Ionized Phenanthroline Derivatives Suppressing Interface Chemical Interactions with Active Layer for High-efficiency Organic Solar Cells with Exceptional Device Stability.

The contact interface between the charge transport interlayer and the active layer is crucial for the non-fullerene organic solar cells (NF OSCs) to achieve high efficiency and long-term stability. In this study, two novel phenanthroline (Phen) derivatives, tbp-Phen and tbp-PhenBr, are developed as efficient cathode interfacial materials (CIMs). The larger steric hindrance substituents and the ionization of nitrogen atoms on the Phen framework jointly enable the tbp-PhenBr CIM with a stable film morphology and immensely suppress the detrimental interface chemical interactions with the NF active layer.

Optimizing Active Layer Morphology of Organic Solar Cells by Constructing Random Copolymers with Simple Third Units.

The molecular structure of the polymer PM6 is elaborately modified through random copolymerization by incorporating simple units of either difluoro-substituted thiophene (2FT) or dicyano-substituted thiophene (2CNT). The incorporation of the 2FT unit significantly enhanced the coplanarity of the random copolymers, leading to improved molecular crystallinity, whereas the introduction of the 2CNT unit featured the opposite effect. Thanks to the optimized morphology resembling a fiber-like interpenetrating network structure, the organic solar cells based on PM6-10%2FT:IT4F showed higher and more balanced charge mobilities, achieving a power conversion efficiency (PCE) of 12.

Chemical Prelithiated 3D Lithiophilic/-Phobic Interlayer Enables Long-Term Li Plating/Stripping.

The up-to-date lifespan of zero-excess lithium (Li) metal batteries is limited to a few dozen cycles due to irreversible Li-ion loss caused by interfacial reactions during cycling. Herein, a chemical prelithiated composite interlayer, made of lithiophilic silver (Ag) and lithiophobic copper (Cu) in a 3D porous carbon fiber matrix, is applied on a planar Cu current collector to regulate Li plating and stripping and prevent undesired reactions. The Li-rich surface coating of lithium oxide (LiO), lithium carboxylate (RCOLi), lithium carbonates (ROCOLi), and lithium hydride (LiH) is formed by soaking and directly heating the interlayer in -butyllithium hexane solution.

Ethylenedioxythiophene-Based Small Molecular Donor with Multiple Conformation Locks for Organic Solar Cells with Efficiency of 19.3 .

Ternary organic solar cells (T-OSCs) represent an efficient strategy for enhancing the performance of OSCs. Presently, the majority of high-performance T-OSCs incorporates well-established Y-acceptors or donor polymers as the third component. In this study, a novel class of conjugated small molecules has been introduced as the third component, demonstrating exceptional photovoltaic performance in T-OSCs.

Electrocatalytic conversion of biomass-derived furan compounds: mechanisms, catalysts and perspectives.

Renewable biomass, with its abundant resources, provides a viable solution to address the energy crisis and mitigate environmental pollution. Furan compounds, including 5-hydroxymethylfurfural (HMF) and furfural (FF), serve as versatile platform molecules derived from the degradation of lignocellulosic cellulose, offering a crucial pathway for the conversion of renewable biomass. The electrocatalytic conversion of furan compounds using renewable electricity represents an enticing approach for transforming them into value-added chemicals.

Impact of Electrostatic Interaction on Vertical Morphology and Energy Loss in Efficient Pseudo-Planar Heterojunction Organic Solar Cells.

Although a suitable vertical phase separation (VPS) morphology is essential for improving charge transport efficiency, reducing charge recombination, and ultimately boosting the efficiency of organic solar cells (OSCs), there is a lack of theoretical guidance on how to achieve the ideal morphology. Herein, a relationship between the molecular structure and the VPS morphology of pseudo-planar heterojunction (PPHJ) OSCs is established by using molecular surface electrostatic potential (ESP) as a bridge. The morphological evolution mechanism is revealed by studying four binary systems with vary electrostatic potential difference (∆ESP) between donors (Ds) and acceptors (As).

Regulating Crystallinity Mismatch Between Donor and Acceptor to Improve Exciton/Charge Transport in Efficient Organic Solar Cells.

Achieving a more balanced charge transport by morphological control is crucial in reducing bimolecular and trap-assisted recombination and enhancing the critical parameters for efficient organic solar cells (OSCs). Hence, a facile strategy is proposed to reduce the crystallinity difference between donor and acceptor by incorporating a novel multifunctional liquid crystal small molecule (LCSM) BDTPF4-C6 into the binary blend. BDTPF4-C6 is the first LCSM based on a tetrafluorobenzene unit and features a low liquid crystal phase transition temperature and strong self-assembly ability, conducive to regulating the active layer morphology.

Green-Solvent Processed Blade-Coating Organic Solar Cells with an Efficiency Approaching 19% Enabled by Alkyl-Tailored Acceptors.

