New Polymeric Acceptors Based on Benzo[1,2-b:4,5-b'] Difuran Moiety for Efficient All-Polymer Solar Cells.

In order to realize high-performance bulk-heterojunction (BHJ) all-polymer solar cells, achieving appropriate aggregation and moderate miscibility of the polymer blends is one critical factor. Herein, this study designs and synthesizes two new polymer acceptors (Ps), namely PYF and PYF-Cl, containing benzo[1,2-b:4,5-b'] difuran (BDF) moiety with/without chlorine atoms on the thiophene side groups. Thanks to the preferred planar structure and high electronegativity of the BDF units, the resultant Ps generate strong intermolecular interactions and π-π stacking in both the neat and blend films.

Rational Design Dithieno[3,2-f:2',3'-h]quinoxaline-Based Polymers with Optimized Molecular Configuration and Charge Transfer for High-Performance All-Polymer Solar Cells.

Due to poor planarity and weak intermolecular interactions of acceptor units which have two-dimensional configuration, the development of related polymers is slow. In this work, we synthesized a dithieno[3,2-f:2',3'-h]quinoxaline-based unit substituted with fluorinated thiophene, which can effectively expand the area of the acceptor unit. Then, it paired with three different benzodithiophene-based donor units, and three new polymers of PQTF-BT, PQTF-BTCl and PQTF-DTCl were obtained.

Non-Fused π-Extension of Endcaps of Small Molecular Acceptors Enabling High-Performance Organic Solar Cells.

The modular structure of small molecular acceptors (SMAs) allows for versatile modifications of the materials and boosts the photovoltaic efficiencies of organic solar cells (OSCs) in recent years. As a critical component, the endcaps of SMAs have been intensively investigated and modified to control the molecular aggregation and photo-electronic conversion. However, most of the studies focus on halogenation or π-fusion extension of the endcap moieties, but overlook the non-fused π-extension approach, which could be a promising strategy to balance the self-aggregation and compatibility behaviors.

Efficient and Stable All-Polymer Solar Cells Enabled by Dual Working Mechanism.

Ternary strategy with integration characteristics and adaptability is a simple and effective method for blooming of the performance of photovoltaic devices. Herein, a novel wideband gap polymer donor PBB2-Hs is synthesized as the guest component to optimize all-polymer solar cells (all-PSCs). High-energy photon absorption and long exciton lifetime of PBB2-Hs constitute efficient energy transfer.

Efficient Dual Mechanisms Boost the Efficiency of Ternary Solar Cells with Two Compatible Polymer Donors to Exceed 19.

Ternary strategyopens a simple avenue to improve the power conversion efficiency (PCE) of organic solar cells (OSCs). The introduction of wide bandgap polymer donors (PDs) as third component canbetter utilize sunlight and improve the mechanical and thermal stability of active layer. However, efficient ternary OSCs (TOSCs) with two PDs are rarely reported due to inferior compatibility and shortage of efficient PDs match with acceptors.

Structure-Activity Relationship between Crystallinity and Carrier Transport of Two-Dimensional Donor Units in Organic Solar Cells.

Benzo[1,2-b:4,5-b']dithiophene (BDT) and its derivatives have made important contributions to constructing high-performance polymers. However, it is difficult to clarify the real role of donor units due to the interference of strong electronegativity and crystallinity of acceptor units in the D-A copolymer. Here, we design a cyclohexane-substituted dithieno[3,2-f:2',3'-h]quinoxaline (DTQ)-based acceptor unit with successfully destroyed crystallinity and charge transport.

Embedded Host/Guest Alloy Aggregations Enable High-Performance Ternary Organic Photovoltaics.

The ternary strategy has been intensively studied to improve the power conversion efficiencies of organic photovoltaics. Thereinto, the location of the guest component plays a critical role, but few reports have been devoted to this concern. Hereon, the distribution of LA1 as a guest acceptor in a variety of ternary scenarios is reported and the dominating driving forces of managing the guest distribution and operating modes are outlined.

Formation of Efficient Quasi-All-Polymer Solar Cells by Synergistic Effect of the Ternary Strategy and Solid Additives.

All-polymer solar cells (all-PSCs) have been widely studied owing to their unique mechanical flexibility and stability. However, all-PSCs have a lower efficiency than small-molecule acceptor-based PSCs. In the work, a ternary quasi-all-polymer solar cell (Q-all-PSC) using a synergy of the ternary strategy and solid additive engineering is reported.

Enhancing thermal conductivity and chemical protection of bacterial cellulose/silver nanowires thin-film for high flexible electronic skin.

Silver nanowires (AgNWs) thin films have emerged as a promising next-generation flexible electronic device. However, the current AgNWs thin films are often plagued by high AgNWs-AgNWs contact resistance and poor long-term stability. Here, to enhance the AgNWs stability on the surface of bacterial cellulose (BC), a novel flexible high conductivity thin-film was prepared by spin-coating a layer of polyvinyl alcohol (PVA) on the BC/AgNWs (BA) film.

