Fill Factor Research Articles

Iron-irradiated methylammonium lead iodide bromide (MAPbI2Br) thin films with enhanced optical and electrical properties for high-efficiency perovskite solar cells

In the pursuit of enhancing the optoelectronic properties of perovskite thin films for photovoltaic applications, this study investigates the effects of Fe ion irradiation on methylammonium lead iodide bromide (MAPbI₂Br) thin films. Thin films of methylammonium lead iodide bromide, (CH3NH3PbI2Br, or MAPbI2Br) have been deposited by sol–gel dip coating technique. These films were irradiated with 300 keV Fe ions with flouncy of 2 × 1014 ions/cm2. The prepared films all show the cubic crystal structure. However, the film irradiated with Fe ions has a larger grain size, according to XRD. The optical characteristics, such as refractive index, band gap energy, and extinction coefficients, are examined by UV–Vis analysis. Although both the films showed a direct bandgap, the film irradiated with Fe ions showed a lower value for the bandgap energy (1.76 eV) and high refractive index. The device structure used was FTO/TiO2/MAPbI2Br/spiro-OMeTAD/Au. The devices made with 300 keV Fe ions irradiated film has high current density of 10.86 mA cm−2, fill factor of 0.80, an open circuit voltage of 1.06 V, and an efficiency of 9.93%. The findings emphasize the potential of Fe ion irradiation as a novel technique to improve grain structure and optoelectronic properties, advancing perovskite-based device technology for higher efficiency solar cells.

Small-Molecule Hole Transport Materials for >26% Efficient Inverted Perovskite Solar Cells.

Chemically modifiable small-molecule hole transport materials (HTMs) hold promise for achieving efficient and scalable perovskite solar cells (PSCs). Compared to emerging self-assembled monolayers, small-molecule HTMs are more reliable in terms of large-area deposition and long-term operational stability. However, current small-molecule HTMs in inverted PSCs lack efficient molecular designs that balance both the charge transport capability and interface compatibility, resulting in a long-standing stagnation of power conversion efficiency (PCE) below 24.5%. Here, we report the comprehensive design of HTMs' backbone and functional groups, which optimizes a simple planar linear molecular backbone with a high mobility exceeding 7.1 × 10-4 cm2 V-1 S-1 and enhances its interface anchoring capability. Owing to the improved surface properties and anchoring effects, the tailored HTMs enhance the interface contact at the HTM/perovskite heterojunction, minimizing nonradiative recombination and transport loss and leading to a high fill factor of 86.1%. Our work has overcome the persistent efficiency bottleneck for small-molecule HTMs, particularly for large-area devices. Consequently, the resultant PSCs exhibit PCEs of 26.1% (25.7% certified) for a 0.068 cm2 device and 24.7% (24.4% certified) for a 1.008 cm2 device, representing the highest PCE for small-molecule HTMs in inverted PSCs.

Nanostructured bismuth chloride based ((CH3NH3)3Bi2IxCl9-x) active layers for lead-free perovskite solar cells

Abstract Bismuth is one of the promising elements that can replace toxic lead in perovskite solar cells. However, surface roughness and inhomogeneous morphology with voids on the bismuth perovskite films limits their photovoltaic performance. In the present work, a scalable doctor-blade technique is employed to prepare perovskite thin film with high surface coverage. Methylammonium bismuth halide (MABiH) ((CH3NH3)3Bi2ClxI9-x) nanoparticles were synthesized by conventional sol-gel technique. The formation of perovskite structure was confirmed by X-ray diffraction measurement which confirmed that MABiH perovskite films were in hexagonal symmetry with polycrystalline nature. The prepared perovskite nanoparticles were deposited on mesoporous TiO2-coated FTO substrates through the spin coating technique and doctor blade method. Morphology analysis of MABiH perovskite revealed the formation of an orange Lily-like structure with higher surface coverage. Lead-free mesoporous perovskite solar cells prepared using MABiH perovskite material with carbon as hole extraction layer showed a maximum power conversion efficiency (PCE) of 0.004 %, with short circuit current density of 89 μA/cm2, open circuit voltage of 0.12 V and fill factor of 38 %. These results allow us to step toward fabricating bulk MABiH lead-free perovskite solar cells.

