Initial Efficiency Research Articles

Decreased Hysteresis Benefited from Enhanced Lattice Oxygen and Promoted Band Alignment with Electron Transport Layer Modification in Perovskite Solar Cells.

SnO2 electron transport layer (ETL) morphology plays a vital role in carrier transportation and the properties of perovskite solar cells (PSCs). However, the uneven and pore surface would inevitably lead to high interface defects, high hysteresis, and poor performance. In this work, we use a molecular modifier 4-guanidinobenzoic acid methanesulfonate (GAMSA) to build a molecular bridge on the buried interface of SnO2/perovskite. XPS results demonstrate that the ratio of lattice oxygen (OL)/adsorbed oxygen (OV) increased from 1.35 to 2.34 after GAMSA modification, thus, Sn4+ and O vacancy defects in SnO2 were effectively reduced. Meanwhile, the conduction band minimum of the ETL enhanced from -4.33 eV to -4.07 eV, which obviously facilitated the electron transport. As a result, the optimal device exhibits an enhanced efficiency of 22.42%, which is much higher than that of the control one of 20.13%, with a greatly decreased hysteresis index from 14.35% to 3.27%. Notably, the optimized target device demonstrated excellent long-term stability, maintaining an initial efficiency of 87% after 2000 h storage in a N2 atmosphere in the dark at room temperature. This work paves a new method of ETL modification to improve lattice oxygen of SnO2 and restrain hysteresis for the enhanced performance of PSCs.

Innovating bio-lubricant design: utilizing Mordred descriptors for model development and thermal stability prediction of novel compounds

Purpose Developing bio-lubricants for high-temperature applications, such as engine operations, requires reliable thermal stability assessment. This study aims to create a predictive tool to evaluate thermal stability using existing organic compounds data. The model predicts the onset temperature (T onset) of bio-lubricant candidates derived from epoxidation with various amine nucleophiles, enhancing initial selection efficiency and reducing reliance on traditional trial-and-error methods. Design/methodology/approach Using the Python library Mordred, molecular descriptors were calculated from the SMILES structures of 126 compounds with known T onsets. These descriptors were inputs for machine learning models predicting the thermal stability of bio-lubricants. The models were evaluated on training and test data sets and validated with novel synthesized compounds. Findings The predictive model showed strong performance on the test data set, with an R² of 0.93 and a root mean square error of 17.77. In external validation, the model estimated the thermal stability of a novel bio-lubricant compound (MA-EPO) at 290.7°C, closely matching the actual T onset of approximately 300°C. Originality/value This research introduces a method for predicting the thermal stability of bio-lubricants using machine learning and open-source libraries. This approach significantly advances the field by improving the efficiency of bio-lubricant development for high-temperature applications. It provides a cost-effective and time-saving alternative to traditional experimental methods, serving as a valuable resource for researchers and developers in the bio-lubricant industry.

Role of Water in the Stability and Efficiency of Ionic Liquid-Based Perovskite Solar Cells.

The fabrication of perovskite solar cells (PSCs) in ambient air can accelerate their industrialization. However, moisture causes severe decomposition of the perovskite materials, limiting device efficiency. Here, we demonstrate that, compared to traditional N,N-dimethylformamide-based precursor solutions, the ionic liquid methylammonium acetate (MAAc) system forms a protective layer on the perovskite surface due to the C═O···Pb and N-H···I interactions between MAAc and PbI64-, which effectively prevents direct contact between the perovskite components and water. Moreover, we show that a certain level of humidity weakens the interactions between MAAc and PbI64-, promoting the crystallization process and resulting in films with fewer defects. PSCs based on MAAc achieved a power conversion efficiency of 20.73% under optimal water content conditions, and the unencapsulated devices maintained >83% of their initial efficiency after >1300 h in ambient air.