Over 19% Efficiency Organic Solar Cells by Regulating Multidimensional Intermolecular Interactions.

Research on organic solar cells (OSCs) has progressed through material innovation and device engineering. However, well-known and ubiquitous intermolecular interactions, and particularly their synergistic effects, have received little attention. Herein, the complicated relationship between photovoltaic conversion and multidimensional intermolecular interactions in the active layers is investigated.

End Group Effect of Asymmetric Benzodithiophene-Based Donor with Liquid-Crystal State for Small-Molecule Binary Solar Cell.

Liquid-crystal small molecule donor (LC-SMD) is a new type organic semiconductor, which is attractive not only for the easy synthesis and purification, well-defined chemical structures, etc., but also for the LC state that makes the crystallinity and aggregation state of molecules adjustable. Here, one new LC-SMD (a-BTR-H4) is synthesized with 1D alkoxyl and 2D thiophene-alkylthiol side-chained benzo[1,2-b:4,5-b']dithiophene core, trithiophene π-bridge, and 3-(2-ethylhexyl) rhodanine end group.

Biomimetic FeCo@PDA nanozyme platform with Fenton catalytic activity as efficient antibacterial agent.

The multidrug resistance of bacteria caused by the abuse of traditional antibiotics poses a great threat to public health, so it is urgent to develop effective antibacterial agents to deal with this dilemma. Biomimetics and nanotechnology are expected to provide new strategies for solving this problem. This study takes inspiration from the adhesive protein properties of mussels to design and synthesise biomimetic polydopamine nanospheres (FeCo@PDA NPs), which have strong adhesion and catalytic Fenton reactive enzyme activity.

Photoinduced large polaron transport and dynamics in organic-inorganic hybrid lead halide perovskite with terahertz probes.

Organic-inorganic hybrid metal halide perovskites (MHPs) have attracted tremendous attention for optoelectronic applications. The long photocarrier lifetime and moderate carrier mobility have been proposed as results of the large polaron formation in MHPs. However, it is challenging to measure the effective mass and carrier scattering parameters of the photogenerated large polarons in the ultrafast carrier recombination dynamics.

Impact of backbone linkage positions on the molecular aggregation behavior of polymer photovoltaic materials.

It is imperative to advance the structural design of conjugated materials to achieve a practical impact on the performance of photovoltaic devices. However, the effect of the linkage positions (-, -) of the backbone on the molecular packing has been relatively little explored. In this study, we have synthesized two wide-bandgap polymer photovoltaic materials from identical monomers with different linkage positions, using dibenzo[,][2,6]-naphthyridine-5,11-(6,12)-dione (DBND) as the building block.

Two Compatible Acceptors as an Alloy Model with a Halogen-Free Solvent for Efficient Ternary Polymer Solar Cells.

A ternary strategy of halogen-free solvent processing can open up a promising pathway for the preparation of polymer solar cells (PSCs) on a large scale and can effectively improve the power conversion efficiency with an appropriate third component. Herein, the green solvent -xylene (-XY) is used as the main solvent, and the non-fullerene acceptor Y6-DT-4F as the third component is introduced into the PBB-F:IT-4F binary system to broaden the spectral absorption and optimize the morphology to achieve efficient PSCs. The third component, Y6-DT-4F, is compatible with IT-4F and can form an "alloy acceptor", which can synergistically optimize the photon capture, carrier transport, and collection capabilities of the ternary device.

Subtle Side Chain Triggers Unexpected Two-Channel Charge Transport Property Enabling 80% Fill Factors and Efficient Thick-Film Organic Photovoltaics.

To clearly show how important the impact of side chains on organic solar cells (OSCs) is, we designed three acceptors IDIC-CPh ( = 4, 5, or 6) via subtle side-chain regulation. Despite this small change, significant distinctions were detected. IDIC-C4Ph devices achieve an optimal efficiency of 13.

Benzo(Thiazole)-Based Conjugated Polymer with Varying Alkylthio Side-Chain Positions for Efficient Fullerene-Free Organic Solar Cells.

Alkylthio groups can be used to modulate energy levels and molecular packing of organic semiconductors, which makes it important in the design of materials for organic solar cell. However, its effect has not been sufficiently exploited as most of the studies report introducing an alkylthio group to the donor unit and seldom to the acceptor unit of donor-acceptor conjugated polymers. In this report, two alkylthio-substituted polymers, namely, PBB-TSA and PBB-TSD, with benzo[1,2-:4,5-'](thiazole) (BBT) as the acceptor unit and benzo[1,2-:4,5-']dithiophene (BDT) as the donor unit, were rationally designed, synthesized, and applied in organic photovoltaics.

Significantly Boosting Efficiency of Polymer Solar Cells by Employing a Nontoxic Halogen-Free Additive.