Efficiency enhancement of WSe2/In2S3 solar cell by numerical modeling using SCAPS

Tungsten diselenide (WSe2), a transition metal dichalcogenide (TMDC) compound, is considered a promising material for application in thin film solar cells because of its high carrier transport, tunable band gap, and high absorption coefficient. In this work, solar cell structure comprising FTO/In2S3/WSe2 is modeled using one-dimensional solar cell capacitance simulator (SCAPS-1D) software where wide bandgap widely accessible In2S3 is used as a novel buffer layer instead of toxic CdS buffer layer for WSe2-based solar cell. The effect of thickness, doping concentrations, defect density, radiative recombination coefficient, and the electron and hole capture cross-section are analyzed and optimized. After optimizing the device, the effect of operating temperature, shunt and series resistance and back contact work function are also investigated. At an optimized WSe2 absorber layer thickness of 1.5 µm and acceptor density of 1017 cm−3, efficiency of 22.53%, fill factor of 84.98%, open circuit voltage of 1.096 V, and short circuit current density of 24.18 mA/cm2 was obtained. Additionally, a back surface field (BSF) layer comprising amorphous silicon (a-Si) of thickness 0.05 µm is introduced between the absorber layer and the back contact to lessen carrier recombination at the back surface. Therefore, the efficiency rises from 22.53% to 29.5% with a fill factor of 89.53%, open circuit voltage of 1.26 V, and short circuit current density of 26.23 mA/cm2. The simulation results suggest that WSe2-based thin-film solar cells can be designed and fabricated with high efficiency and cost advantage.

Efficiency Assessment of GaInp/GaAs Tandem Solar Cells: Analytical Investigation and Numerical Simulation

This paper presents a numerical simulation of a dual-junction tandem GaInp/GaAs cell made from top GaInp and bottom GaAs cells. For this purpose, we utilized a numerical simulation tool. Two methodologies were proposed, the first method consists of simulating each base layer cell of the top and bottom separately, and the second method simulated both layers in one file, to simulate both in one file. For improved electric characteristics of tandem solar cells, the current-match requirement between the top and bottom cells should be satisfied, necessitating the careful design of parameters. The top base GaInp layer thickness is adjusted to match this requirement. The solar spectrum reaching the lower cell is analytically calculated by subtracting the top cell spectrum from the total spectrum. the optimal value of short current density corresponds with a top cell base thickness of 0.8 µm, this results in an open circuit voltage of 2.45 V, a short circuit current of 15.7 Am/cm2, a fill factor of 91 %, an efficiency of 35 % for the first method and the second method used a script file designed to verify the above results and confirmed the values to be; 2.68 V open circuit voltage, 15.26 Am/cm², a short circuit current, 90 % fill factor, and 36.86 % efficiency under AM 1.5 G solar spectrum.

Fluorination Strategy for Benzimidazole Core Based Electron Acceptors Achieving over 19% Efficiency for Ternary Organic Solar Cells.

The expansion of two-dimensional conjugated systems in nonfullerene electron acceptors (NFAs) has significantly advanced the molecular design and efficiency potential of organic solar cells (OSCs). This study introduces a novel class of NFAs featuring a benzimidazole core with varying degrees of peripheral fluorination, designated as YIS-4F, YIS-6F, and YIS-8F, respectively. Through systematic modulation of fluorine content, we observed that OSCs incorporating YIS-6F achieved the highest power conversion efficiency (PCE) of 17.28%, surpassing those with YIS-4F and YIS-8F. Notably, the incorporation of YIS-6F in a ternary blend with D18/N3 yielded a remarkable PCE of 19.43%. The enhanced performance of YIS-6F-based devices is attributed to the optimized energy level alignment and optimized crystallinity, which collectively facilitate efficient exciton dissociation, accelerated charge transport, and minimized charge recombination, culminating in an exceptional fill factor and PCE. Our findings underscore the pivotal role of fluorination of NFAs at the central benzimidazole core in optimizing molecular packing, and consequently enhancing the performance of OSCs.

