‐Emitting Diodes Using Cooperative Scattering Structures on the n‐AlGaN Layer

AbstractThe efficiency of AlGaN based deep ultraviolet light‐emitting diode (DUV LEDs) are mainly hindered by the light extraction issue. In this work, an innovative cooperative scattering structure is introduced that combines a nanopore configuration with an aluminum (Al) nanoparticle array on the n‐AlGaN layer of the DUV LEDs. The integration of these two scattering arrays can enhance light extraction by mitigating total internal reflection at the device interface. The nanopores are formed on the n‐AlGaN surface by electrochemical etching and optimized by varying the etching voltage, while the Al particles are formed by thermal annealing. With the help of the cooperative scattering structure, the light output power (LOP) of the optimized DUV LEDs is significantly increased by 77.6% and a notable 2.2 times is achieved in its light extraction efficiency (LEE) enhancement factor. Moreover, Finite‐Difference Time‐Domain (FDTD) simulations have validated that the cooperative scattering structure considerably enhances the LEE for both Transverse Electric (TE) and Transverse Magnetic (TM) modes, respectively. This work paves the way to fabricate high efficiency DUV LEDs via novel scattering structure designs.

Improving the light extraction efficiency of white-light perovskite light-emitting diodes based on quantum dot nanowires

This study introduces an innovative strategy to enhance the light extraction efficiency (LEE) of white-light perovskite light-emitting diodes (PeLEDs) by incorporating quantum dot nanowires (QD-NWs) that are prepared by a porous anodic aluminum (PAA) substrate. The QD-NWs were synthesized through a combination of inkjet printing and vacuum deposition based on the PAA substrate which features a unique waveguiding structure that redirects post-color conversion fluorescence along its axis, effectively minimizing energy losses such as reabsorption loss and total internal reflection (TIR) loss. Empirical evidence indicates a significant luminance enhancement of 43.79%, accompanied by an enhancement in current efficiency, for PeLEDs incorporating the QD-NWs. By fine-tuning the structural attributes of the PAA substrate to regulate the size of QD-NWs, this research has successfully developed white-light PeLEDs based on quasi-2D blue perovskite, offering a universal strategy for boosting LEE and propelling the evolution of white-light PeLED technology.

Role of Solar Energy in Achieving Global Net-Zero Targets: Policy and Technological Perspective

Solar Energy Essential in Global Drive for Net Zero Emissions This paper sets out to address the complex role of solar power as an enabler for decarbonization, highlighting both policy and technology-related matters. We assess the effectiveness of different policy instruments in fostering solar energy uptake: financial incentives and regulatory frameworks that level the playing field with other technologies or curtail them by limiting, e.g., fossil fuel use, carbon pricing mechanisms, and international cooperation. We also review key technological advancements in photovoltaics, energy storage, and grid integration that are essential for solar energy to play an optimized role in a sustainable energy future. For these intents and purposes, we explore how new technologies such as perovskite solar cells (PSCs), concentrated solar power (CSP), or building-integrated photovoltaics (BIPV) could offer a significant enhancement of efficiency and dynamism in converting sunlight into electricity. Case We explore the dos and don’ts of being a perfect project through stories from successful solar energy integration projects. We assess the challenges and opportunities associated with solar powering in the future, underscoring the provision of cohesive policy as well as technology road-maps to achieve global net-zero targets. Our study underscores the potential of solar energy as a transformative resource. It provides direction to policy-makers, scholars, and industry actors regarding pathways that may accelerate the deployment of this increasingly vital renewable technology.

Physical and Chemical Preparation Techniques and Applications of Photonic Crystals: A Review

Photonic crystals, which are important functional materials, are formed by the periodic arrangement of materials with different dielectric constants that have photonic bandgaps and localization properties. Their preparation methods are primarily physical and chemical. Physical methods include mechanical drilling, layer-by-layer stacking, and precision processing. Chemical methods primarily involve colloidal self-assembly methods. Various colloidal crystal self-assembly methods have been reported, each with its own advantages and disadvantages. Photonic crystals have important applications in many fields, such as optical communications, information technology, energy, biomedicine, and sensors, including high-performance optical fiber fabrication, photonic chip development, and solar cell efficiency enhancement. This paper reviews the latest progress in the preparation of photonic crystals using physical and self-assembly methods. Currently, the preparation and application of photonic crystals have made significant achievements; however, there are still challenges in terms of preparation accuracy, efficiency, cost, and application integration technology. With the future development of science and technology, breakthroughs are expected in novel structural development, preparation process optimization, and cross-field integration, which will continue to promote the progress of photonic crystals and social development.

