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Cast multicrystalline silicon (mc-Si) requires high quality at low cost, while fully-melted seed-assisted growth has a reasonable utilization rate but urges better initial grain control. An electrophoretic deposited quartz nucleation layer is introduced to obtain a uniform and oriented nucleation layer. Carrier recombination characterization, including photoluminescence and carrier lifetime mapping, shows that the density of recombination-active structural defects is reduced due to better grain distribution. The average conversion efficiency values of silicon particle, sprayed quartz, and deposited quartz assisted wafers are 20.52%, 20.48%, and 20.68%, respectively Moreover, deposited quartz assisted mc-Si can obtain oriented grains, which offers a potential to apply alkaline texturing on mc-Si wafers. [ABSTRACT FROM AUTHOR]

Conductive hydrogels are widely used in biosensors, human–machine interfaces, and health recording electrodes. In this study, acrylamide and gelatin were introduced into the hydrogel. A conductive double-network hydrogel with high mechanical properties was prepared using the photoinduced one-pot method. The thermally reversible physical crosslinked gelatin constructed the first network, and the covalently crosslinked polyacrylamide formed the second one. The double networks increased the cross-linking strength between hydrogels; however, they dissipated energy and enhanced the mechanical properties. The addition of potassium chloride provided electrical conductivity for the hydrogels. The prepared double-network conductive hydrogel had high mechanical properties (tensile strength >800 KPa and tensile strain >1200%), good electrical conductivity (conductivity >0.9 S m−1), and excellent sensitivity (the gauge factor reached 1.88 when the strain was 400%). Moreover, a wide range of strain sensors was demonstrated based on gelatin/PAM DN hydrogels with high stability and durability, showing potential applications in wearable and fast response electronics. [ABSTRACT FROM AUTHOR]

In this paper, we report a simple method to form conductive copper lines by scanning a single-beam femtosecond pulse laser on a plastic substrate covered with copper nitride (Cu 3 N) film. The Cu 3 N films were prepared by DC magnetron sputtering in the presence of an Ar + N 2 atmosphere at 100 °C. The influence of the laser power and scanning speed on the formed copper line width, surface features, and morphology was analyzed by means of optical microscopy, X-ray diffraction, non-contact 3D profilometer, and scanning electron microscopy. The experimental results demonstrate that low laser power and low scanning speed favor the formation of uniform and flat Cu lines. After process optimization, copper lines with a width less than 5 μm were obtained, which provides an attractive application prospect in the field of flexible electronic devices. [ABSTRACT FROM AUTHOR]

Abstract: N–In codoped ZnO thin films were prepared by ion beam enhanced deposition method (IBED) and were annealed in nitrogen and oxygen ambient after deposition. The influence of post-annealing on structure, electrical and optical properties of thin films were investigated. As-deposited and all post-annealed samples showed preferential orientation along (002) plane. Electrical property studies indicated that the as-deposited ZnO film showed p-type with a sheet resistance of 67.5kΩ. For ZnO films annealed in nitrogen with the annealing temperature increasing from 400 to 800°C, the conduction type of the ZnO film changed from p-type to n-type. However, for samples annealed in oxygen the resistance increased sharply even at a low annealing temperature of 400°C and the conduction type did not change. Room temperature PL spectra of samples annealed in N2 and in O2 showed UV peak located at 381 and 356nm, respectively. [Copyright &y& Elsevier]

Abstract: The vanadium oxide (VO2) films have been prepared on SiO2/Si substrates by using a modified Ion Beam Enhanced Deposition (IBED) method. During the film deposition, high doses of Ar+ and H+ ions have been implanted into the deposited films from the implanted beam. The resistance change of the VO2 films with temperature has been measured and the phase transition process has been observed by using the X-ray Diffraction technique. The phase transition of the IBED VO2 films starts at a low temperature of 48 °C and ends at a high temperature of 78 °C. It is found that the phase transition characteristics can be adjusted by changing the annealing temperature or the time and the phase transition characteristics of the IBED VO2 films depend on the quantity and location of argon atoms in the film matrix. [Copyright &y& Elsevier]

Abstract: N–In codoped ZnO films were prepared on Si, SiO2 and glass substrates by ion-beam enhanced deposition method and their structural, optical and electrical properties were characterized. The polycrystalline N–In codoped ZnO films deposited on Si, SiO2 and glass substrates are found to have a preferred (002) orientation, smooth surface and high density. The as-deposited ZnO film on Si substrate showed p-type with a resistivity of 2.4Ωcm. After being annealed in N2 at a temperature lower than 600°C, the ZnO films showed p-type and the lowest resistivity was 0.8Ωcm. When the annealing temperature was higher than 600°C, the ZnO films becomes n-type, and as the annealing temperature goes up, the resistivity of the N–In decreases. [Copyright &y& Elsevier]

Abstract: Since the response of microbolometer detectors depends on the modification of temperature in micromachined bridge structures, it is useful to model and simulate thermally the corresponding structures in order to predict their performance parameters. By a finite element analysis, the simulation has been performed on the stationary and transient temperature distribution within the unit element of microbolometer. The results can be used to estimate the effect of the structure, pixel size and package on the element temperature change induced by infrared radiation and thermal time constant. The influence of self-heating has been also analyzed. The readout time period for microbolometer should be designed correctly in terms of the self-heating. On the other hand, the non-uniformity distribution of microbolometer element resistance will cause an output voltage drift because of the self-heating effect. The calculation shows that when the element resistance is more than 15kΩ, the output voltage drift can be almost neglected. [Copyright &y& Elsevier]

Abstract: The plasma surface treatment and ion implantation were utilized to improve the stability of charge storage in the SiO2 film electret. It was found that the SiO2 films treated by argon plasma with the arcing at 700V for 15min, or implanted by 150keV (kilo electron volt) Ar+ with a dose of 2×1011 cm−2, after being negatively charged, showed a remnant negative potential as large as 90% of the primary value after being stored in a glass container with desiccant for 10 days. It was also found that after being negatively charged at room temperature and aged at 200–350°C for several times, the SiO2 films implanted by 150keV Ar+ had a relatively high remnant potential and it did not decay significantly even after being heated at the aging temperature of 200–350°C in room atmosphere for 60min. [Copyright &y& Elsevier]

Abstract: Different annealing conditions were adopted to anneal the vanadium oxide films prepared by modified ion beam enhanced deposition (IBED) method. An X-ray diffraction (XRD) was used to analyze the orientation of the IBED films and the resistance was tested with temperature change to measure the temperature coefficient of resistance (TCR). Experiments indicated that there existed a critical temperature for crystallization of VO2, which changed with the different deposition conditions of the IBED method. It is very difficult to obtain VO2 structure if the annealing temperature was lower than the critical temperature. If the temperature is much higher than the critical temperature or annealing time is too long, the valence of vanadium in VO2 film will easily reduce from four to low value. The TCR of the IBED VO2 polycrystalline films annealed in appropriate condition could reach higher than 4%/K. [Copyright &y& Elsevier]