Manipulating Interphase Chemistry for Aqueous Zn Stabilization: The Role of Supersaturation

AbstractThe limited cycling durability of Zn anode, attributed to the absence of a robust electrolyte‐derived solid electrolyte interphase (SEI), remains the bottleneck for the practical deployment of aqueous zinc batteries. Herein, we highlight the role of local supersaturation in governing the fundamental crystallization chemistry of Zn4SO4(OH)6⋅xH2O (ZSH) and propose a subtle supersaturation‐controlled morphology strategy to tailor the interphase chemistry of Zn anode. By judiciously creating local high‐supersaturation environment with organic caprolactam to manipulate the precipitation manner of zinc sulfate hydroxide (ZSH), lattice‐lattice matched heterogeneous nucleation of ZSH (001) and Zn (002) is realized in aqueous ZnSO4, producing a dense, pseudo‐coincidence interface capable of functioning as decent SEI. The plating/stripping efficacy of Zn is significantly boosted, as reflected by the great improvement of the initial (from 59.9 % to 84.1 %) and average (from 94.0 % to 99.2 %) coulombic efficiency. Accordingly, the cyclic endurance of Zn anode is prolonged from 50 h to over 7000 h at 0.5 mA cm−2/1 mAh cm−2, witnessing 140‐fold lifespan extension. Profiting from supersaturation‐mediated Zn stabilization, the performance deterioration of zinc‐vanadium batteries is also alleviated, even with a low N/P ratio of 4.4. This work is anticipated to deepen current understanding on the control of the anodic chemistry.

Lithium Carbide Prelithiation Agent‐Coated Separator Facilitates Compact Expansion of Silicon Electrode

AbstractThe high specific capacity and safety nature of silicon (Si) anode has garnered significant attention and investment for its application in high‐energy‐density lithium‐ion batteries (LIBs). However, the Si anode exhibits low initial Coulombic Efficiency (CE) and compromised cycle stability due to interfacial side reactions and the volume expansion of Si particles. Here, a straightforward strategy is proposed to prelithiate Si anodes and enhance the cycle stability by utilizing a lithium carbide (LiC6) coated separator. By incorporating a LiC6 prelithiation agent‐coated PP/PE separator (PP/PE@LiC6), a robust interaction between PP/PE@LiC6 and Si anode forms during cycling, which significantly reduces subsequent contact between the electrolyte and Si particles, thereby minimizing excessive electrolyte decomposition during cycling, and facilitates the compact expansion of the Si electrode. In Si|PP/PE@LiC6|Li cell, the initial CE reaches 108.51%, showcasing enhanced electrochemical stability (77.93% after 100 cycles). Moreover, the Si|PP/PE@LiC6|LiFePO4 cell also exhibits exceptional initial CE of ≈93.02% and improved electrochemical stability (100.94% after 100 cycles at 0.33C). This study introduces a secure and readily attainable prelithiation method for industrial applications of high‐energy density Si‐based batteries.

Manipulating Interphase Chemistry for Aqueous Zn Stabilization: The Role of Supersaturation.

The limited cycling durability of Zn anode, attributed to the absence of a robust electrolyte-derived solid electrolyte interphase (SEI), remains the bottleneck for the practical deployment of aqueous zinc batteries. Herein, we highlight the role of local supersaturation in governing the fundamental crystallization chemistry of Zn4SO4(OH)6⋅xH2O (ZSH) and propose a subtle supersaturation-controlled morphology strategy to tailor the interphase chemistry of Zn anode. By judiciously creating local high-supersaturation environment with organic caprolactam to manipulate the precipitation manner of zinc sulfate hydroxide (ZSH), lattice-lattice matched heterogeneous nucleation of ZSH (001) and Zn (002) is realized in aqueous ZnSO4, producing a dense, pseudo-coincidence interface capable of functioning as decent SEI. The plating/stripping efficacy of Zn is significantly boosted, as reflected by the great improvement of the initial (from 59.9 % to 84.1 %) and average (from 94.0 % to 99.2 %) coulombic efficiency. Accordingly, the cyclic endurance of Zn anode is prolonged from 50 h to over 7000 h at 0.5 mA cm-2/1 mAh cm-2, witnessing 140-fold lifespan extension. Profiting from supersaturation-mediated Zn stabilization, the performance deterioration of zinc-vanadium batteries is also alleviated, even with a low N/P ratio of 4.4. This work is anticipated to deepen current understanding on the control of the anodic chemistry.