Traditional additives like 1,8-diiodooctane and 1-chloronaphthalene were successfully utilized morphology optimization of various polymer solar cells (PSCs) in an active layer, but their toxicity brought by halogen atoms limits their corresponding large-scale manufacturing. Herein, a new nontoxic halogen-free additive named benzyl benzoate (BB) was introduced into the classic PSCs (PTB7-Th:PCBM), and an optimal power conversion efficiency (PCE) of 9.43% was realized, while there was a poor PCE for additive free devices (4.

Suppressing the Photocatalytic Activity of Zinc Oxide Electron-Transport Layer in Nonfullerene Organic Solar Cells with a Pyrene-Bodipy Interlayer.

Organic solar cells based on nonfullerene acceptors have recently witnessed a significant rise in their power conversion efficiency values. However, they still suffer from severe instability issues, especially in an inverted device architecture based on the zinc oxide bottom electron transport layers. In this work, we insert a pyrene-bodipy donor-acceptor dye as a thin interlayer at the photoactive layer/zinc oxide interface to suppress the degradation reaction of the nonfullerene acceptor caused by the photocatalytic activity of zinc oxide.

Optimized Molecular Packing and Nonradiative Energy Loss Based on Terpolymer Methodology Combining Two Asymmetric Segments for High-Performance Polymer Solar Cells.

In this work, a random terpolymer methodology combining two electron-rich units, asymmetric thienobenzodithiophene (TBD) and thieno[2,3-]benzofuran segments, is systematically investigated. The synergetic effect is embodied on the molecular packing and nanophase when copolymerized with 1,3-bis(2-ethylhexyl)benzo[1,2-:4,5-']dithiophene-4,8-dione, producing an impressive power conversion efficiency (PCE) of 14.2% in IT-4F-based NF-PSCs, which outperformed the corresponding D-A copolymers.

Insights into Excitonic Dynamics of Terpolymer-Based High-Efficiency Nonfullerene Polymer Solar Cells: Enhancing the Yield of Charge Separation States.

Ternary copolymerization strategy is considered an effective method to achieve high-performance photovoltaic conjugated polymers. Herein, a donor-acceptor1-donor-acceptor2-type random copolymer, named PBDTNS-TZ-BDD (T1), containing one electron-rich unit alkylthionaphthyl-flanked benzo[1,2-/4,5-'] di-thiophene (BDTNS) as D and two electron-deficient moieties benzo[1,2-/4,5-']dithiophene-4,8-dione (BDD) and fluorinated benzotriazole as A, was synthesized to investigate the excitonic dynamic effect. Also, the D-A-type alternating copolymer PBDTNS-BDD (P1) was also prepared for a clear comparison.

Enhanced Organic and Perovskite Solar Cell Performance through Modification of the Electron-Selective Contact with a Bodipy-Porphyrin Dyad.

Photovoltaic devices based on organic semiconductors and organo-metal halide perovskites have not yet reached the theoretically predicted power conversion efficiencies while they still exhibit poor environmental stability. Interfacial engineering using suitable materials has been recognized as an attractive approach to tackle the above issues. We introduce here a zinc porphyrin-triazine-bodipy donor-π bridge-acceptor dye as a universal electron transfer mediator in both organic and perovskite solar cells.

Rational Design of Low Band Gap Polymers for Efficient Solar Cells with High Open-Circuit Voltage: The Profound Effect of Me and Cl Substituents with a Similar van Der Waals Radius.

Generally, low band gap material-based photovoltaic devices have reduced open circuit voltage (), and realizing the trade-off between the low band gap ( < 1.6 eV) and high (>0.9 V) could be critical to give efficient polymer solar cells, especially for high-performance semitransparent PSCs and tandem solar cells.

Regulation of Molecular Packing and Blend Morphology by Finely Tuning Molecular Conformation for High-Performance Nonfullerene Polymer Solar Cells.

The asymmetric thienobenzodithiophene (TBD) structure is first systematically compared with the benzo[1,2-:4,5-']dithiophene (BDT) and dithieno[2,3-:2',3'-']benzo[1,2-:4,5-']dithiophene (DTBDT) units in donor-acceptor (D-A) copolymers and applied as the central core in small molecule acceptors (SMAs). Specific polymers including PBDT-BZ, PTBD-BZ, and PDTBDT-BZ with different macromolecular conformations are synthesized and then matched with four elaborately designed acceptor-donor-acceptor (A-D-A) SMAs with structures comparable to their donor counterparts. The resulting polymer solar cell performance trends are dramatically different from each other and highly material-dependent, and the active layer morphology is largely governed by polymer conformation.

Facile Non-Enzymatic Electrochemical Sensing for Glucose Based on CuO-BSA Nanoparticles Modified GCE.

Transition-metal nanomaterials are very important to non-enzymatic glucose sensing because of their excellent electrocatalytic ability, good selectivity, the fact that they are not easily interfered with by chloride ion (Cl), and low cost. However, the linear detection range needs to be expanded. In this paper, CuO-bovine serum albumin (BSA) core-shell nanoparticles (NPs) were synthesized for the first time in air at room temperature by a facile and green route.