VO2 polycrystalline films were directly prepared from V2O5 powder using modified ion beam enhanced deposition (IBED) method after appropriate annealing. Test results showed that IBED VO2 polycrystalline films have a single orientation, an evident phase transition, a compact structure, and favorable processing properties. The temperature coefficient of resistance (TCR) of the films was up to more than 4%/K, and the IBED VO2 films were firmly adhered to the substrate. The mechanism of the IBED films with higher TCR could be explained as following. The oxygen vacancies and grain boundaries in the films were decreased due to the IBED technology. With a single crystal orientation and dense texture, the conduction activation energy of the IBED VO2 polycrystalline films was closer to that of VO2 single crystal in the semiconductor phase as compared with VOx films formed by other methods. [Copyright &y& Elsevier]

The pick-up and transfer of easily deformable multi-layer fabrics is a challenge in the automation process of the textile industry. A transfer manipulator using interfacial adhesion forces has potential applications in the pick-up and transfer of fabrics. However, rapid adhesion and detachment cannot be achieved because of the small variability of adhesion and detachment forces between the fabric and the adhering material, which results in difficulty of picking and placing of fabric. To address this problem, in this study, an innovative pressure and strip manipulator structure is designed, utilizing the fabric gesture presented during the fabric peeling process to adjust the peel angle, and thereafter affect the adhesion force. The factors affecting the adhesion force, such as peeling speed, duration, and preload are analyzed, and a control method to regulate the adhesion force by peeling speed and the gap between the adhesion element and positioning block is proposed. Based on the interface adhesion force, the transfer manipulator can realize low-cost, high-stability, and high-efficiency fabric picking, which has good prospects for application in fabric production. [ABSTRACT FROM AUTHOR]

The most crucial initial step in the metallization process of electroplating is the local contact openings in dielectric layers. In this article, an ultraviolet picosecond laser (UV‐ps), is used to open the front and back dielectric layer of the precursor of n‐TOPCon solar cells. By changing the laser parameters and spot overlap rate, the surface morphology of laser etching under different conditions is obtained and characterized by optical microscope and scanning electron microscope. The results indicate that there are three separate laser shock zones in the dielectric layer under the action of Gaussian light spot, and the corresponding ablation mechanisms are proposed. The longitudinal distribution of B element is characterized by secondary ion mass spectrometry to explore the effect of laser on its pn junction. In addition, the electrical characterization of lifetime photoluminescence is measured and calibrated using WCT120, and this indicates that the majority of the amorphous silicon is recrystallized when applying a fast firing oven process, and this hence improve the minority carrier lifetime and implied open‐circuit voltage. The laser damage to the emitter at the laser‐ablated regions is investigated using the emitter saturation current density, J0laser extracted by WCT120. [ABSTRACT FROM AUTHOR]

The creation of hierarchical nanostructures can effectively strengthen phonon scattering to reduce lattice thermal conductivity for improving thermoelectric properties in inorganic solids. Here, we use Zn doping to induce a remarkable reduction in the lattice thermal conductivity in SnTe, approaching the theoretical minimum limit. Microstructure analysis reveals that ZnTe nanoprecipitates can embed within SnTe grains beyond the solubility limit of Zn in the Zn alloyed SnTe. These nanoprecipitates result in a substantial decrease of the lattice thermal conductivity in SnTe, leading to an ultralow lattice thermal conductivity of 0.50 W m−1 K−1 at 773 K and a peak ZT of ~0.48 at 773 K, marking an approximately 45 % enhancement compared to pristine SnTe. This study underscores the effectiveness of incorporating ZnTe nanoprecipitates in boosting the thermoelectric performance of SnTe‐based materials. [ABSTRACT FROM AUTHOR]

Efficiency reduction in perovskite solar cells (PSCs) during the magnification procedure significantly hampers commercialization. Vacuum‐flash (VF) has emerged as a promising method to fabricate PSCs with consistent efficiency across scales. However, the slower solvent removal rate of VF compared to the anti‐solvent method leads to perovskite films with buried defects. Thus, this work employs low‐toxic Lewis base ligand solvent N‐ethyl‐2‐pyrrolidone (NEP) to improve the nucleation process of perovskite films. NEP, with a mechanism similar to that of N‐methyl‐2‐pyrrolidone in FA‐based perovskite formation, enhances the solvent removal speed owing to its lower coordination ability. Based on this strategy, p–i–n PSCs with an optimized interface attain a power conversion efficiency (PCE) of 24.19% on an area of 0.08 cm2. The same nucleation process enables perovskite solar modules (PSMs) to achieve a certified PCE of 23.28% on an aperture area of 22.96 cm2, with a high geometric fill factor of 97%, ensuring nearly identical active area PCE (24%) in PSMs as in PSCs. This strategy highlights the potential of NEP as a ligand solvent choice for the commercialization of PSCs. [ABSTRACT FROM AUTHOR]

Lightweight artificial muscles with large strain and large stress output have great application prospects in robotics, rehabilitation, prosthetic, and exoskeletons. Despite the excellent performance of carbon nanotube‐based artificial muscles in recent years, their widespread use is hindered by the high manufacturing costs associated with carbon nanotubes. In this paper, the study introduces a novel approach by developing artificial muscles based on pure conductive polymer coiled yarns. This achievement is facilitated by the successful fabrication of high‐strength conductive polymer microfibers. Furthermore, the study elucidates the molecular structural changes occurring during electrochemical processes that induce a substantial radial volume expansion in the microfibers. The resultant anisotropic volume change is magnified by the coiled yarn, yielding a remarkable contractile strain exceeding 11% at a high stress of 5 MPa, equivalent to lifting loads more than 4000 times their own masses, all achieved with a low input voltage of 1 V. Additionally, these conductive polymer‐based artificial muscles exhibit hydration‐induced contraction up to 33%, with swift recovery through electrical heating, leveraging their intrinsic high conductivity. This breakthrough positions high‐performance conductive polymer microfibers as a promising cost‐effective alternative to carbon nanotubes, establishing them at the forefront of lightweight artificial muscles. [ABSTRACT FROM AUTHOR]

Perovskite nanocrystals (NCs), such as MAPbX3 (MA+ = methylammonium; X = Cl, Br, or I), have received attention owing to their excellent optoelectronic properties and ease of integrating with flexible substrates. Lanthanide ion doping is widely used as an effective strategy to enhance the optoelectronic performance of perovskite NCs. However, incorporating the lanthanide dopant and ensuring the emission stability of the perovskite NCs in high‐performance optoelectronic devices remains a major challenge. Herein, the synthesis of Eu2+‐doped MAPbBr3 NCs within the channels of SBA‐15 is presented to improve their stability. The doped MAPbBr3 NC@SBA‐15 composites exhibit significantly improved stability than that of undoped MAPbBr3 NCs. The doped MAPbBr3 NC@SBA‐15 composites exhibit moderate PL quantum yields and excellent stability under ambient conditions and UV irradiation. In addition, the MAEu0.3Pb0.7Br3 NC@SBA‐15 composite applied in white‐light‐emitting diodes (WLEDs) achieves a color rendering index of 73.5. Moreover, MAEu0.3Pb0.7Br3 NC@SBA‐15 can be combined with styrene‐ethylene‐butylene‐styrene to fabricate a flexible direct X‐ray detector, realizing a high sensitivity of 7592.2 µC Gyair−1 cm−2 and a low detection limit of <77 nGyair s−1; this is an outstanding value for a NC‐based flexible direct X‐ray detector. This work serves as a guide for the design of perovskite NCs for both WLEDs and flexible X‐ray detectors. [ABSTRACT FROM AUTHOR]

