Styrene Sulfonate Research Articles

Bioinspired PEDOT:PSS-PVDF(HFP) flexible sensor for machine-learning-assisted multimodal recognition

Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF(HFP)) are famous materials for developing flexible sensors, their conductivity, wettability, and piezoelectricity are affected by solvents. However, challenges remain in constructing multi-signals sensor by integrating PEDOT:PSS and PVDF(HFP) through solvent induced strategy, and existing sensors lack the intelligent extraction of stimulus information and accurate recognition of multimodal applications. In this work, a bioinspired flexible sensor with strain-pressure-humidity triple-signals is constructed based on PEDOT:PSS-PVDF(HFP) film (P-P film) through the synchronous induction effect of dimethyl sulfoxide (DMSO). The P-P film with double-layer structure presents excellent conductivity (800 S/cm), piezoelectricity (output voltage, 0.13 V-0.17 V), and humidity sensitivity (response/recovery time, 1.15 s/0.42 s). This phenomenon is resulted from the conformational transition of PEDOT, β-phase content enhancement of PVDF(HFP), and removal of insulated PSS under induction effect of DMSO. The data analysis, mining, and classification are performed through machine learning, which contribute to the recognition rates for different change degree of strain, pressure, and humidity are 93.35 %, 94.59 %, and 99.95 %, respectively. Importantly, a high-precision recognition (97.46 %) for multimodal applications is achieved by intelligently extract the features of strain-pressure-humidity triple-signals. This work is beneficial for improving the performance of existing sensors and developing new high-performance materials with the assistance of machine learning.

Synergistic effect of solvent addition and temperature treatment on conductivity enhancement of MWCNTs: PEDOT:PSS composite ink for electrodes in all printed solid-state micro-supercapacitors

All solid-state micro-supercapacitors (S-MSCs) are pivotal for modern wearables as they offer rapid energy storage and release, with seamless integration into small, lightweight wearables. Developing all printed S-MSCs is a cost-effective alternative to traditional S-MSCs and can potentially revolutionize wearable energy storage technologies. This manuscript presents an innovative, substrate-friendly approach to enhance the conductivity and electrochemical performance of screen-printed electrodes for S-MSCs using multi-walled carbon nanotubes (MWCNTs): PEDOT:PSS (poly(3,4-ethylene dioxythiophene): poly(styrene sulfonate)) composite ink. By incorporating various polar solvents into the ink formulation and optimizing printing and drying parameters, a four-fold increase in conductivity (5.5 × 103 S/m) was achieved. The synergy of polar solvent addition and temperature treatment on the dielectric screening, preferential solvation, and partial segregation of PSS were identified as the principal reason behind this enhancement. The optimally formulated ink was employed to create supercapacitor electrodes, demonstrating hybrid capacitive behavior with both liquid and gel electrolytes. An impressive 97.5 % decrease in charge transfer resistance (RCT) and a corresponding increase in areal capacitance and energy density were observed for these supercapacitors due to the segregation of PEDOT and PSS achieved by the synergistic effect. All printed S-MSCs were also fabricated with an impressive areal capacitance of 9.82 mF/cm2 @ 60 µA/cm2 and areal energy density of 1.964 µWh/cm2 at an areal power density of 63 µW/cm2. The fabricated S-MSCs exhibited impeccable capacitance retention of 99.7 % after 6,000 operation cycles and impressive stability upto 10,000 bending cycles, making them promising energy storage solutions for flexible and wearable devices.

