Modulation of Buried Interface by 1-(3-aminopropyl)-Imidazole for Efficient Inverted Formamidinium-Cesium Perovskite Solar Cells.

Considering the direct influence of substrate surface nature on perovskite (PVK) film growth, buried interfacial engineering is crucial to obtain ideal perovskite solar cells (PSCs). Herein, 1-(3-aminopropyl)-imidazole (API) is introduced at polytriarylamine (PTAA)/PVK interface to modulate the bottom property of PVK. First, the introduction of API improves the growth of PVK grains and reduces the Pb2+ defects and residual PbI2 present at the bottom of the film, contributing to the acquisition of high-quality PVK film. Besides, the presence of API can optimize the energy structure between PVK and PTAA, which facilitates the interfacial charge transfer. Density functional theory (DFT) reveals that the electron donor unit (R-C ═ N) of the API prefers to bind with Pb2+ traps at the PVK interface, while the formation of hydrogen bonds between the R-NH2 of API and I- strengthens the above binding ability. Consequently, the optimum API-treated inverted formamidinium-cesium (FA/Cs) PSCs yields a champion power conversion efficiency (PCE) of 22.02% and exhibited favorable stability.

Doping of ZnO Electron Transport Layer with Organic Dye Molecules to Enhance Efficiency and Photo-Stability of the Non-Fullerene Organic Solar Cells.

The solution-processed zinc oxide (ZnO) electron transport layer (ETL) always exhibits ubiquitous defects, and its photocatalytic activity is detrimental for the organic solar cell (OSC) to achieve high efficiency and stability. Herein, an organic dye molecule, PDINN-S is introduced, to dope ZnO, constructing a hybrid ZnO:PDINN-S ETL. This hybrid ETL exhibits improved electron mobility and conductivity, particularly post-light exposure. The catalytic activity of ZnO is also effectively suppressed.Consequently, the efficiency and photo-stability of inverted non-fullerene OSCs are synergistically enhanced. The devices based on PM6:Y6/PM6:BTP-eC9 active layer with ZnO:PDINN-S as ETL give impressive power conversion efficiencies (PCEs) of 16.78%/17.59%, significantly higher than those with pure ZnO as ETL (PCEs = 15.31%/16.04%). Moreover, ZnO:PDINN-S-based device shows exceptional long-term stability under continuous AM 1.5G illumination (T80 = 1130 h) , overwhelming the reference device (T80 = 455 h). In addition, Incorporating PDINN-S into ZnO alleviate mechanical stress within the inorganic lattice, making ZnO:PDINN-S ETL more suitable for the fabrication of flexible devices. Overall, doping ZnO with organic dye molecules offers an innovative strategy for developing multifunctional and efficient hybrid ETL of the non-fullerene OSCs with excellent efficiency and photo-stability.

Cation and anion optimization of ammonium halide for interfacial passivation of inverted perovskite solar cells.

Perovskite solar cell (PSC) commercialization faces intrinsic stability and efficiency challenges. N1-phenylethane-1,2-diamine hydrohalides (PNEAX) based on a new design strategy featuring cation and anion optimization have been developed for efficient interfacial passivation. Among them, PNEACl-treated devices achieved a champion efficiency of 21.01% with good stability.

Defect passivation via a multifunctional organic additive toward efficient and stable inverted perovskite solar cells.

A multifunctional group molecule, namely MATC, was first introduced into a Cs/FA-based perovskite used as an additive. An impressive PCE of 21.51% was achieved for the inverted PSCs with reduced defect states and improved perovskite film quality. Moreover, MATC passivation considerably enhanced the stability of the PSC devices.

Surface termination passivation of imidazole-based diiodide enabling efficient inverted perovskite solar cells.

N-(3-aminopropyl)-imidazole diiodide (APDI) was introduced on the upper surface of the perovskite for the first time to modulate the terminal groups. The defect traps were suppressed by binding N cations from the APDI with Pb2+. Consequently, the optimum APDI-treated device achieved a PCE of 21.41% and exhibited excellent stability.

High Conductivity, Semiconducting, and Metallic PEDOT:PSS Electrode for All-Plastic Solar Cells.