Power-conversion-efficiencies (PCEs) of organic solar cells (OSCs) in laboratory, normally processed by spin-coating technology with toxic halogenated solvents, have reached over 19%. However, there is usually a marked PCE drop when the blade-coating and/or green-solvents toward large-scale printing are used instead, which hampers the practical development of OSCs. Here, a new series of N-alkyl-tailored small molecule acceptors named YR-SeNF with a same molecular main backbone are developed by combining selenium-fused central-core and naphthalene-fused end-group.

Li-Ion Conductivity of Single-Step Synthesized Glassy-Ceramic LiGePS and Post-heated Highly Crystalline LiGePS.

LiGePS is a phosphosulfide solid electrolyte that exhibits exceptionally high Li-ion conductivity, reaching a conductivity above 10 S cm at room temperature, rivaling that of liquid electrolytes. Herein, a method to produce glassy-ceramic LiGePS via a single-step utilizing high-energy ball milling was developed and systematically studied. During the high energy milling process, the precursors experience three different stages, namely, the 'Vitrification zone' where the precursors undergo homogenization and amorphization, 'Intermediary zone' where LiPS and LiGeS are formed, and the 'Product stage' where the desired glassy-ceramic LiGePS is formed after 520 min of milling.

Impact of Electrostatic Interaction on Non-radiative Recombination Energy Losses in Organic Solar Cells Based on Asymmetric Acceptors.

Reducing non-radiative recombination energy loss (ΔE ) is one key to boosting the efficiency of organic solar cells. Although the recent studies have indicated that the Y-series asymmetric acceptors-based devices featured relatively low ΔE , the understanding of the energy loss mechanism derived from molecular structure change is still lagging behind. Herein, two asymmetric acceptors named BTP-Cl and BTP-2Cl with different terminals were synthesized to make a clear comparative study with the symmetric acceptor BTP-0Cl.

Disentangling the Li-Ion transport and Boundary Phase Transition Processes in Li GeP S Electrolyte by In-Operando High-Pressure and High-Resolution NMR Spectroscopy.

Li-ion transport and phase transition of solid electrolytes are critical and fundamental issues governing the rate and cycling performances of solid-state batteries. In this work, in-operando high-pressure nuclear magnetic resonance (NMR) spectroscopy for the solid-state battery is developed and applied, in combination with Li-tracer NMR and high-resolution NMR spectroscopy, to investigate the Li GeP S electrolyte under true-to-life operation conditions. The results reveal that the Li GeP S phase may become more disordered and a large amount of conductive metastable β-Li PS as the glassy matrix in the electrolyte transforms into less conductive phases, mainly γ-Li PS , when high current densities (e.

Terpolymerization and Regioisomerization Strategy to Construct Efficient Terpolymer Donors Enabling High-Performance Organic Solar Cells.

Terpolymerization and regioisomerization strategies are combined to develop novel polymer donors to overcome the difficulty of improving organic solar cells (OSCs) performance. Two novel isomeric units, bis(2-hexyldecyl)-2,5-bis(4-chlorothiophen-2-yl)thieno[3,2-b]thiophene-3,6-dicarboxylate (TTO) and bis(2-hexyldecyl) 2,5-bis(3-chlorothiophen-2-yl)thieno[3,2-b]thiophene-3,6-dicarboxylate (TTI), are obtained and incorporated into the PM6 backbone via random copolymerization to form a series of terpolymers. Interestingly, it is found that different chlorine (Cl) substituent positions can significantly change the molecular planarity and electrostatic potential (ESP) owing to the steric hindrance effect of the heavy Cl atom, which leads to different molecular aggregation behaviors and miscibility between the donor and acceptor.

Disentangling Phase and Morphological Evolution During the Formation of the Lithium Superionic Conductor Li GeP S.

The structural and morphological changes of the Lithium superionic conductor Li GeP S , prepared via a widely used ball milling-heating method over a comprehensive heat treatment range (50 - 700 °C), are investigated. Based on the phase composition, the formation process can be distinctly separated into four zones: Educt, Intermediary, Formation, and Decomposition zone. It is found that instead of Li GeS -Li PS binary crystallization process, diversified intermediate phases, including GeS in different space groups, multiphasic lithium phosphosulfides (Li P S ), and cubic Li Ge PS phase, are involved additionally during the formation and decomposition of Li GeP S .

Flexible Miniaturized Multispectral Detector Derived from Blade-Coated Organic Narrowband Response Unit Array.

Multispectral sensing is extremely desired in intelligent systems, e.g., autonomous vehicles, encrypted information communication, and health biometric monitoring, due to its highly sensitive spectral discrimination ability.

Achieving efficient and stabilized organic solar cells by precisely controlling the proportion of copolymerized units in electron-rich polymers.

A series of random polymers based on the donor polymer PM6 were designed from the perspective of regulating the surface electrostatic potential (ESP) distribution of the polymers and applied in organic solar cells (OSCs). Random polymers with different ESPs were obtained by introducing structural units of polymer PM6 into the polymer structure as the third unit. The simulation results showed that the random polymers feature a wider electron-donating region after the introduction of BDT units, indicating a more efficient charge generation probability.