Carbon nanotube-grid infrared transparent electrodes for flexible electrochromic devices with visible to mid-infrared dual-band modulation

Flexible mid-infrared electrochromic devices (MIR-ECDs) have attracted wide attention due to the growing demands for thermal camouflage and body comfort. However, the normal conductive films (e.g., indium tin oxide/polyethylene terephthalate (ITO/PET) films) are unsuitable for MIR-ECDs due to low infrared transmittance. Herein, the infrared transparent carbon nanotube (CNT) grid films were prepared by designing the grid structure. The infrared transmittance of CNT grid film could reach 72 %; meanwhile, the visible transmittance could reach 75 %. The CNTs exhibited infrared modulation under different voltages due to the doping/de-doping of ions in electrolytes into the CNT network. The flexible electrochromic devices with visible to mid-infrared dual-band modulation were prepared by using CNT grid film as the electrode and poly (3,4 ethylenedioxythiophene):poly (styrene sulfonate) (PEDOT:PSS) as the electrochromic layer, which could realize the infrared synergistic modulation of PEDOT:PSS and CNT grid in the mid-infrared range and reversible color changes between light blue and dark blue in the visible range, showing promising applications in adaptive camouflage and thermal management.

Ion-Specific Effects on Ion and Polyelectrolyte Solvation.

Ion-specific effects on aqueous solvation of monovalent counter ions, Na , K , Cl , and Br , and two model polyelectrolytes (PEs), poly(styrene sulfonate) (PSS) and poly(diallyldimethylammonium) (PDADMA) were here studied with ab initio molecular dynamics (AIMD) and classical molecular dynamics (MD) simulations based on the OPLS-aa force-field which is an empirical fixed point-charge force-field. Ion-specific binding to the PE charge groups was also characterized. Both computational methods predict similar response for the solvation of the PEs but differ notably in description of ion solvation. Notably, AIMD captures the experimentally observed differences in Cl and Br anion solvation and binding with the PEs, while the classical MD simulations fail to differentiate the ion species response. Furthermore, the findings show that combining AIMD with the computationally less costly classical MD simulations allows benefiting from both the increased accuracy and statistics reach.

Enhanced Microstructural Uniformity in Sulfuric-Acid-Treated Poly(3,4-Ethylenedioxythiophene):Poly(Styrene Sulfonate) Films Using Raman Map Analysis.

Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) films have emerged as potential alternatives to indium-tin oxide as transparent electrodes in optoelectronic devices because of their superior transparency, flexibility, and chemical doping stability. However, pristine PEDOT:PSS films show low conductivities because the insulating PSS-rich domains isolate the conductive PEDOT-rich domains. In this study, the conductivities and corresponding spatially resolved Raman properties of PEDOT:PSS thin films treated with various concentrations of H2SO4 are presented. After the PEDOT:PSS films are treated with the H2SO4 solutions, their electrical conductivities are significantly improved from 0.5 (nontreated) to 4358 S cm-1 (100% v/v). Raman heat maps of the peak shifts and widths of the Cα═Cβ stretching mode are constructed. A blueshift and width decrease of the Cα═Cβ Raman mode in PEDOT are uniformly observed in the entire measurement area (20 × 20 µm2), indicating that microstructural transitions are successfully accomplished across the area from the coiled to linear conformation and high crystallinity upon H2SO4 treatment. Thus, it is proved that comprehensive Raman map analysis can be easily utilized to clarify microstructural properties distributed in large areas induced by various dopants. These results also offer valuable insights for evaluating and optimizing the performance of other conductive thin films.

Synthesis and Characterization of Nanocomposite Hydrogels Based on Poly(Sodium 4-Styrene Sulfonate) under Very-High Concentration Regimen of Clays (Bentonite and Kaolinite).

The aim of this work was to synthesize and study the functional properties of polymer-clay nanocomposite (PCNCs) based on poly(sodium 4-styrene sulfonate) (NaPSS) and two types of clay in the dispersed phase: bentonite and kaolinite, in order to advance in the development of new geomimetic materials for agricultural and environmental applications. In this study, the effect of adding high concentrations of clay (10-20 wt. %) on the structural and functional properties of a polymer-clay nanocomposite was evaluated. The characterization by infrared spectroscopy made it possible to show that the PCNCs had a hybrid nature structure through the identification of typical vibration bands of the clay matrix and NaPSS. In addition, scanning electron microscopy allowed us to verify its hybrid composition and an amorphous particle-like morphology. The thermal characterization showed degradation temperatures higher than ~300 °C with Tg values higher than 100 °C and variables depending on the clay contents. In addition, the PCNCs showed a high water-retention capacity (>2900%) and cation exchange capacity (>112 meq/100 g). Finally, the results demonstrated the ability of geomimetic conditioners to mimic the structure and functional properties of soils, suggesting their potential application in improving soil quality for plant growth.