Plastic electrodes are desirable for the rapid development of flexible organic electronics. In this article, a plastic electrode has been prepared by employing traditional conducting polymer poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and plastic substrate polyethersulfone (PES). The completed electrode (Denote as HC-PEDOT:PSS) treated by 80% concentrated sulfuric acid (H2SO4) possesses a high electrical conductivity of over 2673 S/cm and a high transmittance of over 90% at 550 nm. The high conductivity is attributed to the regular arrangement of PEDOT molecules, which has been proved by the X-ray diffraction characterization. Temperature-dependent conductivity measurement reveals that the HC-PEDOT:PSS possesses both semiconducting and metallic properties. The binding force and effects between the PEDOT and PEI are investigated in detail. All plastic solar cells with a classical device structure of PES/HC-PEDOT:PSS/PEI/P3HT:ICBA/EG-PEDOT:PSS show a PCE of 4.05%. The ITO-free device with a structure of Glass/HC-PEDOT:PSS/Al4083/PM6:Y6/PDINO/Ag delivers an open-circuit voltage (VOC) of 0.81 V, short-circuit current (JSC ) of 23.5 mA/cm2, fill factor (FF) of 0.67 and a moderate power conversion efficiency (PCE) of 12.8%. The above results demonstrate the HC-PEDOT:PSS electrode is a promising candidate for all-plastic solar cells and ITO-free organic solar cells.

Predictive value of hyperglycemia on infection in critically ill patients with acute pancreatitis.

To analyze the predictive value of hyperglycemia on the extrapancreatic infection (EPI) and infected pancreatic necrosis (IPN) of severe patients with acute pancreatitis (AP). We enrolled 234 patients with acute pancreatitis admitted to the intensive care unit (ICU) of the Second Affiliated Hospital of Nanchang University from July 2017 to July 2022 for a retrospective cohort study. We collected maximum blood glucose values three times after admission to the ICU within 120 h (Glu1: 0-24 h, Glu2: 24-48 h, Glu3: 48-120 h), the levels of leucocyte, blood urea nitrogen (BUN), C-reactive protein (CRP), procalcitonin (PCT), and albumin within 24 h after admission to the ICU, and the BISAP and SIRS scores of all patients within 24 h. EPI was taken as the primary outcome indicator and IPN as the secondary outcome indicator. The accuracy of blood glucose values in predicting acute pancreatitis infection was measured by the area under the curve (AUC). A total of 56 patients appeared EPI. Univariate analysis showed that Glu3 was associated with IPN in critically ill patients with AP. Multivariate logistic regression analysis showed that Glu2, Glu3, and SIRS > 48 h were associated with EPI in critically ill patients with AP. The AUCs of Glu2 and Glu3 to predict EPI were 0.805(95%CI: 0.717-0.892) and 0.782(95%CI: 0.685-0.878), respectively, and the cutoff values were 12.60 mmol/L and 14.75 mmol/L, respectively. The AUC of Glu2 combined with Glu3 to predict EPI was 0.812(0.725-0.899). The maximum blood glucose on Day2-5 after admission to the ICU can predict infection in critically ill patients with AP. There are differences in etiology while glucose predicting infection. Patients with hypertriglyceridemia AP need to intervene blood glucose levels more actively and earlier, and control it more strictly.

Highly Stable Supercapacitors Enabled by a New Conducting Polymer Complex PEDOT:CF3 SO2(x) PSS(1-x).

Herein, a novel conducting polymer complex PEDOT:CF3 SO2(x) PSS(1-x) [denoted as S-PEDOT:CF3 SO2(x) PSS(1-x) , where PEDOT is poly(3,4-ethylenedioxythiophene) and PSS is poly(styrene sulfonate)], is fabricated with the assistance of zinc di[bis(trifluoromenthylsulfonyl) imide][Zn(TFSI)2 ] (CFE). The introduction of CF3 SO2 - group is expected to bring better stability of PEDOT:CF3 SO2 than PEDOT:PSS due to its strong Coulomb force. Electrochemical measurement shows that a high specific capacitance of 194 F cm-3 was achieved from the novel complex S-PEDOT:CF3 SO2(x) PSS(1-x) , the highest value reported so far. An all-solid-state supercapacitor assembly with a structure of S-PEDOT:CF3 SO2(x) PSS(1-x) /H2 SO4 :polyvinyl alcohol (PVA)/S-PEDOT:CF3 SO2(x) PSS(1-x) shows a record specific capacitance of 70.9 F cm-3 and a maximum energy density of 6.02 mWh cm-3 at a power density of 397 mW cm-3 . This supercapacitor device demonstrates excellent electrochemical stability with a capacitance retention rate of 98 % after 10 000 cycles and extreme air stability of 96 % capacitance retention rate after 10 000 cycles, even if the device is exposed to air over 2880 h, much better than that of PEDOT:PSS based supercapacitors. Excellent capacitance can be achieved from PEDOT:CF3 SO2(x) PSS(1-x) electrode under electrolyte-free conditions. This work provides a novel method for high performance stable supercapacitors and may pave the way for the commercialization of PEDOT based supercapacitors.