Reducing the interfacial defects between the perovskite/electron transport layer (ETL) is the key point to improving the efficient and stable performance of perovskite solar cells (PSCs). In this study, two self-assembled molecules ((aminomethyl)phosphonic acid and glycine) with different functional groups (phosphonic acid (-H2PO3) and carboxylic acid (-COOH)) were mixed to form the buried bottom interface of PSCs. The synergistic effect of -H2PO3 with its higher anchoring ability and -COOH with its fast carrier transport improved the performance of PSCs. Additionally, the SnO2 modified by mixed self-assembly molecules (M-SAM) showed a more appropriate energy level alignment, favoring charge transport and minimizing energy loss. In addition, the amine group (-NH2) on the two small molecules effectively interacted with uncoordinated Pb2+ in perovskite and improved the quality of the perovskite films. Consequently, the (FAPbI3)0.992(MAPbBr3)0.008 PSCs with M-SAM reached a PCE of 24.69% (0.08 cm2) and the perovskite modules achieved a champion efficiency of 18.57% (12.25 cm2 aperture area). Meanwhile, it still maintained more than 91% of its initial PCE after being placed in nitrogen atmosphere at 25 °C for 1500 h, which is better than that of the single-SAM and control devices. Further reference is provided for the future commercialization of perovskite with efficient and stable characteristics. [ABSTRACT FROM AUTHOR]

All‐inorganic perovskite solar cells (PSCs) have been the research focus due to their high thermal stability and proper band gap for tandem solar cells. However, their power conversion efficiency (PCE) is still lower than that of organic‐inorganic hybrid PSCs. Herein, a sacrificing dye (Rhodamine B isothiocyanate, RBITC) is developed to regulate the growth of perovskite film by in situ release of ethylammonium cations, isothiocyanate anions and benzoic acid molecules upon annealing and illumination. The ethylammonium cations can efficiently passivate surface defects. The isothiocyanate anions incorporate with uncoordinated Pb to regulate the crystallization process. The benzoic acid molecules facilitate the nucleation of the perovskite crystals. Especially, the illumination can accelerate the release of these beneficial ions/molecules to improve the quality of perovskite films further. After optimization with RBITC, a high open circuit voltage (VOC) of 1.24 V and a champion PCE of 20.95% are obtained, which are among the highest Voc and PCE values of CsPbI3 PSCs. Accordingly, the operational stability of the PSC devices is significantly improved. The results provide an efficient chemical strategy to regulate the formation of perovskite films in whole crystallization process for high performance all‐inorganic PSCs. [ABSTRACT FROM AUTHOR]

The efficiency of antimony selenide (Sb2Se3) solar cells is still limited by significant interface and deep‐level defects, in addition to carrier recombination at the back contact surface. This paper investigates the use of lithium (Li) ions as dopant for Sb2Se3 films, using lithium hydroxide (LiOH) as a dopant medium. Surprisingly, the LiOH solution not only reacts at the back surface of the Sb2Se3 film but also penetrate inside the film along the (Sb4Se6)n molecular chain. First, the Li ions modify the grain boundary's carrier type and create an electric field between p‐type grain interiors and n‐type grain boundary. Second, a gradient band structure is formed along the vertical direction with the diffusion of Li ions. Third, carrier collection and transport are improved at the surface between Sb2Se3 and the Au layer due to the reaction between the film and alkaline solution. Additionally, the diffusion of Li ions increases the crystallinity, orientation, surface evenness, and optical electricity. Ultimately, the efficiency of Sb2Se3 solar cells is improved to 7.57% due to the enhanced carrier extraction, transport, and collection, as well as the reduction of carrier recombination and deep defect density. This efficiency is also a record for CdS/Sb2Se3 solar cells fabricated by rapid thermal evaporation. [ABSTRACT FROM AUTHOR]

The design of additives mainly involves selection of functional groups with coordination relationships with defects in perovskite materials. However, it is particularly important to further adjust the geometrical configuration and electronic structure of an additive. Here, the nicotinamide (NA) and its derivative 6‐Methylnicotinamide (CNA) with electron‐donor functional groups are comparatively analyzed to investigate the effect of molecular dipole and electronic configuration on the defect passivation of perovskite absorbers and the photovoltaic properties of perovskite solar cells (PSCs). Theoretical calculations demonstrate that the CNA molecule with its large molecular dipole combine with the undercoordinated Pb2+ ions in perovskite to form a higher binding energy, which is beneficial to improve the formation energy of Pb‐related defects. Experimental characterization confirms that the CNA molecule significantly enhances the coordination effect between acylamino and undercoordinated defective Pb2+ cations, which is conducive to obtain high‐quality, low‐defect density of state, large grain size, and smooth surface perovskite absorbers. Thanks to the electronic configuration and electronic cloud distribution of CNA molecules, the PSCs yield impressive efficiency as high as 24.33% with excellent environmental storage, heat, and light stabilities. This research provides a research basis for designing additives with steric‐charge‐dependence to assist perovskite photovoltaics. [ABSTRACT FROM AUTHOR]

Highlights • Transient heat transfer characteristics of array-jet impingement is studied. • A turning point exists at H / D = 0.4, and the quenching time is divided into two region. • The quenching time decreased as the S / D ratio increased. • The flow velocity near the stagnation point region increased as H / D decreased. Abstract Numerical studies on the transient heat transfer characteristics of air-array-jet impingement, for small jet-to-plate distances and a large temperature difference between the nozzle and plate, are presented. The total mass flow rate of the jets ( m ̇) is constant at 30.34 kg/h. The nondimensional jet-to-plate distance (H / D) for a nozzle diameter (D) of 5 mm is varied from 0.2 to 1. The nondimensional hole-to-hole spacing is S / D = 5, 7, and 10, respectively. The variations in the transient heat transfer characteristics and flow velocity at different values of H / D and S / D , as a function of the cooling time, are discussed. It is found that there exists a turning point H / D = 0.4 in the effect of the transient heat transfer. As H / D is decreased, the quenching time shrinks quickly. The velocity field is proposed as an explanation for the observed transient heat transfer. In addition, an appropriate proposal is presented for designing equipments of tempering ultra-thin glass. [ABSTRACT FROM AUTHOR]