Organic photoelectrochemical transistor biosensor for the detection of histone deacetylase Sirt1 based on the cleavage of deacetylated peptide chain by recombinant lysine endopeptidase

As a new analytical method, organic photoelectrochemical transistor (OPECT) biosensor has a good application in biological analysis. In this experiment, a novel organic photoelectrochemical transistor (OPECT) biosensor was successfully prepared for the specific and sensitive detection of histone deacetylase Sirt1, in which Bi-MOF@BiVO4 was served as the photosensitive material, and the hydrolysis reaction of Recombinant Lysine Endopeptidase (RLys-C) to the deacetylated short peptide was used as the gate regulatory unit. The construction of Bi-MOF@BiVO4 heterojunction improved the photovoltaic property of BiVO4, which in turn enhanced the sensitive modulation of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) -based OPECT. In addition, it was found that acetylated lysine had a significant inhibitory effect on RLys-C enzyme activity, and thus the attempt was made to use the enzymatic cleavage of deacetylated peptides by RLys-C to improve the detection signal. Under the specific cleavage of the deacetylated peptide chain by RLys-C, the dielectric properties of the gate surface are changed, and the modulation response of OPECT was caused under zero gate bias. By monitoring the channel current, the detection of the target molecule Sirt1 was realized. The concentration range of Sirt1 enzyme detected by the sensor was 0.001–10 nM, and there was a linear relationship between the logarithm and the photocurrent signal. The detection limit was 0.395 pM (3σ). In addition, the effects of sodium acetate and sodium butyrate on Sirt1 enzyme activity were studied by OPECT bioassay, which is expected to become a general method for screening Sirt1 enzyme inhibitors.

Commitment of human mesenchymal stromal cells towards ACL fibroblast differentiation upon rAAV-mediated FGF-2 and TGF-β overexpression using pNaSS-grafted PCL films.

Despite various clinical options, human anterior cruciate ligament (ACL) lesions do not fully heal. Biomaterial-guided gene therapy using recombinant adeno-associated virus (rAAV) vectors may improve the intrinsic mechanisms of ACL repair. Here, we examined whether poly(sodium styrene sulfonate)-grafted poly(ε-caprolactone) (pNaSS-grafted PCL) films can deliver rAAV vectors coding for the reparative basic fibroblast growth factor (FGF-2) and transforming growth factor beta (TGF-β) in human mesenchymal stromal cells (hMSCs) as a source of implantable cells in ACL lesions. Efficient and sustained rAAV-mediated reporter (red fluorescent protein) and therapeutic (FGF-2andTGF-β) gene overexpression was achieved in the cells for at least 21 days in particular with pNaSS-grafted PCL films relative to all other conditions (up to 5.2-fold difference). Expression of FGF-2 and TGF-β mediated by rAAV using PCL films increased the levels of cell proliferation, the DNA contents, and the deposition of proteoglycans and of type-I and -III collagen (up to 2.9-fold difference) over time in the cells with higher levels of transcription factor expression (Mohawk, Scleraxis) (up to 1.9-fold difference), without activation of inflammatorytumor necrosis alpha especially when using pNaSS-grafted PCL films compared with the controls. Overall, the effects mediated by TGF-β were higher than those promoted by FGF-2, possibly due to higher levels of gene expression achieved upon rAAV gene transfer. This study shows the potential of using functionalized PCL films to apply rAAV vectors for ACL repair.