Semicrystalline Conjugated Polymers with Well-Defined Active Sites for Nitrogen Fixation in a Seawater Electrolyte.

Faradaic efficiency for the nitrogen reduction reaction (NRR) is often limited by low N solubility in the electrolyte, while a large number of intimate contacts between the electrolyte and solid catalyst can also inevitably sacrifice many active sites for the NRR. Here, it is reported that a "quasi-gas-solid" interface formed in donor-acceptor-based conjugated polymers (CPs) is beneficial to boosting the NRR process and at the same time suppressing the competing hydrogen evolution reaction. Of particular interest, it is found that a semicrystalline CP catalyst, SC-PBDT-TT, exhibits a high Faradaic efficiency of up to 60.

Alkylsilyl Fused Ring-Based Polymer Donor for Non-Fullerene Solar Cells with Record Open Circuit Voltage and Energy Loss.

The energy loss (E ), especially the nonradiative recombination loss and energetic disorder, needs to be minimized to improve the device performance with a small voltage (V ) loss. Urbach energy (E ) of organic photovoltaic materials is related to energetic disorder, which can predict the E of the corresponding device. Herein, a polymer donor (PBDS-TCl) with Si and Cl functional atoms for organic solar cells (OSCs) is synthesized.

Thickness-Insensitive Anode Interface Layer for High-Efficiency Organic Solar Cells.

Thickness-insensitive anode interface layer materials are extremely crucial for commercial applications of organic solar cells (OSCs). Here, we have demonstrated a solution-processed and thickness-insensitive anode interfacial layer PCPDT-2Ph-H and employed it in large-area OSCs. The power conversion efficiency (PCE) of a PM6:Y6 device with a 0.

Printable Hole Transport Layer for 1.0 cm Organic Solar Cells.

Currently, most of the hole transport layers (HTLs) of organic solar cells (OSCs) are unable to meet the requirements of printing preparation, which imposes restrictions on the commercial process of the OSCs severely. Here, we report a printable HTL, PCPDTKH-TT. The PM6:Y6:PCBM device with PCPDTKH-TT as an HTL exhibits a power conversion efficiency (PCE) of 16.

Isomeric Effect of Wide Bandgap Polymer Donors with High Crystallinity to Achieve Efficient Polymer Solar Cells.

Two highly crystalline polymer donors (PBTz4T2C-a, PBTz4T2C-b) with isomers (4T2C-a, 4T2C-b) are synthesized and applied in polymer solar cells. The developed polymers possess proper energy levels and complementary absorption with an efficient electron acceptor IT2F. It is interesting that the photophysical properties, crystallinity, and active layer morphology characteristic can be significantly changed by just slightly regulating the substitution position of the carboxylate groups.

Bio-inspired vertebral design for scalable and flexible perovskite solar cells.

The translation of unparalleled efficiency from the lab-scale devices to practical-scale flexible modules affords a huge performance loss for flexible perovskite solar cells (PSCs). The degradation is attributed to the brittleness and discrepancy of perovskite crystal growth upon different substrates. Inspired by robust crystallization and flexible structure of vertebrae, herein, we employ a conductive and glued polymer between indium tin oxide and perovskite layers, which simultaneously facilitates oriented crystallization of perovskite and sticks the devices.

Fused selenophene-thieno[3,2-b]thiophene-selenophene (ST)-based narrow-bandgap electron acceptor for efficient organic solar cells with small voltage loss.

A novel near-infrared-light-absorbing fused-ring electron acceptor, STIC, was developed for organic solar cells. STIC exhibited a narrow bandgap with an absorption edge reaching 940 nm, which was ascribed to the strong electron-rich selenophene-thieno[3,2-b]thiophene-selenophene (ST) unit and strong intramolecular charge transfer of STIC. Also, STIC-based devices showed low open-circuit voltage (Voc) loss values, attributed to the rigid ST core providing low reorganization energy.

Dithienopicenocarbazole-Based Acceptors for Efficient Organic Solar Cells with Optoelectronic Response Over 1000 nm and an Extremely Low Energy Loss.

Two cheliform non-fullerene acceptors, DTPC-IC and DTPC-DFIC, based on a highly electron-rich core, dithienopicenocarbazole (DTPC), are synthesized, showing ultra-narrow bandgaps (as low as 1.21 eV). The two-dimensional nitrogen-containing conjugated DTPC possesses strong electron-donating capability, which induces intense intramolecular charge transfer and intermolecular π-π stacking in derived acceptors.

Synergistic effect of processing additives and thermal annealing in organic solar cells: the "Morphology of Magic".

Organic solar cells (OSCs) usually need to be optimized with the strategies of thermal annealing (TA), solvent vapor annealing (SVA), or processing additives (PA) to obtain the best performance. Here, PA and TA were used simultaneously for OSCs based on the novel organic molecules TBDT-T6ffBT and OBDT-T6ffBT. The synergistic effect of PA and TA on the active-layer morphologies was investigated by measurements of optical microscopy, atomic force microscopy, transmission electron microscopy, and grazing incident X-ray diffraction.