Linear D-A-D molecule with bi-(4-hexylthiophen-2-yl)vinyl(BHTV)as the conjugated π bridge between triphenylamine(TPA)donor unit(D)and 2-(4H-pyran-4-ylidene)malononitrile(PM)acceptor unit(A), TPA-BHTV-PM, has been designed and synthesized. It is applied in solution-processed organic solar cells(OSCs)as the donor material. Bi-(4-hexylthiophen-2-yl)vinyl was a π bridge containing double 4-hexyl-thienylenevinylene units and introduced into the TPA-PM-containing D-A structured molecule aiming to extend the absorbance and improve the photovoltaic properties. Through the investigation of optical and electrochemical properties of the molecule, TPA-BHTV-PM exhibits broad absorption in visible region from 350 nm to 700 nm and lower highest occupied molecular orbit(HOMO)energy level, which are fundamentals as donor in organic solar cells. The OSC devices were fabricated by spin-coating the blend solution of the TPA-BHTV-PM and PC71BM. The OSC device displayed an open circuit voltage(VOC)of 0.76 V, a short circuit current density(JSC)of 6.97 mA/cm2 and a fill factor(FF)of 38.7% which leading a power conversion efficiency(PCE)of 2.10%, under the illumination of AM.1.5, 100 mW/cm2. [ABSTRACT FROM AUTHOR]

For the current flexible actuators, the long-term performance and the reusability usually cannot meet the practical standards, and the bending direction is usually not controllable. To address this issue, a complicated manufacturing process employed to produce a flexible actuator with desirable bending property and durability. Here, we report an easy-to-prepare and low-cost fabrication method for the preparation of PVDF/PEDOT:PSS/CNTs composite film as a multifunctional actuator. This actuator can generate significant bending when exposed to acetone vapors, and the bending direction is adjustable by orienting the carbon nanotubes on the surface. Furthermore, the actuator can produce voltages up to 90 mV via the piezoelectricity of the PVDF. Overall, our approach provides a simple and promising strategy for producing self-powered devices. [ABSTRACT FROM AUTHOR]

Abstract With the rapid progress in electronics technology, there has been an increasing trend towards making electronic devices light, flexible, and wearable. This study investigates an artificial skin-like temperature sensor based on pectin and xanthan gum. The highly flexible and transparent temperature sensor that was fabricated was simple in structure and the sensitivity was 53–130%°C−1 in the temperature range of 26 °C–50 °C. The temperature-sensitive thermochromic ink that was added to the sensing film enables the visualization of the temperature-sensing process. This smart thermal sensor can be widely applied in industries as electronic skin, human body temperature measurements, and environmental monitoring, etc. Graphical abstract Image 1 Highlights • The obtained flexible temperature sensor makes the change of temperature visible. • Xanthan Gum improves mechanic properties of the flexible temperature sensor. • The temperature range of 26–50 °C makes it have a potential application in human body. [ABSTRACT FROM AUTHOR]

Antimony selenide (Sb2Se3) thin film solar cells were prepared by vapor transport deposition, and cesium chloride (CsCl2) solution was used to treat the upper interface of the device. Meanwhile, a series of characterizations of the thin film and the device were also performed. The study shows that the back contact treatment of CsCl2 solution can not only improve the carrier collection and reduce upper interface recombination of the device, but also optimize the crystallinity, surface roughness and optoelectronic performance of thin film. Based on the device structure of FTO/CdS/Sb2Se3/CsCl2/Au, a high-efficiency Sb2Se3 thin film solar cell with efficiency of 6.32% are obtained, which is 12% higher than that of the basic device. The research may provide some guidance to further development of Sb2 Se3 thin film solar cells and other similar types of semiconductor photovoltaic devices. [ABSTRACT FROM AUTHOR]

As the efficiency of perovskite solar cell has skyrocketed to as high as 25.7%, their stability has become the biggest obstacle to commercialization. Preliminary analyses suggest that additive engineering may be effective in improving both solar cell efficiency and its stability. Herein, the plant‐derived natural green additive of l‐Theanine (Thea) is selected to improve the crystal quality of the perovskite absorber and obtain high‐performance perovskite solar cells (PSCs) with ultraviolet/ozone (UV/O3) resistance. The characterization results reveal that the CO group in Thea can effectively inhibit the precipitation of metal Pb0, passivate undercoordinated Pb2+ ions, and promote the nucleation and crystallization of perovskite. In addition, the combination of the NH group and I− in the form of a hydrogen bond cooperatively reduce the probability of nonradiative recombination of photogenerated carriers and effectively improves the extraction ability of carriers from perovskite absorber. With the cooperation of CO and NH2 groups in Thea, the champion efficiency is improved from 22.29% in the control device to 24.58%. More importantly, Thea significantly alleviates the perovskite phase transition and film decomposition induced by UV/O3 treatment. The study provides exploratory research for the application of plant‐derived green additives in the UV/O3 resistance field of perovskite photovoltaics. [ABSTRACT FROM AUTHOR]

Effectively encapsulating perovskite solar cells (PSCs) to enhance the external reliability is the key towards commercialization. We herein propose a facile encapsulation method by introducing conductive ribbons and a polyethylene terephthalate (PET) backsheet on both sides of PSC. Via applying thermoplastic polyolefin (TPO) encapsulant, we implemented PSCs with fine encapsulation, enabling considerable durability in the ambient atmosphere and even with water immersion, demonstrating almost no degradation in the device output, which is ascribed to the low water vapor transmission rate as well as the high chemical stability of TPO. The operation reliability of the encapsulated cell is also significantly increased, maintaining 80% of the initial efficiency after 770 hours' light illumination in an ambient atmosphere. This novel encapsulation route provides a feasible idea for the commercial application of PSCs in the future. [ABSTRACT FROM AUTHOR]

MXene film electrodes for supercapacitors, assembled with MXene nanosheets as structure units, inevitably suffer from self-restacking, which severely restrains ion transport kinetics and results in insufficient active site utilization and poor rate capability. Herein, an in situ foaming strategy employing the accumulated gas generated during the etching of sacrificial templates, combined with the confinement between the MXene film, has been proposed to fabricate pores between stacked MXene sheets and along the vertical direction of the film. The surface chemistry of the foamed film was further modified by alkali washing treatment to replace hydrophobic –F groups with hydrophilic –OH groups to improve electrolyte penetration and introduce more active sites. The resultant porous MXene film electrode exhibits a greatly improved specific capacitance (354.1 F g−1 at 5 mV s−1) and unparalleled rate capability (with a capacitance retention of 96.1% at 2000 mV s−1). This work demonstrates a facile but efficient method for the construction of porous MXene films, simultaneously providing insights into the promising applications of MXenes. [ABSTRACT FROM AUTHOR]