One‐Pot Synthesis of Conjugation‐Extended Isomeric Dimer Acceptors for High‐Performance Q‑PHJ Solar Cells

AbstractEnd group modification is a crucial strategy for fine‐tuning non‐fullerene acceptors in organic solar cells (OSCs). Extending the conjugation of end groups enhances electron delocalization, promotes tighter intermolecular stacking, and improves crystallinity and spectral absorption. In this study, a series of isomeric dimer acceptors with conjugation‐extended end groups is synthesized to investigate how the position of end group extension affects the performance of dimers. Using a one‐pot Still coupling method, three dimers with inner end group extensions are efficiently synthesized, significantly reducing synthesis time and cost. Among these, the device based on dBSeIC‐ɛNIC exhibited a higher power conversion efficiency (PCE) compared to the dBSeIC‐γIC device, which lacks conjugated extension. Building on this, the connection site of the inner end group is optimized and extended the conjugation from the outer end group. As a result, the Q‐PHJ device using dBSeNIC‐γIC/PBQx‐H‐TF achieved a maximum PCE of 17.68%, largely due to a notable increase in fill factor (FF). The study reveals the critical impact of end group conjugation extension on dimer acceptor performance and underscores the importance of selecting the optimal connection site for enhancing OSC efficiency.

Chiral Steric Effect for Improved Phase Transition and Exciton Dynamics in Efficient and Stable All‐Polymer Solar Cells

AbstractChiral materials exhibit distinctive properties that improve the performance of organic solar cells (OSCs). In this study, chiral PM6 is integrated into PM6:PY‐IT blends to fabricate chiral quasi‐binary OSCs (cOSCs). The produced devices displayed an increased short‐circuit current and fill factor, achieving a peak efficiency of 16.60% compared to 15.96% for the standard PM6:PY‐IT cell. Additionally, the incorporation of chiral PM6 significantly enhanced the thermal stability, with the cOSCs retaining over 80% of their initial efficiency after 1000 h of operation. The steric effect of chiral PM6 altered the molecular packing, thereby improving the overall crystallinity. The optimized nanoscale domain morphology resulted in a more effective blend film, leading to superior device performance. Moreover, the chirality‐induced orbital angular momentum increased the ratio of triplet states, which is a key factor for increasing the photocurrent in OSCs. The delocalization of electron wavefunctions is driven by chiral steric effects, and it diminished the Coulomb attraction between the interfacial electron–hole pairs, which enhanced the efficient charge generation. This study provides valuable insights into the role of chirality in optimizing both the performance and stability of OSCs.

Dual Additive Strategy with Quasi-Planar Heterojunction Architecture Assisted in Morphology Optimization for High-Efficiency Organic Solar Cells.

Achieving high-performance and stable organic solar cells (OSCs) remains a critical challenge, primarily due to the precise optimization required for active layer morphology. Herein, this work reports a dual additive strategy using 3,5-dichlorobromobenzene (DCBB) and 1,8-diiodooctane (DIO) to optimize the morphology of both bulk-heterojunction (BHJ) and quasi-planar heterojunction (Q-PHJ) based on donor D18 and acceptor BTP-eC9. The systematic results reveal that the dual additive strategy significantly promotes phase separation while inhibiting excessive aggregation, which, in turn, improves molecular order and crystallization. As a result, BHJ and Q-PHJ OSCs processed with dual additive DIO + DCBB achieve impressive power conversion efficiencies of 17.77% and 18.60%, respectively, the highest reported values for dual additive-processed OSCs. The superior performance is attributed to improved charge transport and reduced recombination losses, as evidenced by higher short-circuit current densities (JSC) and fill factors (FF). Importantly, Q-PHJ OSCs processed with either DCBB or DIO + DCBB, in comparison to BHJ OSCs, exhibit exceptional shelf-stability, maintaining 80% of their initial power conversion efficiency after 2660 and 2193 h, respectively. These findings underscore the potential of dual additive strategies to advance the development of stable, high-efficiency OSCs suitable for large-area fabrication, marking a significant step forward in renewable energy technology.