Heterogeneous influences of urban compactness on air pollution: evidence from 285 prefecture-level cities in China

Fine particulate matter (PM2.5) pollution can harm the climate, the environment, and human health. With sustainability initiatives receiving increasing attention, whether compact urban development can yield green environmental benefits has become an essential research proposition among urban planners. The compact city theory advocates energy efficiency enhancement through the mutual superposition of urban functions. First, a theoretical analysis framework for the effect of urban compactness on environmental quality was constructed. Second, on the basis of panel data from 285 prefecture-level cities in China from 2010 to 2021, exploratory spatial data analysis (ESDA) was applied to reveal the spatiotemporal nonstationary distribution of urban PM2.5 pollution. Finally, the heterogeneous influence mechanisms of compact urban factors on PM2.5 pollution were empirically studied through the geographical and temporal weighted regression (GTWR) model. The main findings are as follows: (1) From 2010 to 2021, the proportion of cities in China with good air quality significantly increased. The cities with high–high pollution clustering are currently located mainly in Beijing–Tianjin–Hebei, Shandong, and Henan. (2) Economic and transportation compactness factors mitigated PM2.5 pollution in most cities, whereas the long-term combined effects of the population and land compactness factors may have exacerbated urban PM2.5 pollution. (3) There was significant spatial and temporal heterogeneity in the effects of urban compactness factors on air pollution. Cities where land-use compactness exerts a pollution mitigation effect were located east of the Hu line. Cities in Northeastern China had the strongest pollution mitigation effect from transportation compactness, followed by the cities in Southwestern China.

International Crestonomy

International Crestonomy provides an innovative theoretical and practical framework regarding the enhancement of efficiency and utility in global cooperation. In this dynamic and complex world, where all international relations take place, International Crestonomy emerges as a particularly important concept, as it brings together all the principles and mechanisms for optimizing efficiency and utility in this field and, consequently, the concept becomes essential for ensuring global peace, stability, and prosperity. The objectives of International Crestonomy, which we aim to highlight in this article, are: defining and understanding the concept of International Crestonomy; identifying the fundamental principles of International Crestonomy; analyzing the challenges and perspectives of International Crestonomy and developing methods and mechanisms for optimizing efficiency and utility.

Entangled quantum Stirling heat engine based on two particles Heisenberg model with Dzyaloshinskii-Moriya interaction

Quantum heat engines have attracted significant attention in recent years due to their potential to surpass classical thermodynamic limits by leveraging quantum effects such as entanglement and coherence. In this study, we analyze a quantum Stirling heat engine characterized by a working substance composed of a two-particle Heisenberg model with Dzyaloshinskii–Moriya (DM) interaction under an external magnetic field. We investigate the impact of the antisymmetric interaction on the engine’s efficiency across varying coupling parameters. Our findings demonstrate that the utilization of a two-qubit Heisenberg model in an entangled quantum Stirling heat engine can significantly enhance efficiency and performance. By optimizing the antisymmetric exchange parameters, we achieve substantial enhancements in engine efficiency, with results demonstrating that the efficiency attains remarkably high values compared to other cycles utilizing the same working substance. These enhancements are primarily influenced by the DM interaction and the entangled states of the working substance, leading to superior performance.

Significant Efficiency Enhancements in Non-Y Series Acceptors by the Addition of Outer Side Chains.

Most current highly efficient organic solar cells utilize small molecules like Y6 and its derivatives as electron acceptors in the photoactive layer. In this work, a small molecule acceptor, SC8-IT4F, is developed through outer side chain engineering on the terminal thiophene of a conjugated 6,12-dihydro-dithienoindeno[2,3-d:2',3'-d']-s-indaceno[1,2-b:5,6-b']dithiophene (IDTT) central core. Compared to the reference molecule C8-IT4F, which lacks outer side chains, SC8-IT4F displays notable differences in molecule geometry (as shown by simulations), thermal behavior, single-crystal packing, and film morphology. Blend films of SC8-IT4F and the polymer donor PM6 exhibit larger carrier mobilities, longer carrier lifetimes, and reduced recombination compared to C8-IT4F, resulting in improved device performance. Binary photovoltaic devices based on the PM6:SC8-IT4F films reveal an optimal efficiency over 15%, which is one of the best values for non-Y type small molecule acceptors (SMAs). The resultant devices also show better thermal and operational stability than the control PM6:L8-BO devices. SC8-IT4F and its blend exhibit a higher relative degree of crystallinity and π coherence length, compared to C8-IT4F samples, beneficial for charge transport and device performance. The results indicate that outer side chain engineering on existing small electron acceptors can be a promising molecular design strategy for further pursuing high-performance organic solar cells.