In Situ Optical Spectroscopy Demonstrates the Effect of Solvent Additive in the Formation of All-Polymer Solar Cells.

1-Chloronaphthalene (CN) has been a common solvent additive in both fullerene- and nonfullerene-based organic solar cells. In spite of this, its working mechanism is seldom investigated, in particular, during the drying process of bulk heterojunctions composed of a donor:acceptor mixture. In this work, the role of CN in all-polymer solar cells is investigated by in situ spectroscopies and ex situ characterization of blade-coated PBDB-T:PF5-Y5 blends. Our results suggest that the added CN promotes self-aggregation of polymer donor PBDB-T during the drying process of the blend film, resulting in enhanced crystallinity and hole mobility, which contribute to the increased fill factor and improved performance of PBDB-T:PF5-Y5 solar cells. Besides, the nonradiative energy loss of the corresponding device is also reduced by the addition of CN, corresponding to a slightly increased open-circuit voltage. Overall, our observations deepen our understanding of the drying dynamics, which may guide further development of all-polymer solar cells.

A two-dimensional conductive polymer/V2O5 composite with rapid zinc-ion storage kinetics for high-power aqueous zinc-ion batteries.

Vanadium oxides represent a promising cathode material for aqueous zinc ion batteries (ZIBs) owing to their abundant valences and versatile cation-storage capacities. However, the sluggish Zn2+ diffusion kinetics in the V2O5 framework and poor intrinsic conductivity result in inferior rate capability and unsatisfactory cycling performance of the V2O5 cathode, and thus limits its commercial-scale deployment. Herein, a unique conducting polymer intercalation strategy is developed to optimize the ion/electron transport simultaneously based on the rational design of the composite structure and morphology. The poly(3,4-ethylenedioxythiophene) (PEDOT) intercalated V2O5 not only remarkably enlarges the interlayer distance for facile Zn2+ diffusion, but also diminishes the electron transport resistance by the π-conjugated structure of PEDOT. Additionally, the two-dimensional (2D) morphology enables shorter ion diffusion paths as well as a larger number of exposed sites for Zn2+ insertion. As a result, the PEDOT-intercalated V2O5 (PEDOT/V2O5) exhibits a good high-rate performance (154 mA h g-1 at an ultrahigh current density of 50 A g-1) and a long-term cycling life (maintains 170 mA h g-1 even after 2500 cycles at 30 A g-1). This universal strategy provides a design principle for constructing efficient Zn2+ and electron transport pathways within cathode materials, holding great potential for the development of high-performance and durable ZIB cathodes.

Ultrasound dynamic monitoring of IVCD to guide application of CRRT in patients with renal failure combined with acute heart failure.

We explored the application value of bedside ultrasound dynamic monitoring of the inferior vena cava diameter (IVCD) and collapse with sniff (inferior vena cava collapsibility index [IVCCI]) to guide dehydration adjustment in continuous renal replacement therapy (CRRT) in patients with combined renal failure and acute heart failure. We selected 90 patients with combined renal and acute heart failure who required CRRT in the intensive care unit (ICU) from January 2019 to June 2021. According to different blood volume assessment methods, patients were randomly divided into ultrasound, experience, and control groups. We compared serum creatinine, potassium, and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels; time to improved heart failure symptoms; CRRT time; ventilator use; ICU length of stay; vasopressor use; and incidence of adverse events among groups. There were no significant differences in serum creatinine, potassium, and NT-proBNP levels in pairwise comparisons among groups before and after CRRT (P > 0.05). The time to improved heart failure symptoms, CRRT time, and ICU length of stay in the ultrasound and experience groups were lower than those in the control group; the differences were statistically significant (P < 0.05). Ventilator use duration was lower in the ultrasound and experience groups compared with the control group, with a statistically significant difference between the ultrasound and control groups (P < 0.05). The duration of vasopressor use in the ultrasound and control groups was lower than that in the experience group; the difference was statistically significant (P < 0.05). The incidence of adverse events was lower in the ultrasound group compared with the experience and control groups; the difference was statistically significant (P < 0.05). Ultrasound dynamic monitoring of IVCD and collapse with sniff can accurately assess blood volume status, and provide guidance for dehydration adjustments in CRRT and rapid relief of heart failure symptoms in patients with combined renal and acute heart failure.