Li, Ag Co‐Doping Enables Efficient Kesterite Solar Cell with a High Fill Factor of 74.30%

AbstractIn addition to open‐circuit voltage (VOC) loss, fill factor (FF) loss is considered another major factor restricting the further optimization of Cu2ZnSn(S,Se)4 (CZTSSe) device efficiency. In this work, a comprehensive investigation into the loss mechanisms of FF has been conducted, and implemented a Li&Ag co‐doping approach to enhance FF. The results indicate that the FF loss caused by insufficient carrier extraction is higher than that caused by non‐radiative recombination. The carrier extraction capability is significantly influenced by the band alignment of the CdS/CZTSSe interface and has little relationship with the carrier concentration of the absorber. Therefore, although Ag doping reduces the hole concentration and conductivity, it reduces the FF loss caused by carrier extraction due to the improvement of band alignment. Ag doping is also superior to Li in passivating harmful defects, which helps reduce FF losses caused by non‐radiative recombination. Correspondingly, Li performs better than Ag in increasing the hole carrier concentration and optimizing band alignment, greatly reducing FF losses caused by insufficient carrier transport. Finally, the Li and Ag co‐doping strategy enables a 14.91% efficient kesterite solar cell with the highest reported FF to date of 74.30% through collaborative optimization of carrier extraction and suppression of non‐radiative recombination.

High Efficiency (>10%) AgBiS2 Colloidal Nanocrystal Solar Cells with Diketopyrrolopyrrole-Based Polymer Hole Transport Layer.

Silver bismuth disulfide (AgBiS2) colloidal nanocrystals (CNCs) have emerged as ecofriendly photoactive materials with excellent photoconductivity and high absorption coefficients, in compliance with the restriction of hazardous substances (RoHS) guidelines. To maximize the theoretical potential of AgBiS2 CNC solar cells, a new diketopyrrolopyrrole (DPP)-based polymer, BD2FCT, optimized as a hole transport layer (HTL), is developed. This asymmetric thiophene-rich polymer HTL effectively complements the optical absorption spectrum of CNCs and forms a homogeneous layer atop the CNCs, facilitating favorable vertical charge transfer through intrinsic molecular packing. Furthermore, the BD2FCT HTL aligns energetically with AgBiS2, significantly reducing charge recombination at the CNC/HTL interfaces and enhancing charge extraction and photocurrent generation across the entire optical absorption spectrum. These characteristics are further optimized through precise molecular engineering. Additionally, a low-bandgap acceptor, IEICO-4F, is structurally incorporated with the BD2FCT polymer to further improve charge funneling and complementary absorption. Transient absorption spectroscopy reveals enhanced hole transfer from CNC to BD2FCT-29DPP:IEICO-4F, resulting in reduced charge recombination and efficient charge extraction. Consequently, a BD2FCT-based AgBiS2 CNC solar cell achieves a power conversion efficiency (PCE) of 10.1%, demonstrating significant improvements in short-circuit current density (JSC) and fill factor (FF).