Highly transparent and stretchable multi-layered capacitive film sensor with flexible dot and micro-pillar array for small pressure sensing

The research aim is to develop multilayered capacitive film pressure sensors with dot and micro-pillar array, having high transparency, sensitivity, and flexibility by utilizing polydimethylsiloxane (PDMS) and the conductive polymer, poly(3,4-ethylenedioxythiophene): poly (styrene sulfonate) (PEDOT: PSS)" as the primary components. The results reveal that the transmittance values of the multilayered capacitive film sensors with dot array vary with their thickness, achieving values of 76.39 %, 72.06 %, and 65.39 % at a center wavelength of 550 nm and demonstrating the effective capacitive sensing response in the pressure range of 0–750 kPa. Notably, the micro-pillar array multilayered capacitive film sensor shows high sensitivity of 0.025 kPa−1 in the pressure range of 0–100 kPa and a clear trend of capacitance change around 60 kPa. It achieves the highest sensitivity of 0.05 kPa−1 within the 0–10 kPa pressure range. The stability of the multilayered capacitive film sensor is examined by applying compressive forces of 0.5 N, 1.0 N, and 1.5 N in a suspended state, resulting in a maximum rate of change reaching 104.7 % compared to the initial capacitance value. Additionally, the multilayered capacitive film sensors demonstrate good stability under cyclic pressures of 0.5 N, 1.0 N, and 1.5 N. The novel multilayered capacitive film sensor offers specific promising potentials for various applications in the fields of wearable, medical devices, and human-machine interfaces.

Synthesis and Evaluation of Plugging Gel Resistant to 140 °C for Lost Circulation Control: Effective Reduction in Leakage Rate in Drilling Process.

Gel plugging agents have become one of the preferred methods for plugging in complex and severe loss conditions during drilling due to their good adaptability to loss channels. To address the common issue of poor temperature resistance in gel-based plugging agents, high-temperature-resistant gel plugging materials were synthesized through the molecular design of polymers, modifying existing agents. Based on the temperature and salt resistance of the aqueous solution of an acrylamide (AM)/N-vinylpyrrolidone (NVP) binary copolymer, temperature-resistant monomer sodium styrene sulfonate (SSS) was introduced and reacted in a polyvinyl alcohol (PVA) aqueous solution. Using ammonium persulfate (APS) as an initiator and crosslinking with N,N-methylenebisacrylamide (MBA), a gel plugging material resistant to 140 °C was synthesized. The structure, thermal stability, water absorption and expansion, and plugging performance of the gel were studied through hot rolling aging, thermogravimetric analysis, infrared spectroscopy, electron microscopy scanning, sand bed experiments, and drag reduction experiments. The results show that the gel material has good thermal stability and water absorption and expansion at 140 °C, and its temperature-resistant plugging performance is excellent, significantly slowing down the loss rate of drilling fluid. This provides a basis for the further development of gel materials.

Optimizing charge transport in hybrid GaN-PEDOT:PSS/PMMADevice for advanced application

Organic–inorganic hybrid light-emitting devices have garnered significant attention in the last few years due to their potential. These devices integrate the superior electron mobility of inorganic semiconductors with the remarkable optoelectronic characteristics of organic semiconductors. The inquiry focused on analyzing the optical and electrical properties of a light-emitting heterojunction that combines p-type GaN with organic materials (PEDOT, PSS, and PMMA). This heterojunction is an organic–inorganic hybrid. The procedure entailed utilizing a spin-coating technique to apply a layer of either poly(methyl methacrylate) (PMMA) or a mixture of PMMA and poly(3,4ethylenedioxythiophene)-poly(styrene sulfonate) (PEDOT: PSS) onto an indium tin oxide (ITO) substrate. Subsequently, different Nd:YAG laser pulses (200, 250, and 300 pulses) were used to administer a GaN inorganic layer onto the prepared organic layer using a pulsed laser deposition approach. Subsequently, the thermal evaporation technique was employed to deposit an aluminum electrode on the top of the organic and inorganic layers, while laser pulses were fine-tuned for optimal performance. The Hall effect investigation verifies the p-type conductivity of the GaN material. The electroluminescence studies confirmed the production of blue light by the GaN-based devices throughout a range of voltage situations, spanning from 45 to 72 V.