Highly efficient and stable ZnO-based perovskite solar cells enabled by a self-assembled monolayer as the interface linker.

2-TA and 3-TA were introduced for the first time on the surface of ZnO, and used as SAMs for interfacial modification. A highest PCE of 20.6% was achieved for 2-TA PSCs with improved energy alignment and perovskite film quality, and reduced defect density. The modified ZnO exhibited better thermostability of the perovskite and resultant device stability.

Novel dopant-free hole transport materials enabling 20.9% efficiency in perovskite solar cells.

Two novel donor-acceptor-donor (D-A-D) type dopant-free hole transport materials (HTMs), named BDD-T and BTT-T, were developed and applied in perovskite solar cells. An impressive power conversion efficiency (PCE) of 20.9% was acquired, which is one of the highest PCEs for D-A-D type dopant-free HTMs.

Excellent rate capability supercapacitor based on a free-standing PEDOT:PSS film enabled by the hydrothermal method.

For the first time, herein, the hydrothermal method with H2SO4 as the solvent is introduced to enhance the rate capability of free-standing pristine PEDOT:PSS films. The film with a record conductivity of 3188 S cm-1 displays a rectangular characteristic at an ultrahigh scan rate of 1300 mV s-1 and a stable specific capacitance of 110 F cm-3 from 0.1 to 100 A cm-3, with a capacitance retention of up to 94.8%. The flexible supercapacitor based on the films delivers a comparable energy density of 2.96 mW h cm-3 even at a high power density of 36 685 mW cm-3. This study provides an effective method to prepare PEDOT:PSS films with outstanding electrochemical properties and potentially expand its applications in flexible devices.

Plasmon-coupled Au-nanochain functionalized PEDOT:PSS for efficient mixed tin-lead iodide perovskite solar cells.

Au nanochains with a coupled plasmonic nanostructure were first introduced into PEDOT:PSS used as a hole transport layer to fabricate mixed tin-lead PSCs. The improved electrical properties and the promotion of optical absorption contributed to a high PCE of 19.2%. Moreover, the PSCs show substantial enhancement in stability.

Progress in Synthesis of Conductive Polymer Poly(3,4-Ethylenedioxythiophene).

PEDOT is the most popularly used conductive polymer due to its high conductivity, good physical and chemical stability, excellent optical transparency, and the capabilities of easy doping and solution processing. Based on the advantages above, PEDOT has been widely used in various devices for energy conversion and storage, and bio-sensing. The synthesis method of PEDOT is very important as it brings different properties which determine its applications. In this mini review, we begin with a brief overview of recent researches in PEDOT. Then, the synthesis methods of PEDOT are summarized in detail, including chemical polymerization, electrochemical polymerization, and transition metal-mediated coupling polymerization. Finally, research directions in acquiring high-quality PEDOT are discussed and proposed.

Asymmetric Electron Acceptors for High-Efficiency and Low-Energy-Loss Organic Photovoltaics.