Solar cell efficiency and stability are two key metrics to determine whether a photovoltaic device is viable for commercial applications. The surface termination of the perovskite layer plays a pivotal role in not only the photoelectric conversion efficiency (PCE) but also the stability of assembled perovskite solar cells (PSCs). Herein, a strong chelate coordination bond is designed to terminate the surface of the perovskite absorber layer. On the one hand, the ligand anions bind with Pb cations via a bidentate chelating bond to restrict the ion migration, and the chelate surface termination changes the surface from hydrophilic to hydrophobic. Both are beneficial to improving the long‐term stability. On the other hand, the formation of the chelating bonding effectively eliminates the deep‐level defects including PbI and Pb clusters on the Pb‐I and FA‐I terminations, respectively, as confirmed by theoretical simulation and experimental results. Consequently, the PCE is increased to 24.52%, open circuit voltage to 1.19 V, and fill factor to 81.53%; all three are among the highest for hybrid perovskite cells. The present strategy provides a straightforward means to enhance both the PCE and long‐term stability of PSCs. [ABSTRACT FROM AUTHOR]

Here, antimonene nanosheets (ANs) were prepared by electrochemical lithiation intercalation and ultrasonication process for the first time, which were introduced onto the top of perovskite precursor film as heterogeneous nucleation sites. ANs can adsorb FAI/MAI to epitaxially grow perovskite film along their (012) planes. The perovskite solar cells with ANs assisted growth show high stability and an impressive efficiency of 24.54%. [Display omitted] There are many grain boundaries and defects in polycrystalline perovskite films, resulting in sacrificed efficiency and instability for perovskite solar cells (PSCs). By regulating the growth of perovskite grains along the vertical direction through epitaxial growth, one may expect fewer grain-boundaries, effective charge transport, improved crystalline quality, and reduced defect density. However, there is still no suitable epitaxial growth substrate for perovskite. Here, we developed an electrochemical lithiation intercalation and ultrasonication method to prepare high-quality antimonene nanosheets (ANs). It is found that the perovskite film grows preferentially along the (012) planes of the ANs that have perfect lattice match with the (001) planes of the perovskite, leading to a high-quality perovskite film with a preferential orientation along the [001] direction and greatly enlarged grain size. Consequently, the oriented perovskite-based PSC achieves a remarkable PCE of 24.54% and shows an enhanced stability under ambient conditions, thermal annealing or light illumination. This work opens an effective avenue to effectively control the oriented growth of perovskite film for high-performance perovskite optoelectrical devices. [ABSTRACT FROM AUTHOR]

The development of inorganic hole‐transporting materials (HTMs) is one of the most reliable ways to improve the stability of perovskite solar cells (PSCs). However, the un‐optimal buried interfacial contacts and the defects located at the inorganic HTMs/perovskite interface restricted the device's performance. Herein, a phase‐pure CuScO2 has been synthesized and further employed as mesoporous HTM in inverted PSCs. Surprisingly, a facile pretreatment of the hole‐transport layer by a formamidine salt compensates the I− vacancy of the buried perovskite film, thus regulating the interfacial band energy alignment between the HTM and perovskite. This ion compensation strategy can not only in situ repair the ion loss and improve the built‐in electric field, but also decrease the charge injection barrier and suppress the non‐radiative interfacial recombination. Benefiting from these merits, the resulting methylammonium‐free (MA), Cs/FA‐based PSCs displays a power conversion efficiency (PCE) of 22.42% along with excellent thermal and light stability. Moreover, the pre‐buried treatment strategy can be extended to MA‐containing CsFAMA triple‐cation perovskite film, and a champion inverted device delivers a PCE of 23.11%. This study offers a new avenue to the rational design of HTMs for highly efficient and stable PSCs. [ABSTRACT FROM AUTHOR]

CsPbI2Br perovskite is known for its advantages over its organic‐inorganic hybrid counterpart including better thermal stability and appropriate bandgap for the front sub‐cell of tandem solar cell. However, its lower‐than‐satisfactory efficiency, problematic phase stability and sensitivity to moisture hinder its further advancement. Here, three kinds of glycine halides (Gly‐X: X = Cl, Br, and I) are strategically deigned to improve the performance of CsPbI2Br perovskite solar cells (PSCs). Systematic experimental and calculated results prove that a 2D/3D hybrid structure is formed, wherein the Gly‐X‐based 2D perovskite is mainly located at the CsPbI2Br grain boundaries, and the A‐sites of the 2D perovskite form strong bonds with the 3D perovskite to suppress ion migration by increasing its activation energy. As a result, a power conversion efficiency (PCE) of 17.26% was obtained with an open‐circuit voltage (VOC) of 1.33 V, which is among the best PCE values for the CsPbI2Br PSCs. In addition, the efficiency of encapsulated device decrease only by 14.1% after 340 h continuous illumination in ambient conditions, representing one of the most‐stable inorganic PSCs reported so far. This work provides important insights into designing passivating agents to address the issue of phase segregation for the development of highly stable perovskite optoelectronic devices. [ABSTRACT FROM AUTHOR]

All‐inorganic CsPbI3 perovskite presents preeminent chemical stability and a desirable band gap as the front absorber for perovskite/silicon tandem solar cells. Unfortunately, CsPbI3 perovskite solar cells (PSCs) still show low efficiency due to high density of defects in solution‐prepared CsPbI3 films. Herein, three kinds of hydrazide derivatives (benzoyl hydrazine (BH), formohydrazide (FH) and benzamide (BA)) are designed to reduce the defect density and stabilize the phase of CsPbI3. Calculation and characterization results corroborate that the carboxyl and hydrazine groups in BH form strong chemical bonds with Pb2+ ions, resulting in synergetic double coordination. In addition, the hydrazine group in the BH also forms a hydrogen bond with iodine to assist the coordination. Consequently, a high efficiency of 20.47 % is achieved, which is the highest PCE among all pure CsPbI3‐based PSCs reported to date. In addition, an unencapsulated device showed excellent stability in ambient air. [ABSTRACT FROM AUTHOR]

All‐inorganic CsPbI3 perovskite presents preeminent chemical stability and a desirable band gap as the front absorber for perovskite/silicon tandem solar cells. Unfortunately, CsPbI3 perovskite solar cells (PSCs) still show low efficiency due to high density of defects in solution‐prepared CsPbI3 films. Herein, three kinds of hydrazide derivatives (benzoyl hydrazine (BH), formohydrazide (FH) and benzamide (BA)) are designed to reduce the defect density and stabilize the phase of CsPbI3. Calculation and characterization results corroborate that the carboxyl and hydrazine groups in BH form strong chemical bonds with Pb2+ ions, resulting in synergetic double coordination. In addition, the hydrazine group in the BH also forms a hydrogen bond with iodine to assist the coordination. Consequently, a high efficiency of 20.47 % is achieved, which is the highest PCE among all pure CsPbI3‐based PSCs reported to date. In addition, an unencapsulated device showed excellent stability in ambient air. [ABSTRACT FROM AUTHOR]