Advancing all-polymer solar cells with solid additives

AbstractAll-polymer solar cells (all-PSCs) have attracted significant research attention in recent years, primarily due to their advantages of outstanding photo-thermal stability and excellent mechanical flexibility. However, all-PSCs typically exhibit complex morphologies during the film formation of blend films, primarily due to the tendency to become entangled in polymer chains, negatively impacting their fill factor (FF) and morphology stability. Therefore, the optimization of the morphology of the co-mingled heterojunction is crucial for improving device performance. Recent studies reveal that solid additives (SAs) can realize the excellent regulation of the molecular aggregation state, molecular packing, and domain size of the active layer, which not only improves the exciton dissociation, charge transport and collection process of the device but also ultimately realizes the enhancement of the device efficiency. Therefore, this review provides an in-depth insight into the different mechanisms of solid additives in all-PSCs, offering a comprehensive discussion on the research progress in optimizing the morphology and enhancing morphology stability. Finally, we present an outlook for the further structural modification strategies of solid additives towards better bulk morphology and stability of all-PSCs, paving the way for achieving excellent photo-thermal stability, superior mechanical flexibility, and high-efficiency all-PSCs.

Optimizing electrical properties and efficiency of copper-doped CdS and CdTe solar cells through advanced ETL and HTL integration: a comprehensive experimental and numerical study

Abstract Copper is a commonly preferred dopant for cadmium telluride based solar cells. Even though it is widely used as it enhances the electrical properties, it has the tendency to diffuse into the CdTe layer as well as the CdS/CdTe junction interface which adversely affects the performance of CdTe solar cells. In this experimental study copper doping of buffer cadmium sulfide layer has been performed to analyse its effect on structural, electrical, and optical properties of CdS and CdTe layers. While from the X-ray diffraction analysis it was observed that there was reduction in peak intensities and crystallite sizes of both the CdS and CdTe layers with the increase in amount of copper dopant, from the electrical properties it was found that there were improvements in carrier concentration, mobility, and conductivity of both the layers. To mitigate the losses due to Cu doping, enhance the efficiency and stability of CdTe solar cells an extensive numerical modelling approach was undertaken to employ electron transport layers (ETL) and hole transport layers (HTL) to the copper-doped CdS/CdTe solar cells. We obtained optimum results with titanium dioxide and copper barium thiostannate as ETL and HTL respectively. Finally, CdTe-based solar cells were modelled integrating copper-doped CdS as the buffer layers, TiO2 as ETL and CBTS as HTL respectively. The obtained experimental values of Cu-doped CdS and CdTe layers were implemented into this model. This superstrate configuration yielded impressive output parameters: open circuit voltage of 1.07 V, short-circuit current density of 29.32 mA cm−2, fill factor of 85.08 %, and efficiency of 26.67 %.

Studying the effects of temperature on InGaP/InGaAs/Ge triple junction solar cells using PyAMS Software

Multi-junction solar cells, particularly those utilizing III–V semiconductor materials, offer high conversion efficiency by employing multiple P-N junctions with different band gap energies to capture specific wavelengths of sunlight. Among these, the triple-junction photovoltaic cell, comprising Indium Gallium Phosphide (InGaP), Indium Gallium Arsenide (InGaAs), and Germanium (Ge) subcells, stands out for its efficiency. However, temperature variations significantly impact the performance of these subcells, necessitating a comprehensive understanding of their thermal behavior. In this study, we employ PyAMS (Python for Analog and Mixed Signals) software to model and simulate the behavior of InGaP/InGaAs/Ge sub cells under varying temperature conditions. Through comparison with experimental data, we validate our model and analyze key performance parameters, including short circuit current density (Jsc), open circuit voltage (Voc), fill factor (FF), and overall efficiency (η). Our findings reveal minimal changes in short circuit current density with temperature, while the open circuit voltage exhibits a substantial decrease beyond 60°C when exposed to concentrated illumination of 10 Suns, significantly impacting fill factor and efficiency. By elucidating the thermal behavior of three-junction solar cells, our study contributes valuable insights for designing and implementing cooling systems, thereby enhancing the performance and reliability of photovoltaic systems in practical applications.