Multi-Component Phase Engineering Strategy Modulates Potassiation Reaction Energy Barrier of Alloying Anode for Stable Potassium Storage.

Red phosphorus (RP) has received much attention in potassium storage because of its inexpensive cost and high theoretical capacity, but faces the issues of volume expansion and poor conductivity. Fortunately, phosphorus-selenium hybridization solves these issues by forming an alloy anode that combines RP's high capacity with Se's high conductivity. But the weak chemical affinity between RP and Se makes it often difficult to form stable and homogeneous mixtures during preparation. To address this, this study introduces hexagonal boron nitride (h-BN) as a bridging source to facilitate the close coupling of the RP and Se composite phases. The optimized multi-component anode exhibits high initial coulombic efficiency (ICE reaching 73.0%), good cycling stability (3000 cycles at 1 A g-1), and outstanding rate performance (a discharge specific capacity of 157.3 mAh g⁻¹ even at 2 A g⁻¹). Further investigation reveals that the introduction of h-BN reduces activation energy for interfacial charge transfer and K+ to cross the solid electrolyte interphase (SEI). It also decreases the Gibbs free energy change (ΔG) of the potassiation reaction's decisive step. Therefore, the introduction of a third phase enhances the coupling effect of alloy-based composites, providing a method for designing secondary battery electrodes with high capacity.

Colloidal Ink Engineering for Slot-Die Processes to Realize Highly Efficient and Robust Perovskite Solar Modules.

Perovskite solar cells (PSCs) have emerged as a promising alternative to silicon solar cells, but challenges remain in developing perovskite inks and processes suitable for large-scale production. This study introduces a novel approach using colloidal inks incorporating toluene and chlorobenzene as co-antisolvents for PSC fabrication via slot-die process. It is found that colloidal inks that are strategically engineered can significantly improve the rheological properties of perovskite inks, leading to enhanced wettability and high-quality film formation. The formation of large colloids such as α cubic perovskite, δ hexagonal perovskite and transition intermediate phases promotes heterogeneous nucleation and lowers activation energy for crystallization, resulting in superior crystal growth and improved film morphology. Notably, the co-solvent enhances the FA-PbI3 binding energy and weakens the dimethyl sulfoxide coordination, which is more thermodynamically favorable for perovskite crystallization. This colloidal strategy yields devices with a maximum efficiency of 21.32% and remarkable long-term stability, retaining 77% of initial efficiency over 10115 h. The study demonstrates the scalability of this approach, achieving 20.26% efficiency in lab-scale minimodules and 19.15% in larger convergence minimodules. These findings provide an understanding of the complex relationship between ink composition, rheological properties, film quality, crystallization kinetics, and device performance.

Synthesis of novel magnesium ferrite Schiff base chitosan nanocomposite for efficient removal of pb(II) ions from aqueous media

In this study, a novel MgFe2O4-Schiff base-chitosan nanocomposite was synthesized using a straightforward crosslinking method. The synthesis involved integrating MgFe2O4 nanoparticles with modified chitosan through a Schiff base formed by the reaction between terephthalaldehyde and aminopyrazine. A comprehensive characterization was performed, including X-ray diffraction analysis, which verified the crystalline structure and the successful incorporation of MgFe2O nanoparticles into the chitosan-Schiff base matrix. Scanning electron microscopy revealed a distinct surface morphology, characterized by a rough, non-uniform alignment resulting from the strong interactions between the nanoparticles and the Schiff base-chitosan matrix. Additionally, energy-dispersive X-ray analysis verified the elemental composition of the nanocomposite, revealing distinct peaks corresponding to carbon, nitrogen, oxygen, magnesium, and iron. The nanocomposite exhibited outstanding performance as a nanoadsorbent for the efficient removal of Pb(II) ions from aqueous media through electrostatic attraction and complexation mechanisms, achieving a maximum adsorption capacity of 290.7 mg g-1. The adsorption process was determined to be spontaneous, endothermic, and chemically driven, aligning well with the Langmuir isotherm model and pseudo-second-order kinetics. The optimal conditions for maximum Pb(II) ions removal were determined to be a pH of 5.5, a contact time of 100 min, and a temperature of 328 K. Furthermore, the nanocomposite demonstrated excellent recyclability, retaining over 94.8% of its initial removal efficiency after five consecutive adsorption-desorption cycles. This study highlights the nanocomposite’s potential as an eco-friendly, cost-effective, and highly efficient material for practical applications in water treatment, addressing the urgent need for sustainable solutions to heavy metal contamination.