Due to the low mechanical strength, poor tensile property, and inability to work under extreme conditions, hydrogels encounter obstacles in their practical applications. It was found that the Hofmeister effect could strengthen and toughen the single hydrogel networks. Herein, poly (vinyl alcohol) (PVA)/gelatin dual-network (DN) hydrogels with strong mechanical properties were prepared and improved by Hofmeister effect using Na 2 SO 4 as the salting-out solution. The hydrophilic anion SO 4 2- induced a salting-out effect, which made the interplay in PVA and gelatin stronger, and the network structure more compact and stable. Moreover, the dual-assisted effect of freeze-thaw and freezing salting-out further enhanced the mechanical properties. The as-obtained DN hydrogel had excellent overall mechanical properties with a fracture tensile strain, a tensile strength and a toughness of 1281 %, 1.12 MPa and 7.19 MJ/m3, respectively. In addition, it had the ability to withstand weights more than 5000 times its own mass. The hysteresis energy, Young's modulus, and toughness recovery of the hydrogel reached 91.21 %, 97.36 %, and 97.47 % of the original values when the interval time was 180 min. Furthermore, after treatment with ethylene glycol /H 2 O solution, the hydrogel was given high temperature resistance, anti-freezing and moisturizing properties, while maintaining its good mechanical properties in a wide temperature range. The weight remained at 84.7 % and 71.45 % of the original weight after one week at 25 °C and 12 h at 60 °C, respectively. This kind of multifunctional DN hydrogel with high mechanical properties will find wider application in the field of flexible electronic devices. [Display omitted] [ABSTRACT FROM AUTHOR]

Interestingly, the Nd3+ ions are incorporated into the crystal lattice and migrate to the CdS/Sb 2 (S,Se) 3 interface after the doping process, thereby enhancing the efficiency of the device in terms of providing a preferential crystal orientation and lower defect density. [Display omitted] • Nd3+ doping for Sb 2 (S,Se) 3 is carried out via modified hydrothermal deposition. • These ions can be incorporated into the crystal lattice. • Most of the ions migrate to the CdS/Sb 2 (S,Se) 3 interface after doping. • Photoelectrical parameters and device stability are both improved after doping. • We provide an effective doping strategy for Sb 2 (S,Se) 3 solar cells. Doping the light absorber layer of antimony chalcogenides with extrinsic ions is an effective approach for improving their photovoltaic quality. These dopant ions generally reside at positions other than the crystal lattice or form an alloy (e.g., AgSb(S,Se) 3) with a poor device performance. Therefore, incorporating such ions into an antimony chalcogenide lattice such that there is a positive influence on device quality would be highly useful. Herein, doping of Nd3+ for Sb 2 (S,Se) 3 is carried out via a modified hydrothermal deposition process. Notably, these ions are incorporated into the crystal lattice and migrate to the CdS/Sb 2 (S,Se) 3 interface after doping, which are characterized using X-ray diffraction, X-ray photoelectron spectroscopy, and time-of-flight secondary ion mass spectrometry. Nd3+ doping produces benign effects on the crystal orientation, film morphology, optoelectronic properties, and defect passivation of the Sb 2 (S,Se) 3 films. Consequently, all the photoelectrical parameters of Sb 2 (S,Se) 3 solar cells doped with Nd3+ are enhanced, delivering a remarkable efficiency of 8.24 %. Furthermore, the best device stored in air only shows a slight decrease in efficiency in the 2400-h aging test. Overall, this study provides an effective doping strategy to improve the photovoltaic quality of Sb 2 (S,Se) 3 films. [ABSTRACT FROM AUTHOR]

Light-driven monodomain liquid crystal elastomers (mLCEs) have the advantages of remote operation and local control, but the response time will increase rapidly with the increase of thickness due to the limitation of the incident light depth. In order to achieve fast response, porous AuNPs-mLCEs actuators are proposed and fabricated by a confined expansion method. The average pore size of the prepared rod-shaped porous mLCEs is 200 μm, the porosity is 46.5%, and the order parameter of mesogens is 0.41. When the diameter is 3 mm, the response time is 1.2 s at a wavelength of 532 nm and a light intensity of 2.6 W•cm−2. When the diameter increases to 10 mm, the response time only increases to 2.2 s. The contraction of porous mLCEs actuator caused by the photothermal effect enables it can not only to lift an object 321.5 times heavier than itself by contraction, but also raise-up an object 5.2 times heavier than itself by bending. This method can be used to design and manufacture various 3D porous photothermal actuators with fast response. [Display omitted] [ABSTRACT FROM AUTHOR]

For the rocket development of organic-inorganic hybrid perovskite solar cells (OIH–PSCs), the research of low-cost, dopant-free hole-transporting materials (HTMs) with high performance and stability is still an urgent problem. In this work, we synthesize organic small molecule HTM with sulfone-containing benzodithiophene (BDTOxide) as the central unit, termed BDTOxide-MTP. The synthetic cost of DBTOxide-MTP in the lab is 238 CNY/g, which is just one-fifth of the cost of the PTAA (1200 CNY/g). BDTOxide-MTP exhibits the deep highest occupied molecular orbital energy level, high hole transport mobility, and excellent passivation effect. BDTOxide-MTP is introduced into inverted OIH-PSCs as a dopant-free hole transport layer, the champion efficiency of MAPbI 3-x Cl x -based devices reaches 18.72 % with an excellent V OC of 1.13 V, while the efficiency of the control device based on PTAA is about 18.49 %. The device based on BDTOxide-MTP exhibits comparable stability to the one based on PTAA, which can maintain over 90 % of the original efficiency after 46 days in a nitrogen environment. [Display omitted] • Sulfone-containing dopant-free hole-transporting material has been synthesized. • The synthetic cost of it in the lab is 238 CNY/g. • It exhibits a deep HOMO and passivating effect. • The highest efficiency of it reaches 18.72 % with an excellent V OC of 1.13 V. [ABSTRACT FROM AUTHOR]

Thin film actuator has the advantages of simple construction and repaid responses. However, once damaged, it makes them face great challenges in terms of performance stability. Here, a self-healing thermal actuator was developed by combining a self-healing silicone elastomer with a polyimide film. The silicone elastomer with excellent self-healing and high mechanical properties was designed by triple dynamic reversible bond of hydrogen bond, oxime bond, and metal coordination bond. Polyurea groups provided a large number of cross-linking points for supramolecular hydrogen bonding, and nitrogen atoms on the oxime group form complexes with various metal ions (such as Cu2+, Zn2+, Fe3+), which can significantly improve its mechanical strength (up to 4818 kPa). Silicone elastomer exhibited fast and efficient self-healing properties (99.9% within 10 h at room temperature) based on a triple dynamic reversible bond. In addition, the actuator can be thermally driven and achieve a maximum bend of 59.9° at 100 °C. The actuator shows excellent cyclic stability in the range of 100 cycles, and can still achieve the original bending angle after healing. The realization of self-healing performance on flexible actuators provides the experimental basis for the further development of artificial muscles. [Display omitted] [ABSTRACT FROM AUTHOR]