Low energy loss and efficient charge separation under small driving forces are the prerequisites for realizing high power conversion efficiency (PCE) in organic photovoltaics (OPVs). Here, a new molecular design of nonfullerene acceptors (NFAs) is proposed to address above two issues simultaneously by introducing asymmetric terminals. Two NFAs, BTP-S1 and BTP-S2, are constructed by introducing halogenated indandione (A1 ) and 3-dicyanomethylene-1-indanone (A2 ) as two different conjugated terminals on the central fused core (D), wherein they share the same backbone as well-known NFA Y6, but at different terminals. Such asymmetric NFAs with A1 -D-A2 structure exhibit superior photovoltaic properties when blended with polymer donor PM6. Energy loss analysis reveals that asymmetric molecule BTP-S2 with six chlorine atoms attached at the terminals enables the corresponding devices to give an outstanding electroluminescence quantum efficiency of 2.3 × 10-2 %, one order of magnitude higher than devices based on symmetric Y6 (4.4 × 10-3 %), thus significantly lowering the nonradiative loss and energy loss of the corresponding devices. Besides, asymmetric BTP-S1 and BTP-S2 with multiple halogen atoms at the terminals exhibit fast hole transfer to the donor PM6. As a result, OPVs based on the PM6:BTP-S2 blend realize a PCE of 16.37%, higher than that (15.79%) of PM6:Y6-based OPVs. A further optimization of the ternary blend (PM6:Y6:BTP-S2) results in a best PCE of 17.43%, which is among the highest efficiencies for single-junction OPVs. This work provides an effective approach to simultaneously lower the energy loss and promote the charge separation of OPVs by molecular design strategy.

Limitations and Perspectives on Triplet-Material-Based Organic Photovoltaic Devices.

Organic photovoltaic cells (OPVs) have attracted broad attention and become a very energetic field after the emergence of nonfullerene acceptors. Long-lifetime triplet excitons are expected to be good candidates for efficiently harvesting a photocurrent. Parallel with the development of OPVs based on singlet materials (S-OPVs), the potential of triplet materials as photoactive layers has been explored. However, so far, OPVs employing triplet materials in a bulk heterojunction have not exhibited better performance than S-OPVs. Here, the recent progress of representative OPVs based on triplet materials (T-OPVs) is briefly summarized. Based on that, the performance limitations of T-OPVs are analyzed. The shortage of desired triplet materials with favorable optoelectronic properties for OPVs, the tradeoff between long lifetime and high binding energy of triplet excitons, as well as the low charge mobility in most triplet materials are crucial issues restraining the efficiencies of T-OPVs. To overcome these limitations, first, novel materials with desired optoelectronic properties are urgently demanded; second, systematic investigation on the contribution and dynamics of triplet excitons in T-OPVs is necessary; third, close multidisciplinary collaboration is required, as proved by the development of S-OPVs.

Effect of Side Groups on the Photovoltaic Performance Based on Porphyrin-Perylene Bisimide Electron Acceptors.

In this work, we developed four porphyrin-based small molecular electron acceptors for non-fullerene organic solar cells, in which different side groups attached to the porphyrin core were selected in order to achieve optimized performance. The molecules contain porphyrin as the core, perylene bisimides as end groups, and the ethynyl unit as the linker. Four side groups, from 2,6-di(dodecyloxy)phenyl to (2-ethylhexyl)thiophen-2-yl, pentadecan-7-yl, and 3,5-di(dodecyloxy)phenyl unit, were applied into the electron acceptors. The new molecules exhibit broad absorption spectra from 300 to 900 nm and high molar extinction coefficients. The molecules as electron acceptors were applied into organic solar cells, showing increased power conversion efficiencies from 1.84 to 5.34%. We employed several techniques, including photoluminescence spectra, electroluminescence spectra, atomic force microscopy, and grazing-incidence wide-angle X-ray to probe the blends to find the effects of the side groups on the photovoltaic properties. We found that the electron acceptors with 2,6-di(dodecyloxy)phenyl units show high-lying frontier energy levels, good crystalline properties, and low nonradiative recombination loss, resulting in possible large phase separation and low energy loss, which is responsible for the low performance. Our results provide a detailed study about the side groups of non-fullerene materials, demonstrating that porphyrin can be used to design electron acceptors toward near-infrared absorption.

Design rules for minimizing voltage losses in high-efficiency organic solar cells.

The open-circuit voltage of organic solar cells is usually lower than the values achieved in inorganic or perovskite photovoltaic devices with comparable bandgaps. Energy losses during charge separation at the donor-acceptor interface and non-radiative recombination are among the main causes of such voltage losses. Here we combine spectroscopic and quantum-chemistry approaches to identify key rules for minimizing voltage losses: (1) a low energy offset between donor and acceptor molecular states and (2) high photoluminescence yield of the low-gap material in the blend. Following these rules, we present a range of existing and new donor-acceptor systems that combine efficient photocurrent generation with electroluminescence yield up to 0.03%, leading to non-radiative voltage losses as small as 0.21 V. This study provides a rationale to explain and further improve the performance of recently demonstrated high-open-circuit-voltage organic solar cells.