Tailoring Buried Interface and Minimizing Energy Loss Enable Efficient Narrow and Wide Bandgap Inverted Perovskite Solar Cells by Aluminum Glycinate Based Organometallic Molecule.

Rational regulation of Me-4PACz/perovskite interface has emerged as a significant challenge in the pursuit of highly efficient and stable perovskite solar cells (PSCs). Herein, an organometallic molecule of aluminum glycinate (AG) that contained amine (-NH2) and aluminum hydroxyl (Al-OH) groups is developed to tailor the buried interface and minimize interface-driven energy losses. The Al-OH groups selectively bonded with unanchored O═P-OH and bare NiO-OH to optimize the surface morphology and energy levels, while the -NH2 group interacted specifically with Pb2+ to retard perovskite crystallization, passivate buried Pb-related defects, and release residual interface stress. These interactions facilitate the interface carrier extraction and reduce interface-driven energy losses, thereby realizing a balanced charge carrier transport. Consequently, AG-modified narrow bandgap (1.55 eV) PSC demonstrates an efficiency of 26.74% (certified 26.21%) with a fill factor of 86.65%; AG-modified wide bandgap (1.785 eV) PSC realizes 20.71% champion efficiency with excellent repeatability. These PSCs maintain 91.37%, 91.92%, and 92.00% of their initial efficiency after aging in air atmosphere, the nitrogen-filled atmosphere at 85°C, and continuously tracking at the maximum power-point under one-sun illumination (100 mW cm-2) for 1200 h, respectively.

CsSnI3 Quantum Dots as a Multifunctional Interlayer for High‐Efficiency Bilayer Perovskite Solar Cells

AbstractPerovskite solar cells (PSCs) have garnered significant interest due to their potential for high performance at low cost. While single‐junction PSCs have surpassed 26% efficiency, they are nearing their theoretical limits. Introducing dual absorber layers can broaden the spectral absorption range, enhancing performance. This study explores a zero‐dimensional/three‐dimensional (0D/3D) bilayer structure combining three‐dimensional (3D) FAPbI3 with zero‐dimensional (0D) cesium tin triiodide (CsSnI3) quantum dots (QDs) as an interfacial modification layer. The CsSnI3 QDs establish a cascade energy level structure, improving charge transfer efficiency at the perovskite‐hole transport layer (HTL) interface. Their narrow bandgap enhances light absorption efficiency, boosting hole extraction and short‐circuit current density. Incorporating CsSnI3 QDs into PSCs significantly improves the power conversion efficiency from 22.99% to 25.72% compared to 3D perovskite solar cells without the CsSnI3 QD interlayer. Also, surface‐passivated CsSnI3 QDs with hydrophobic ligands provide moisture resistance and interfacial passivation, increasing stability. Using perfluorooctanoic acid (PFA) to modify CsSnI3 QDs further enhances moisture resistance, allowing PSCs to maintain 85% of initial efficiency for over 60 days at 25% relative humidity without encapsulation, demonstrating significant stability improvements. The incorporation of CsSnI3 QDs in PSCs notably increases power conversion efficiency.