Surprisingly, high efficiency of 9.39% Sb 2 (S,Se) 3 solar cells has been obtained with the addition of monoatomic Al 2 O 3 layer based on the adjustment crystal orientation, tailored energy band structure and reduced density of deep-level defects. [Display omitted] • Highly (hk 1)-oriented Sb 2 (S,Se) 3 film having significantly enhanced charge separation was obtained with the buried Al 2 O 3 layer. • The buried Al 2 O 3 layer can tailor the band energy structure to improved carrier collection of the device. • With the adding of monoatomic Al 2 O 3 layer, the density of surface and deep-level defect has been decreased obviously. • A 9.39 % efficiency of the device is achieved thanks to crystal orientation modulation, band alignment optimization and deep-level defects reduction. Antimony selenosulfide (Sb 2 (S,Se) 3) reveals excellent optoelectronic characteristics, positioning it as a propitious light-absorbing substance with potential applications in photovoltaic technology. However, a multitude of deep-level defects significantly limit the efficiency of Sb 2 (S,Se) 3 solar cells. In this study, the density of the surface and deep-level defects was reduced by adding a monoatomic Al 2 O 3 layer on the surface of CdS film. Compared to the as-deposited film, highly [ hk 1]-oriented Sb 2 (S,Se) 3 film having significantly enhanced charge separation was obtained. The addition of a monoatomic Al 2 O 3 layer effectively modified the energy band structure by increasing the valence band maximum and more intrinsic Sb 2 (S,Se) 3 film between n-type CdS layers and p-type spiro. This contributed to increased carrier collection and reduced carrier recombination. Ultimately, 9.39 % efficiency of the device were obtained as a result of the optimized orientation and reduced defects. Consequently, this research demonstrates an effective method for optimizing crystallographic orientation and minimizing defect density, thereby maximizing the efficiency of Sb 2 (S,Se) 3 solar cells. [ABSTRACT FROM AUTHOR]

Formamidinium methylammonium lead iodide (FAMAPbI3) perovskite has been intensively investigated as a potential photovoltaic material because it has higher phase stability than its pure FAPbI3 perovskite counterpart. However, its power conversion efficiency (PCE) is significantly inferior due to its high density of surface detects and mismatched energy level with electrodes. Herein, a bifunctional passivator, methyl haloacetate (methyl chloroacetate, (MClA), methyl bromoacetate (MBrA)), is designed to reduce defect density, to tune the energy levels and to improve interfacial charge extraction in the FAMAPbI3 perovskite cell by synergistic passivation of both CO groups and halogen anions. As predicted by modeling undercoordinated Pb2+, the MBrA shows a very strong interaction with Pb2+ by forming a dimer complex ([C6H10Br2O4Pb]2+), which effectively reduces the defect density of the perovskite and suppresses non‐radiative recombination. Meanwhile, the Br− in MBrA passivates iodine‐deficient defects. Consequently, the MBrA‐modified device presents an excellent PCE of 24.29%, an open‐circuit voltage (Voc) of 1.18 V (Voc loss ≈ 0.38 V), which is one of the highest PCEs among all FAMAPbI3‐based perovskite solar cells reported to date. Furthermore, the MBrA‐modified devices without any encapsulation exhibit remarkable long‐term stability with only 9% of PCE loss after exposure to ambient air for 1440 h. [ABSTRACT FROM AUTHOR]

Spinnable carbon nanotube arrays (spinnable CNTs) combine the multifunctional properties of CNTs and impart unique properties that are absent in disordered CNTs, such as anisotropy, high electrical conductivity, large specific surface area, super hydrophobicity, and high absorbance. Thermal chemical vapor deposition (CVD) is the main method for the preparation of spinnable CNTs. In CVD, the roles of the catalyst, substrate, temperature, gas flow rates, reaction time, and carbon sources have been studied intensively to understand their effect on the process and to identify the precise conditions for high spinnability. However, most studies have been conducted under atmospheric pressure, neglecting the crucial impact of pressure that is often discussed in semiconductor processes. To investigate the effect of pressure, we fabricated spinnable CNTs by thermal CVD in the pressure range of 1–30 kPa. Results showed that the reaction pressure not only influenced the spinnability of the CNT arrays, but also effectively reduced the optimal temperature to 540 °C, which was approximately 100 °C lower than that in the atmospheric process. In addition, the process executed at lower temperature and low pressure can suppress the leakage of flammable explosive gases, and it is more energy-saving and environmentally friendly. [Display omitted] [ABSTRACT FROM AUTHOR]

Lead halide perovskite‐based X‐ray detectors show very promising sensitivity and low detection limit, which can be used for next‐generation, room‐temperature radiation detections. It is interesting to find that the diode‐structured X‐ray detector shows very high photocurrent gain under small reversed bias voltage, which is unusual and should be investigated and understood for better device design. In this regard, a lead halide perovskite‐based X‐ray detector with the p–i–n structure is fabricated and studied. The p–i–n structured device shows abnormal and excellent photoconductor properties with high photocurrent gain factor under reverse bias. Further device simulation reveals that the ion migration and accumulation in the perovskite material are responsible for the large band‐bending at the interface, which may induce charge tunneling to reduce the contact resistance and causes the reverse‐biased device to work as a photoconductor rather than a photodiode. This finding provides a new approach to the understanding and design of high‐performance X‐ray detectors utilizing ionic semiconductors like lead halide perovskites. [ABSTRACT FROM AUTHOR]

Despite the swift development in perovskite solar cells (PSCs), suppressing the ion defects in the perovskite bulk and further extending the long‐lasting stability of the cells remain the concerned issues that are yet to be solved. Here, a symmetrical organic acceptor−donor−acceptor (A−D−A) molecule with the core architecture of indaceno[1,2‐b:5,6‐b']dithiophene (IDT) and bilateral arms of oxindole, named IDT‐OD, as a versatile defect passivation agent, is adopted to inactivate the nonradiative recombination sites in the perovskite absorber. The S element in the IDT unit and carbonyl group CO in the bilateral acceptor unit as the Lewis‐base contributes to the passivation sites that are the under‐coordinated Pb2+ cation defects and the N−H group in oxindole unit interacts with halide dangling bonds. The molecular structure with its symmetrical double arms assists the formation of a superior perovskite layer with enlarged grain size, smooth surface topography, hydrophobic property, and low density of defect state. Consequently, the corresponding PSCs with the proper IDT‐OD additive yield a remarkable increase in efficiency from 22.77% to 24.04%, along with excellent long‐term environmental and thermal stabilities. This study offers a propitious approach for ionic defect passivation engineering toward high‐performance PSCs. [ABSTRACT FROM AUTHOR]