Modeling of Electrochemical Impedance of Fuel Cell Based on Novel Nanocomposite Membrane

The new hybrid composite materials for PEM fuel cell were synthesized by the UV polymerization of acrylic monomers (acrylonitrile, acrylic acid, ethylene glycol dimethacrylate) and a sulfo aromatic monomer, i.e., sodium styrene sulfonate, and the tetraethoxysilane/3-methacryloxypropyltrimethoxysilane-based sol–gel system. By means of X-ray spectroscopy, the fractal structure of the obtained materials was characterized. Proton conductivity and viscoelasticity of the obtained materials were determined depending on the content of the inorganic component in nanocomposites. Based on impedance studies, an equivalent scheme is proposed that successfully describes the proton conductivity in the synthesized composite’s electrolyte membranes.

Synthesis and Characterization of Maghemite Nanoparticles Functionalized with Poly(Sodium 4-Styrene Sulfonate) Saloplastic and Its Acute Ecotoxicological Impact on the Cladoceran Daphnia magna.

Using a modified co-precipitation method, 11(2) nm γ-Fe2O3 nanoparticles functionalized with PSSNa [Poly(sodium 4-styrenesulfonate)] saloplastic polymer were successfully synthesized, and their structural, vibrational, electronic, thermal, colloidal, hyperfine, and magnetic properties were systematically studied using various analytic techniques. The results showed that the functionalized γ-Fe2O3/PSSNa nanohybrid has physicochemical properties that allow it to be applied in the magnetic remediation process of water. Before being applied as a nanoadsorbent in real water treatment, a short-term acute assay was developed and standardized using a Daphnia magna biomarker. The ecotoxicological tests indicated that the different concentrations of the functionalized nanohybrid may affect the mortality of the Daphnia magna population during the first 24 h of exposure. A lethal concentration of 533(5) mg L-1 was found. At high concentrations, morphological changes were also seen in the body, heart, and antenna. Therefore, these results suggested the presence of alterations in normal growth and swimming skills. The main changes observed in the D. magna features were basically caused by the PSSNa polymer due to its highly stable colloidal properties (zeta potential > -30 mV) that permit a direct and constant interaction with the Daphnia magna neonates.

Ag:PSS polyelectrolyte/PTB7 bilayers as efficient hole transport layers for perovskite solar cells

By virtue of the exceptional optical and electrical features of organic-inorganic lead-halide perovskites, the power conversion efficiency (PCE) of perovskite solar cells (PeSCs) has surpassed that of commercialized single junction silicon solar cells. Although PeSCs have demonstrated exceptional efficiency, there is still room for improvement to approach the theoretical Shockley-Queisser limit. Additionally, there is a need for the development of cost-effective strategies to produce high-performance devices, enabling PeSCs to fulfill their potential as a widely adopted and sustainable energy source.Considering this, in this work, we’ve developed a polyelectrolyte (silver poly(styrene sulfonate (PSS)) (Ag:PSS) hole transport layer (HTL), and investigated it in combination with a conjugated polymer,poly[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b]-dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl] (PTB7) as a bilayer HTL. Ag:PSS alone performs poorly due to mismatched energy levels at the anode interface, however, when PTB7 is used in combination with Ag:PSS, effective extraction and transport of carriers towards the anode is achieved. PeSCs with optimized bilayer HTLs (Ag:PSS/PTB7) gave PCEs of up to 17.09 %, higher than that of the Ag:PSS alone (reference device 12.13 %) which can be attributed to improved interfacial energetics at the HTL/perovskite interface.