Molecular Bridge in Wide‐Bandgap Perovskites for Efficient and Stable Perovskite/ Silicon Tandem Solar Cells

AbstractPerovskite/silicon tandem solar cells (TSCs) attract intensive attention because of their potential to deliver power conversion efficiencies (PCE) beyond those of their single‐junction counterparts. However, the performance and stability of tandem devices are limited by defect‐assisted non‐radiative recombination and light‐induced halide segregation in wide‐bandgap (WBG) perovskite sub‐cells. Here, 2‐aminoethanesulfonamide hydrochloride (AESCl), with multi‐point chelation sites and bridging capability, is incorporated into a 1.68 eV WBG perovskite to comprehensively passivate defects at grain boundaries and surfaces. As a result, AESCl‐treated perovskite films show suppressed halide segregation and a champion WBG single‐junction solar cell achieves an impressive efficiency of 22.80% with an open‐circuit voltage of 1.286 V due to reduced non‐radiative recombination. The efficient WBG perovskite sub‐cells enable perovskite/silicon TSCs to reach a champion PCE of 30.36% over 1 cm2. Moreover, the tandem devices retain over 96% of their initial efficiency after operation for 1068 h under continuous AM 1.5G illumination at 25 °C in ambient air.

Graphitized Layers Encapsulated Carbon Nanofibers as Li-Free Anode for Hybrid Li-Ion/Metal Batteries.

Hard carbon, the Li-free anode for hybrid Li-ion/metal batteries (LIB/LMBs), has great potential for enhancing fast charging capability, energy density, and battery lifespan. However, low initial Coulombic efficiency (ICE) and Li dendrite growth are crucial factors constraining its development. In this work, graphitized layers encapsulated carbon nanofibers (G-CF) are fabricated via Joule heating within 10 s. The Csp2 structure in graphitized layers reduces side reactions with the electrolyte, promotes LiC compound formation, and improves Li ions/metal reversibility. The inner amorphous carbon structure boosts fast charging capability. As a result, the G-CF anode attains an 85.2% high ICE and exhibits long-term cycling stability. Under 2 C fast charging, it maintains an average Coulombic efficiency of 99.94% and a 500 mAh g-1 capacity after 200 cycles. Moreover, when the N/P ratio is 0.5, the G-CF||NCM811full cell has an ICE of 84.5% and provides a capacity of 530.8 mAh g-1 and an energy density of 365.9Wh kg-1 at 1C. The G-CF||LFP full cell can also provide a capacity of 541.0 mAh g-1 under the same N/P ratio. A 30 mAh pouch cell can stably cycle over 100 times. This heterogeneous hard carbon design paves a revolutionary path for manufacturing high-efficiency Li-free anodes for hybrid LIB/LMBs.

Simple Synthesis and Sodium Storage Analysis of Ultra‐High Nitrogen‐Doped Core‐Shell Mesoporous Carbon Nanospheres

AbstractThe development of easily synthesized high‐performance anode materials is crucial for the current energy storage (ES) field. Considering the potential of nitrogen‐doped core‐shell mesoporous carbon materials, a simple micelle‐induced high‐temperature pyrolysis method is employed to synthesize ultra‐high nitrogen‐doped (21.1 wt.%) core‐shell mesoporous carbon nanospheres (CYMCS). This material exhibits excellent volume expansion resistance, achieves a high reversible sodium storage capacity of up to 283 mAh g−1 at a current density of 0.1 A g−1, and maintains stable cycling performance for over 10000 cycles at a high current density of 5 A g−1. Moreover, previous research has provided limited insights into the specific mechanisms behind the low initial coulombic efficiency (ICE) observed in CYMCS and other related porous materials. To address this, the study not only delves into the electrochemical performance of CYMCS but also provides a comprehensive analysis of the formation mechanisms of the solid electrolyte interphase (SEI) and the electrolyte decomposition process, revealing the connections between these processes and their impact on ICE. Overall, this research not only offers new insights into the synthesis and performance optimization of CYMCS materials for sodium storage applications but also provides valuable guidance for the design of related carbon materials and strategies to improve ICE.