Correlation between spin-dependent recombination centers and long-lived polarons generated in organic photovoltaic devices revealed by successive ESR and EDMR measurements

Using a successive detection technique with electron spin resonance (ESR) and electrically detected magnetic resonance (EDMR), this study clarifies the quantitative correlation between photoinduced spin amounts and spin-dependent recombination (SDR) currents in organic photovoltaic devices (OPVs). Using this unique method of sequentially switching between ESR and EDMR measurements under light irradiation, we find that the intensities of light-induced ESR and EDMR spectra increase along with the light irradiation power. Although positive correlation exists between the number of photo-generated radicals and the SDR currents, the relation is not proportional, which demonstrates that most of the photo-generated radicals are residual accumulated charges. Additionally, phases of the EDMR spectra under light irradiation were found to be changed because of a delay of modulated EDMR signals. The phase variation is probably caused by recombination centers: positive polarons that have arrived at the interface between an aluminum electrode and an active layer by charge drifting after charge separation. Because positive polarons are expected to transport positive charges to the opposite-side electrode of the aluminum as a negative charge collector, this leakage current can be a factor of disturbing an optimal charge collection. This combined technique of ESR and EDMR is useful to explore the different roles of polarons in the photovoltaic conversion processes, thereby providing important information for improving the fill factors and open-circuit voltages of the OPVs, which generate long-lived polarons.

Impact of Temperature on the Efficiency of Monocrystalline and Polycrystalline Photovoltaic Panels: A Comprehensive Experimental Analysis for Sustainable Energy Solutions

The negative effect of the operating temperature on the functioning of photovoltaic panels has become a significant issue in the actual energetic context and has been studied intensively during the last decade. The very high operating temperatures of the photovoltaic panels, even for lower levels of solar radiation, determine a drop in the open-circuit voltage, with consequences over the electrical power generated and PV-conversion efficiency. The temperature effect over the efficiency of monocrystalline and polycrystalline photovoltaic panels by using a double-climatic chamber and a solar simulation device was studied experimentally for two photovoltaic panels, one monocrystalline and another polycrystalline, with the same nominal power of 30 Wp. The double-climatic chamber used is composed of two separate rooms, a cold and a hot one, while the PV panel is placed as a barrier between them. The study is focused on establishing the effect of raising the temperature of PV panels over electrical parameters: voltage, current, and power produced and for efficiency and fill factor to promote sustainable energy consumption. The findings highlight the positive impact of cooling on enhancing system efficiency, with the primary focus on quantifying its overall performance. The operating temperature is controlled by the flow of air on the backside of the PV panel inside the cold room. The level of radiation studied corresponds to a vertical integration of PV panels in building façades. The coefficient of the mean variation of the efficiency with the photovoltaic panels’ temperature was −0.52%/°C; for voltage, −0.48%/°C, and for current, +0.10%/°C.

Analysis and Performance Evaluation of Non-Toxic Organo-Metal Halide (CH3NH3SnI3) Perovskite Optical Absorber based Photovoltaic Cell

Tin-based Perovskite solar cells (PSC) have emerged as a promising alternative to environmentally hazardous lead-based Perovskite solar cells. The lead-free Perovskite compound (CH3NH3SnI3) is particularly appealing due to its wide absorption spectrum. Perovskite materials both organic and inorganic, exhibit exceptional optical features such as a high absorption coefficient, a tunable band gap, and manufacturing techniques based on solution. The optical absorber material has been used in a novel solar cell composition ITO/TiO2/CH3NH3SnI3/NiO/Mo. To assess the device's performance, several critical parameters were investigated, including, structural layer thickness, carrier mobility, and the defect density. The numerical investigations were carried through solar capacitance simulator SCAPS-1D. By using calculations, Perovskite (CH3NH3SnI3) optical absorbent layer's thickness for the optimum device efficiency was adjusted to 1.032μm, for electron transport layer (ETL) TiO2 the thicknesses was 0.002μm and hole transport layer (HTL) NiO (HTL) optimized thickness was adjusted to be 0.02μm. The device power conversion efficiency (PCE) was found to be 21.068%. Electrical parameters open circuit voltage (Voc), short circuit current (Jsc), Fill Factor (FF %) and quantum efficiency (QE) get influenced by variation in layers thicknesses and interface defect densities. The proposed composition has been thoroughly investigated, and the optimized device performance has been comprehensively analyzed in this study. Current investigations may help to design and manufacture the environmentally acceptable, non-toxic, and efficient solar cells.