Perovskite photodetector-based laser absorption spectroscopy for gas detection

A gas detection method based on CH3NH3PbI3 (MAPbI3) and poly (3,4-ethylenedioxythiophene): poly (4-styrene sulfonate) (PEDOT:PSS) composite photodetectors (PDs) is proposed. The operation of the PD primarily relies on the photoelectric effect within the visible light band. Our study involves constructing a gas detection system based on tunable diode laser spectroscopy (TDLAS) and MAPbI3/PEDOT:PSS PD, and O2 was selected as the target analyte. The system has achieved a minimum detection limit (MDL) of 0.12% and a normalized noise equivalent absorption coefficient (NNEA) of 8.83 × 10−11 cm-1⋅W⋅Hz-1/2. Furthermore, the Allan deviation analysis results indicate that the system can obtain sensitivity levels as low as 0.058% over an averaging time of 328 seconds. This marks the first use of MAPbI3/PEDOT:PSS PD in gas detection based on TDLAS. Despite the detector's performance leaves much to be desired, this innovation offers a new approach to developing spectral based gas detection system.

Poly(3,4-Ethylenedioxythiophene)/Functional Gold Nanoparticle films for Improving the Electrode-Neural Interface.

Implantable neural electrodes are indispensable tools for recording neuron activity, playing a crucial role in neuroscience research. However, traditional neural electrodes suffer from limited electrochemical performance, compromised biocompatibility, and tentative stability, posing great challenges for reliable long-term studies in free-moving animals. In this study, a novel approach employing a hybrid film composed of poly(3,4-ethylenedioxythiophene)/functional gold nanoparticles (PEDOT/3-MPA-Au) to improve the electrode-neural interface is presented. The deposited PEDOT/3-MPA-Au demonstrates superior cathodal charge storage capacity, reduced electrochemical impedance, and remarkable electrochemical and mechanical stability. Upon implantation into the cortex of mice for a duration of 12weeks, the modified electrodes exhibit notably decreased levels of glial fibrillary acidic protein and increased neuronal nuclei immunostaining compared to counterparts utilizing poly(3,4-ethylenedioxythiophene)/poly(styrene sulfonate). Additionally, the PEDOT/3-MPA-Au modified electrodes consistently capture high-quality, stable long-term electrophysiological signals in vivo, enabling continuous recording of target neurons for up to 16weeks. This innovative modification strategy offers a promising solution for fabricating low-impedance, tissue-friendly, and long-term stable neural interfaces, thereby addressing the shortcomings of conventional neural electrodes. These findings mark a significant advancement toward the development of more reliable and efficacious neural interfaces, with broad implications for both research and clinical applications.

Multi-Functional PEDOT:PSS as the Efficient Perovskite Solar Cells.

Poly(3,4-ethylenedioxythiophene) (PEDOT), particularly in its complex form with poly(styrene sulfonate) (PEDOT:PSS), stands out as a prominent example of an organic conductor. Renowned for its exceptional conductivity, substantial light transmissibility, water processability, and remarkable flexibility, PEDOT:PSS has earned its reputation as a leading conductive polymer. This study explores the unique effects of two additives, Bisphenol A diglycidyl ether (DGEBA) and Dimethyl sulfoxide (DMSO), on the PSS component of PEDOT:PSS films are shown. Both additives induce grain size growth, while DGEBA makes the PEDOT:PSS layer hydrophobic, which acts as a passivation to protect the perovskite layer, which is vulnerable to moisture. The other additive, DMSO, separates the PSS groups, resulting in increased conductivity through the free movement of holes. With these multi-modified p-type PEDOT:PSS, theITO/M-PEDOT:PSS/Perovskite/PCBM/Ag structured reverse structure solar cell has improved the power conversion efficiency (PCE) from 15.28% to 17.80% compared to the control cell with conventional PEDOT:PSS. It also maintains 90% for 500h at 60°C and 300h at 1 sun illuminating conditions.

Fabrication of Uniform Anionic Polymeric Nanoplatelets as Building Blocks for Constructing Conductive Hydrogels with Enhancing Conductive and Mechanical Properties.