Traditional hydrogels have been widely studied for intelligent wearable, soft mechanical, and biological medical applications due to their high water content and good biocompatibility. However, when hydrogels are used at high and low temperatures, they will inevitably face two defects: water loss and freezing. It is difficult to maintain the tensile properties, self-healing properties, and electrical conductivity of hydrogels modified to overcome these two defects. To this end, we study the mechanical properties of organogels obtained via covalently cross-linking polyacrylic acid with vinyl functionalized silicon nanoparticles (Vsnp) to form a mechanical skeleton, with dynamic reversible cross-linking network between acrylic acid and iron ions supporting the high tensile properties of the gel. The introduction of the conductive polymer polypyrrole as a conductive skeleton grafted onto gelatin can effectively avoid the issues relating to low-temperature water environment conductive gel ion transport, allowing a suitable wide temperature region for a new physically and chemically crosslinked glycerin/water organogel network structure, so as to realize organogels with balanced mechanical, electrical, and self-healing properties. The prepared organogel has good tensile properties (1140% strain), self-healing properties (3 h healing efficiency: 96%), and strong adhesion over a wide temperature range from −26 °C to 60 °C. A strain sensor based on this gel exhibits high sensitivity (GF = 13.6), low hysteresis, and a life span over a wide strain range (350%), and it can be used to monitor human tiny movements (such as swallowing, pulse, etc.). This indicates that this kind of organogel-based sensor can break through restrictions relating to the external environment and show outstanding application potential in the fields of human-machine interfaces and soft robots. [ABSTRACT FROM AUTHOR]

Phosphoric acid doped polybenzimidazole (PBI)/imidazolium-modified silsesquioxane (Im-SiO3/2) hybrid membranes with high proton conductivity at high temperature under anhydrous conditions are synthesized and characterized. The presence of Im-SiO3/2 is confirmed by FT-IR and energy-dispersive X-ray spectroscopy (EDS) mapping of silicon element. The phosphoric acid uptake and proton conductivity of the hybrid membranes increase with the Im-SiO3/2 content, and the conductivity of PBI/Im-SiO3/2-20 reaching 6.3 × 10−2 S cm−1 at 180 °C. Compared with pure PBI membranes, the introduction of Im-SiO3/2 is effective in preventing the release of the phosphoric acid component from the hybrid membranes. The properties of the prepared hybrid membranes indicate their promising prospects in anhydrous proton exchange membrane applications. [ABSTRACT FROM AUTHOR]

Boron laser-assisted doped selective emitter (LDSE) is a research hotspot in the mass production of N-type tunnel oxide passivated contact (TOPCon) silicon solar cells. Consequently, it is critical to investigate the damage and repair of laser-assisted doped selective emitter. Through simulation, a surface temperature of silicon rises to over 1414 °C during the laser-assisted doping process, which causes silicon to melt and recrystallize more quickly, and increases the solid solubility of B atoms. Meanwhile, the surface pyramid structure was partially destroyed or even collapsed. The results showed that the peak intensity of (211) crystal planes decreased while the peak intensity of (400), (311), and (220) crystal planes increased. This led to an increase in surface defects and suspension bonds, resulting in an increase in J 0,passivated up to 246.3 fA/cm2. The laser-induced damage can be successfully repaired by the post-oxidation process, reducing J 0,passivated to 45.07 fA/cm2. The Quokka simulation indicates that a laser pulse fluence of 2.78 J/cm2 can increase the efficiency of the LDSE cell by 0.31 %. It does not necessarily lead to the greater efficiency gains with higher laser pulse fluence owing to the increase in surface damage. Exploiting the laser assisted doping method with a minimal surface damage, a wide process window and low cost will be the next major challenge. • Laser assisted doping boron selective emitter is a research hotspot. • The effects of different laser pulse energy densities were investigated. • The pyramid structure was damaged with the decreased content of (211) plane. • The post-oxidation process can effectively repair the damage. • The efficiency gain was 0.31 % with the laser≈ 2.78 J/cm2. [ABSTRACT FROM AUTHOR]

The zwitterion-coated polyamidoamine (ZC-PAMAM) dendrimer with ammonium and sulfonic acid groups has been synthesized and used as filler for the preparation of PBI-based composite membranes for direct methanol fuel cells. Polybenzimidazole (PBI)/ZC-PAMAM dendrimer composite membranes were prepared by casting a solution of PBI and ZC-PAMAM dendrimer, and then evaporating the solvent. The presence of ZC-PAMAM dendrimer was confirmed by FT-IR and energy-dispersive X-ray spectroscopy (EDS) mapping of sulfur and oxygen elements. The water uptake, swelling degree, proton conductivity, and methanol permeability of the membranes increased with the ZC-PAMAM dendrimer content. For the PBI/ZC-PAMAM-20 membrane with 20 wt% of ZC-PAMAM, it shows a proton conductivity of 1.83 × 10−2 S/cm at 80 °C and a methanol permeability of 5.23 × 10−8 cm2 s−1. Consequently, the PBI/ZC-PAMAM-20 demonstrates a maximum power density of 26.64 mW cm−2 in a single cell test, which was about 2-fold higher than Nafion-117 membrane under the same conditions. [ABSTRACT FROM AUTHOR]

0.14 at% Mn-doped 0.95(Na 1/2Bi 1/2)TiO 3-0.05BaTiO 3 (0.95NBT-0.05BT) lead-free single crystals were grown by a top-seeded solution growth method (TSSG). X-ray powder diffraction measurement showed that the as-grown single crystals exhibit rhombohedral perovskite structure with apparent distortion. With the increase of temperature, successive structural phase transitions occur in the Mn-doped 0.95NBT-0.05BT single crystals. After poling, apparent dielectric anomaly is induced accompanied by the increase of the character of diffuse phase transition and the decrease of the value of dielectric constant. The Mn-doped 0.95NBT-0.05BT single crystals exhibit complex domain structure, in which micro and macro domains coexist with statistically 4 mm symmetry. The Mn-doped 0.95NBT-0.05BT lead-free single crystals exhibit excellent piezoelectric and pyroelectric properties, which will lead to promising advance in piezoelectric and pyroelectric applications. The infrared-absorption band occurred around 630.6 cm −1 can be assigned to the “stretching” normal vibration of [Na 1/2Bi 1/2]/Ti-O group. The three diffused Raman bands centered around 300, 560 and 800 cm −1 can be attributed to F2g [TiO 6] bending vibration, A1g [TiO 6] stretching vibration and “soft mode” mixed by bending and stretching vibrations. [ABSTRACT FROM AUTHOR]

The pH-responsive artificial muscle is a chemical-driven actuator without external power input. However, the low work density and adequate stability limit their practical applications. Herein, we combine the porous pH-responsive polymer with carbon fiber bundles for obtaining the coiled hybrid fiber. The coiled carbon fiber (CNF) yarn enhances the strength of hybrid fiber, and the swelling pH sensitive polymer limited to CNF provide a large stroke for hybrid fiber untwisting, resulting in an excellent work capacity and a high cycle life. When the load weight is 600 times the weight of the fiber itself, its work density reaches 287 kJ/m3. In addition, the hybrid fiber can reach a maximum stretching and contraction of 47% at a load of 400 times its own weight. The breaking stress of the obtained artificial muscle can reach more than 100 MPa. At the same time, the constructed porous polymer hydrogels improve the response rate of the artificial muscle, the response time is shortened to 10 min and do not decay in hundreds of cycles, which is further shown that the limiting effect of carbon fiber on the polymer improve the stability of the artificial muscle. It is indicated that the pH-responsive composite fibers have a high potential for use in artificial muscles, pH sensors and mechanical system. [Display omitted] [ABSTRACT FROM AUTHOR]