High-performance full-etched fiber-to-chip grating couplers at 3.7-micron wavelength on silicon

Mid-infrared (MIR) silicon photonics have attracted great interest for potential applications in on-chip spectroscopy, free-space communication, and remote imaging. Currently, the high-performance and fabrication-friendly fiber-to-chip grating couplers operating at 3–4 μm wavelength band are still desired urgently. Here, we propose an efficient method for designing a 2D subwavelength grating coupler. The few analytical fitting parameters defining the subwavelength grating periods and fill factors in two dimensions enable a high design degree of freedom and a low search space dimension, resulting in high figure-of-merit and fast convergence simultaneously. The developed 3.7 μm grating coupler showcases record-high coupling efficiency both theoretically (−2.2 dB) and experimentally (−4.4 dB) among the 3–4 μm MIR counterparts. This study provides an effective method for designing fiber-to-chip grating couplers, by which the MIR grating couplers with high performance and fabrication ease are developed, thus paving the way for developing high-performance silicon photonic integrated circuits operating in the MIR wavelength band.

Analysis of work productivity and compatibility of excavation-loading equipment and transport equipment in soil salvaging activities at Katala Hill area of PT. Amman

Abstract PT. Amman Mineral Internasional Tbk in Katala Hill, West Nusa Tenggara Province, Indonesia, is an open-pit mining company producing copper as its main commodity, followed by gold and silver. The initial stage of mining involves soil removal in land clearing activities for reclamation, waste disposal areas, and construction of other infrastructure. In soil salvaging activities, it is essential to understand the influential factors to productivity and the match factor in mechanical equipment, including work efficiency, delay time, cycle time, fill factor, and swell factor. The objective of this study is to determine the productivity and match factor values of the digging-loading equipment and transportation equipment in soil salvaging activities in the Katala Hill area. This study applied the descriptive quantitative method, involving direct field observations of the digging-loading and transportation equipment activities and interviews with mining workers. Based on the results, the actual work efficiency of the digging-loading equipment was 59% and the transportation equipment was 76%, the actual productivity of the digging-loading equipment was 825.00Bcm/h, the transportation equipment productivity was 611.17 Bcm/h, and the compatibility factor value is 0.7408. After increasing the work efficiency of the conveyance by 83%, the conveyance productivity was 667.46 Bcm/h with the match factor increasing to 0.8090.

Dimeric Acceptors Using Different Central Linkers to Manipulate Electronic and Morphological Properties

AbstractDimerized acceptors show promise in combining the high performance of small‐molecule non‐fullerene acceptors (NFAs) with the excellent stability of polymer acceptors. The central linking units that connect two acceptor molecules together have a profound impact on dimeric acceptor properties and structure‐performance relationships in blended thin films. It is seen that different linkers significantly affect the electronic properties and morphology in blended thin film. The electron‐donating linker elevates the absorption coefficient, affords a lower bandgap, and reduces energy loss, and thus better photovoltaic device performance. Better fibrillar morphology can be obtained. The best material DY‐EDOT‐based device shows a power conversion efficiency (PCE) of 18.21%, an open‐circuit voltage (Voc) of 0.924 V, a short‐circuit current density (Jsc) of 25.20 mA cm−2, a fill factor (FF) of 78.19%, which is among the highest value for dimerized acceptors. This study reveals the fundamental importance of linker units in determining the dimerized acceptor properties and provides useful strategies for developing oligomeric and polymeric acceptors, which is critical in simultaneously improving the performance and stability of organic solar cells (OSCs).