Energy Performance Study of a Data Center Combined Cooling System Integrated with Heat Storage and Waste Heat Recovery System

The energy efficiency of data centers has become an urgent problem as it is enjoying rapid development. This study proposes an integrated energy system involving a data center with different renewable energy sources and waste heat recovery, which can consider the partial and unsteady working load of data center. A dynamic and sophisticated system simulation model is established, which can provide both reliable and fast evaluations but also allow flexible extension of additional components. It is found that the free natural resource cooling system can cover about 28% of cooling demand. Compared to the reference condition, the proposed energy system achieves significant energy-saving benefits, with an energy-saving rate of 16.4%. The system COP increases from 3.88 to 4.64, and the PUE decreases from 1.36 to 1.30, resulting in a 23.45% reduction in electricity expenses. By integrating a waste heat recovery system, the heat pump can absorb approximately 3.57 million kWh of heat from the data center, providing approximately 4.587 million kWh of heating energy for users. The rooftop PV system generates approximately 370,000 kWh of electricity annually, covering approximately 8% of the total electricity consumption of the data center. This study can offer a new channel for the energy efficiency enhancement of data centers.

Simultaneous enhancement of efficiency, stability and stretchability in binary polymer solar cells with a three-dimensional aromatic-core tethered tetrameric acceptor

Simultaneous enhancement of efficiency, stability and stretchability in binary polymer solar cells with a three-dimensional aromatic-core tethered tetrameric acceptor

Effect of Eight-Week Transcranial Direct-Current Stimulation Combined with Lat Pull-Down Resistance Training on Improving Pull-Up Performance for Male College Students.

The aim of this study was to investigate the effects and potential mechanisms of 8-week transcranial direct-current stimulation (tDCS) combined with resistance training (RT) on pull-up performance in male college students. Twenty-five male college students were randomly assigned to either RT combined with anodal tDCS stimulation (RT + tDCS) or RT alone (RT). Participants of both groups engaged in lat pull-down training programs for 8 weeks, with the RT + tDCS group receiving 20 min tDCS before each RT session. Pre- and post-intervention tests included pull-up endurance (number of repetitions), flexed arm circumference (FAC), and lat pull-down maximal voluntary isometric contraction (MVIC) peak force. During the pull-up endurance test, surface electromyography (sEMG) was recorded for the bicep brachii (BB), tricep brachii (TB), brachioradialis (BR), anterior deltoid (AD), middle deltoid (MD), posterior deltoid (PD), pectoralis major (PM), and latissimus dorsi (LD) muscles. Both groups demonstrated significant improvements in pull-up endurance and lat pull-down MVIC peak force after training, but no significant difference between the two groups was observed in the post-training test. Additionally, muscle activation of BR, PD, and PM decreased significantly in both groups, while the RT + tDCS group also demonstrated a significant reduction in TB coactivation after training. These findings suggest that eight weeks of tDCS combined with lat pull-down training and lat pull-down training alone can both significantly improve pull-up performance, which may be attributed to enhanced muscle contraction capacity. Although no significant training gains were found between the two training groups, the RT + tDCS group showed a significant decrease in TB coactivation and the enhancement of elbow flexion muscle contraction efficiency after training.

Experimental Studies of Enhancing Solar Collector Efficiency by using a Storage Tank Containing Water Pipes and PCM

Thermal energy storage is a crucial process for retaining heat for future use. This experimental study investigates the integration of a storage tank containing water pipes and phase change materials (PCM) with a solar collector system. By employing paraffin wax (RT-42) as the PCM and leveraging its latent heat storage properties, the enhancement of thermal efficiency and energy storage capabilities in the evacuated tube solar collector is evaluated. Experiments were conducted under varying solar radiation intensity and ambient temperatures in winter and summer conditions. A solar collector and heater were tested for efficiency during winter and summer. The collector was installed at 45.5°S and heated with 120 litres of water. The system's efficiency was enhanced with increased solar radiation and flow rates. The thermal charging of the system took place between 8:00 am and 4:00 pm. The results showed longer hot water supply times at 4 L/m. The effect of adding PCMs and water pipes to solar collector systems was investigated, revealing significant improvements in thermal performance and energy storage. The findings showed an enhancement in temperature stability, with peak temperatures reaching 60°C in winter and 75°C in summer at flow rates of 4, 6, and 8 L/m. Using a storage tank, hot water pipes and PCM, especially paraffin wax, with a latent heat of fusion of 174 kJ/kg improved energy retention and hot water supply. The experiment outcomes showed that the summer hot water supply was twice as high as the winter hot water supply. The study also highlights the importance of improving flow rates to absorb and retain heat efficiently. Overall, the combination of PCM and water pipes enhanced the system efficiency and increased the availability of thermal energy.