Conductive hydrogels play a crucial role in advancing technologies like implantable bioelectronics and wearable electronic devices, owing to their favorable conductivity and appropriate mechanical properties. Here, a novel bottom-up approach is reported for crafting conductive nanocomposite hydrogels to achieve enhancing conductive and mechanical properties. In this approach, new poly(ɛ-caprolactone)-based block copolymers with sulfonic groups are first synthesized and self-assembled into uniform polyanionic nanoplatelets. Subsequently, these negatively charged nanoplatelets, with sulfonic groups on the surface, are employed as nanoadditives for the polymerization of 3,4-ethylenedioxythiophene (EDOT), resulting in poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS)/nanoplatelet complex with 3.8 times enhanced electrical conductivity compared with their counterparts prepared using block copolymers (BCPs). Blending the (PEDOT:PSS)/nanoplatelet complex with calcium alginate, nanocomposite hydrogels are successfully prepared. In comparison with hydrogels with (PEDOT:PSS)/BCP complexes prepared by a top-down method, the nanocomposite hydrogels are found to show twice as strong mechanical strength and 1.6 times higher conductivity. This work provides valuable insights into the bottom-up construction of conductive hydrogels for bioelectronics using well-controlled polymeric nanoplatelets.

Enhanced Efficiency and Stability of Sky Blue Perovskite Light-Emitting Diodes via Introducing Lead Acetate.

All-inorganic metal halide perovskite is promising for highly efficient and thermally stable perovskite light-emitting diodes (PeLEDs). However, there is still great room for improvement in the film quality, including low coverage and high trap density, which play a vital role in achieving high-efficiency PeLEDs. In this work, lead acetate (Pb(Ac)2) was introduced into the perovskite precursor solution as an additive. Experimental results show that perovskite films deposited from a one-step anti-solvent free solution process with increased surface coverage and reduced trap density were obtained, leading to enhanced photoluminescence (PL) intensity. More than that, the valence band maximum (VBM) of perovskite films was reduced, bringing about a better energy level matching the work function of the hole-injection layer (HIL) poly (3,4-ethylenedioxythiophene)-poly (styrene sulfonate) (PEDOT: PSS), which is facilitated for the hole injection, leading to a decrease in the turn-on voltage (Vth) of PeLEDs from 3.4 V for the control device to 2.6 V. Finally, the external quantum efficiency (EQE) of the sky blue PeLEDs (at 484 nm) increased from 0.09% to 0.66%. The principles of Pb(Ac)2 were thoroughly investigated by using X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). This work provides a simple and effective strategy for improving the morphology of perovskite and therefore the performance of PeLEDs.

Conductive dual-network hydrogel-based multifunctional triboelectric nanogenerator for temperature and pressure distribution sensing

Conductive hydrogels are gaining attention in flexible electronics due to their high electrical conductivity and stretchable mechanical properties. Utilizing conductive hydrogels as electrodes in triboelectric nanogenerators (TENG) offers a promising avenue for developing versatile, flexible devices. However, the preparation of a multifunctional hydrogel-based TENG remains a challenging task. Here, a dual-network hydrogel TENG is denoted as DNH-TENG. It comprises poly(3,4-ethylenedioxythiophene): poly (styrene sulfonate) (PEDOT: PSS)/poly (vinyl alcohol) (PVA)/carboxylated multi-walled carbon nanotube (MWCNT-COOH) and offers the advantages of straightforward fabrication, versatile applications, and efficient output performance. Preparing a double network by combining a conductive network with a soft network improves the tensile properties but reduces its conductivity significantly. Further doping MWCNT-COOH with the dual-network leads to a conjugation effect and hydrogen bonding. This enhancement fortifies the hydrogel structure and augments the electrode's conductivity and mechanical properties. In single electrode mode, the DNH-TENG exhibits a short-circuit current of 16.2 μA, a transfer charge of 97.3 nC, and an open-circuit voltage of 270.5 V. Furthermore, DNH-TENG exhibits an impressive stretchability, allowing it to be extended to 566%. Using DNH-TENG's exceptional stretchability and ultrahigh sensitivity to mechanical and temperature stimuli, we designed DNH-TENG-based sensor arrays to showcase temperature and pressure distribution monitoring applications.