Production and Bioseparation Applications of Polyhydroxyalkanoate Nano-Granules Functionalized with Streptavidin

Rapidly growing industrial biotechnology and bio-manufacturing require simple and cost-effective bioseparation tools. A novel strategy of bioseparation based on the streptavidin-decorated polyhydroxyalkanoate (PHA) nano-granules was developed in this study. By fusing to the N-terminus of PHA-associated phasin protein, the streptavidin was one-step immobilized on the surface of PHA nano-granules simultaneously with the accumulation of PHA in recombinant Escherichia coli. About 1.95 g/L of PHA nano-granules (54.51 wt% of cell dry weight) were produced after 48 h bacterial cultivation. The following qualitative and quantitative characterizations demonstrated that the streptavidin accounted for approximately 6.78% of the total weight of the purified PHA nano-granules and confirmed a considerable biotin affinity of 0.1 ng biotin/μg surface protein. As a proof of concept, the nano-granules were further functionalized with biotinylated oligo(dT) for mRNA isolation and about 1.26 μg of mRNA (occupied 2.59%) was purified from 48.45 μg of total RNA, achieving good integrity and high purity with few DNA and rRNA contaminations. Moreover, the nano-granules retained more than 80% of their initial mRNA recovery efficiency after ten cycles of repeated use. The PHA-SAP nano-granules were also functionalized with biotinylated magnetic beads, allowing magnetic recovery of the PHA nano-granules from cell lysates that still needs optimization. Our study provides a novel and expandable platform of PHA nano-granules that can be further functionalized with various biological groups for bioseparation applications. The functional PHA nano-granules have a great potential to serve as bioseparation resin for large-scale purification processes after suitable optimizations for “bench-to-factory” translation, contributing to scalable and sustainable bioprocessing.

Removal of fluoride from wastewater with the Mg/Al impregnated adsorbent prepared from Chinar leaves: Adsorption isotherm, kinetic and thermodynamic studies.

The present study focuses on creating a novel functionalized adsorbent AC-Al-Mg-La for the extraction of fluoride ions from wastewater. The characterizations of the adsorbent were analyzed before and after modification by employing the techniques such as FTIR, XRD, SEMand zeta potential. The suggested adsorbent materials were evaluated for their effectiveness in treating fluoridated water. The impacts of the adsorbent dosage, initial pollutant level, water pH, and regeneration efficiency were assessed. Fluoride ion adsorption was highest at the optimal conditions of pH 4.0 ± 0.1; 30 minutes contact time, and a 0.15 g/L adsorbent dose. However, adsorption efficiency decreased at higher pH levels.At pH 4.0 ± 0.1, the peak adsorption efficiencies observed after 30 minutes of contact time with 0.15 g/L of the adsorbent dose were 72% for AC-La, 81% for AC-Al, 89% for AC-Mg, and 96% for AC-Al-Mg-La. The analysis of the AC-Al-Mg-La material's regeneration capabilities showed that, even after five consecutive cycles of adsorption and regeneration, it maintained decontamination potential of 71% after first cycle and reduced to 41% after fifth regeneration, representing a 30% reduction in effectiveness. This paper intends to encourage novel ideas and advancements in the creation of the next generation of eco-friendly adsorbent for defluorination.

All biomass-derived autogenous nitrogen-doped porous carbon with pseudo-graphitic structure for advanced lithium-ion battery anodes

All biomass-derived autogenous nitrogen-doped porous carbon with pseudo-graphitic structure for advanced lithium-ion battery anodes

Enhancing micro-scale SiOx anode durability: Electro-mechanical strengthening of binder networks via anchoring carbon nanotubes with carboxymethyl cellulose

Enhancing micro-scale SiOx anode durability: Electro-mechanical strengthening of binder networks via anchoring carbon nanotubes with carboxymethyl cellulose

One-step fabrication of binder-free nanoSi-CNT-carbon black/cyclized PAN composite anode for high-performance lithium-ion batteries

One-step fabrication of binder-free nanoSi-CNT-carbon black/cyclized PAN composite anode for high-performance lithium-ion batteries

Pt-Doped Co3O4 Nanowires as High-Efficiency Cathodic Catalysts for Improved Lithium-Oxygen Batteries and Insights into The Electrochemical Reaction Pathway

Pt-Doped Co3O4 Nanowires as High-Efficiency Cathodic Catalysts for Improved Lithium-Oxygen Batteries and Insights into The Electrochemical Reaction Pathway