CFD Analysis of Thermal Conditions and Airflow Patterns in Commercial Laundry Facility using ANSYS Fluent Simulation

This study investigates thermal conditions optimization in a commercial laundry facility through Computational Fluid Dynamics (CFD) analysis using ANSYS Fluent. The research was conducted at Commercial Laundry X in Batu Pahat, Johor, Malaysia, employing a methodology that integrated experimental measurements with computational modelling. Using advanced instrumentation including Temp Sensor T310, Temp Data Logger H100, Thermal Camera T640, and The VelociCalc Multi-Function Ventilation Meter (Model 9565), the study collected empirical data across strategically positioned sampling locations. The data collected from the equipment and instrumentation were compared with the temperature contours and velocity streamlines generated by the computational model. The validated computational model, exhibiting relative errors consistently below 10%, with lowest relative error of 2.17%, successfully simulated complex airflow patterns and temperature distributions throughout the facility. The thermal analysis revealed that of the facility's operational areas exceeded recommended comfort temperatures (23°C - 27°C), with the most significant hotspot reaching 37.81°C near dryer units. This thermal concentration was primarily attributed to the combined effect of equipment heat generation and insufficient thermal dissipation, resulting in localized high-temperature zones that significantly impact the working environment. These findings highlight the critical influence of heat-intensive operations on the thermal environment, indicating poor temperature uniformity and inadequate dissipation of heat in these areas. This research focuses on developing a 3D model of a commercial laundry facility, incorporating geometric and operational characteristics. The model is validated by comparing computational results with experimental measurements of temperature contours and velocity profiles. The study provides valuable insights for optimizing ventilation strategies and equipment placement in commercial laundry facilities, contributing to the enhancement of worker comfort and operational efficiency.

Scalable, Flexible, and UV-Resistant Bacterial Cellulose Composite Film for Daytime Radiative Cooling.

Radiative cooling, a passive cooling technology, functions by reflecting the majority of solar radiation (within the solar spectrum of 0.3-2.5 μm) and emitting thermal radiation (within the atmospheric windows of 8-13 μm and 16-20 μm). Predominantly, synthetic polymers are effectively utilized for radiative cooling while posing potential environmental hazards due to their complex components, toxicity, or nonbiodegradation. Bacterial cellulose, a natural and renewable biopolymer, stands out due to its environmentally friendly, scalability, high purity, and significant infrared emissivity. In this work, we developed a bacterial cellulose-based composite film (BCF) with a cross-linked network structure by a facile agitation spraying method to achieve enhanced and sustainable radiative cooling performance. The BCF exhibited superior optical properties and environmental tolerance, with a notable infrared emissivity of 94.6%. As a result, the thermal emitter demonstrates a substantial subambient cooling capacity (11:00 to 13:00, maximum drop of 7.15 °C, average drop of 4.85 °C; 22:00 to 2:00, maximum drop of 2.7 °C, average drop of 2.32 °C). Additionally, the BCF maintained stable emissivity after 240 h of continuous UV irradiation. Furthermore, BCF can effectively preserve the freshness of fruits under intense solar irradiation. Hence, BCF with high radiative cooling performance presents a broad application prospect in building energy conservation, solar cells efficiency enhancement, and food transportation packaging.

Optimizing Solar Power: The Impact of N719 Dye Concentration on DSSC Efficiency with TiO2 Nanoparticles

Dye-sensitized solar cells (DSSC) are photoelectrochemical, alternative energy source devices that convert light energy into electricity. In this study, DSSC with various concentrations (0.1, 0.5, and 1.0 mM) of N719 dye have been successfully prepared using simple steps. The X-ray diffraction results of the TiO2 film showed that it is polycrystalline with an anatase phase (tetragonal system) having a crystallite size of about 20 nm. The absorbance spectrum of the TiO2 film and N719 dye at various concentrations was recorded by ultraviolet-visible (UV-Vis) spectrophotometer. The bandgap energy of the TiO2 film calculated by Tauc’s formula was ~3.1 eV. The DSSC prepared using the N719 dye concentration of 1 mM achieved the highest conversion efficiency (η) of 0.298 %, respectively. Subsequently, the enhancement in efficiency was ~86 % compared with the conversion efficiency of DSSC prepared with an N719 dye concentration of 0.1 and 0.5 mM.