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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]

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]

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]

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]

Combining the merits of battery and supercapacitor into a single device represents a major scientific and technological challenge. From a design perspective, electrode material plays a key role in the device and the fundamental difficulty lies in incorporating a high density of active sites into a stable material with excellent charge transfer kinetics. Here, the synthesis is reported of a nearly full‐oxygen‐functionalized 2D conductive transition metal carbide (Ti3C2Oy) with ultrahigh density of Ti─O/═O redox‐active sites by nucleophilic substitution and in situ oxidation under the presence of a proper electrophilic reagent (K+). The fabricated electrode delivered exceptionally high gravimetric and volumetric capacitance (1,082 F g−1 and 3,182 F cm−3 in a potential window of 0.85 V, approximating the theoretical capacity of many transition metal oxides), fast charging/discharging in tens of seconds across a wide range of temperature (−70 to 60 °C), and excellent structural and chemical stability. These promising results provide avenues for the development of high‐energy, high‐power storage devices as well as electromagnetic shielding, and electronic and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Yarn artificial muscles offer an exciting avenue to replicate the extraordinary efficiency of biological muscles, converting chemical energy directly into mechanical work. Nevertheless, realizing the chemical‐mechanical energy conversion has posed significant challenges. In this study, a novel approach for harnessing direct catalysis to power yarn artificial muscles within a one‐compartment aqueous system is introduced. This research distinguishes itself through an innovative actuation mechanism using nanoscale catalytic particles. These nanoparticles synthesized and integrated onto the yarn surface act as a chemical trigger for muscle actuation. Notably, the resulting yarn muscle demonstrates a reversible tensile stroke of nearly 4% in ≈20 s. By bridging the gap between chemical catalysis and mechanical performance, this study paves the way for innovative applications in fields ranging from robotics to biomedical devices. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) transition-metal carbide Ti3C2TX (MXene) possesses good electrical conductivity, high specific surface areas and metal oxide-like surfaces, which make it ideal for application in supercapacitors with both high energy density and power density. However, similar to other 2D materials, the issue of self-stacking leads to narrower ion-transport channels, along with a drastic reduction in active sites, thus severely limiting the performance of MXene-based electrodes. To address this problem, this work proposes to introduce one-dimensional (1D) reduced graphene oxide (rGO) nanoribbons as spacers between MXene nanosheets to construct a composite structure for inhibiting self-stacking. As expected, owing to the steric effect and high aspect ratio of rGO nanoribbons, the fabricated MXene/rGO hybrid electrode, with the addition of 5 wt% graphene oxide (GO), exhibits a greatly improved specific capacitance (397.4 F g−1 at 5 mV s−1) and an unparalleled rate capability (with a capacitance retention of 52.9% at 2000 mV s−1). This work sheds significant light on the development of MXene-based materials for advanced energy storage devices. [ABSTRACT FROM AUTHOR]

Various isomers have been developed to regulate the morphology and reduce defects in state‐of‐the‐art perovskite solar cells (PSCs). To insight the structure‐function‐effect correlations for the isomerization of thiourea derivatives on the performance of the PSCs, we developed two thiourea derivatives [(3,5‐dichlorophenyl)amino]thiourea (AT) and N‐(3,5‐dichlorophenyl)hydrazinecarbothioamide (HB). Supported by experimental and calculated results, it was found that AT can bind with undercoordinated Pb2+ defect through synergistic interaction between N1 and C=S group with a defect formation energy of 1.818 eV, which is much higher than that from the synergistic interaction between two −NH− groups in HB and perovskite (1.015 eV). Moreover, the stronger interaction between AT and Pb2+ regulates the crystallization process of perovskite film to obtain a high‐quality perovskite film with high crystallinity, large grain size, and low defect density. Consequently, the AT‐treated FACsPbI3 device engenders an efficiency of 25.71 % (certified as 24.66 %), which is greatly higher than control (23.74 %) and HB‐treated FACsPbI3 devices (25.05 %). The resultant device exhibits a remarkable stability for maintaining 91.0 % and 95.2 % of its initial efficiency after aging 2000 h in air condition or tracking at maximum power point for 1000 h, respectively. [ABSTRACT FROM AUTHOR]

Various isomers have been developed to regulate the morphology and reduce defects in state‐of‐the‐art perovskite solar cells (PSCs). To insight the structure‐function‐effect correlations for the isomerization of thiourea derivatives on the performance of the PSCs, we developed two thiourea derivatives [(3,5‐dichlorophenyl)amino]thiourea (AT) and N‐(3,5‐dichlorophenyl)hydrazinecarbothioamide (HB). Supported by experimental and calculated results, it was found that AT can bind with undercoordinated Pb2+ defect through synergistic interaction between N1 and C=S group with a defect formation energy of 1.818 eV, which is much higher than that from the synergistic interaction between two −NH− groups in HB and perovskite (1.015 eV). Moreover, the stronger interaction between AT and Pb2+ regulates the crystallization process of perovskite film to obtain a high‐quality perovskite film with high crystallinity, large grain size, and low defect density. Consequently, the AT‐treated FACsPbI3 device engenders an efficiency of 25.71 % (certified as 24.66 %), which is greatly higher than control (23.74 %) and HB‐treated FACsPbI3 devices (25.05 %). The resultant device exhibits a remarkable stability for maintaining 91.0 % and 95.2 % of its initial efficiency after aging 2000 h in air condition or tracking at maximum power point for 1000 h, respectively. [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]

Antimony selenide (Sb2Se3) is regarded as a next‐generation material for high‐efficiency photovoltaic applications due to its favorable bandgap, high absorption coefficient, carrier mobility, and stability. Nonetheless, cadmiun sulfide (CdS) has low short‐wavelength transmittance, which limits photon utilization, and the suboptimal band alignment in the CdS/Sb2Se3 heterojunction causes significant interface recombination. In this study, a simple lithium‐ion doping method is presented and report the dual enhancement effects of lithium ions on CdS and Sb2Se3 layers for the first time. Lithium ions improve the CdS layer by allowing for larger grain sizes, reduces roughness, and increase transmittance in the electron transport layer. At the same time, lightweight Li ions diffuse more easily through the interface into the Sb2Se3 layer, resulting in improved orientation, lower defect density, and a longer carrier lifetime. Furthermore, doping with Li ions changes the band alignment of the CdS/Sb2Se3 junction from a “cliff‐like” to a “spike‐like” configuration, improving carrier transport and reducing carrier recombination near the interface. Ultimately, due to the benefits of Li‐ion doping, the champion device obtained have a VOC of 0.462 V, a JSC of 30.86 mA cm−2, an FF of 65.46%, and an efficiency of 9.33%, representing a 15.8% increase over the undoped device. [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]

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]

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]

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]

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]

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]

Laser-enhanced contact optimisation (LECO) technology can effectively improve the efficiency of tunnel oxide passivated contact (n-TOPCon) solar cells. Generally, the preparation of an emitter in TOPCon cells requires post-oxidation treatment at temperatures exceeding 1030 °C for over 3000 s. This high-temperature post-oxidation process results in reduced surface doping concentration, increased reflectivity of the front of the cell and elevated manufacturing costs of the junction. In this study, through process research, we reveal that the optimal profile depth of emitter (the boron doping concentration at 1 × 1018 atoms/cm3) for mass-produced LECO pastes ranges from 0.44 to 0.52 μm. Additionally, it was discovered that a boron-rich layer (BRL) thinner than 10 nm does not reduce bulk lifetime and increase contact resistivity. Based on these findings, we developed a boron-diffusion method without post-oxidation, which involves controlling the BRL thickness by adjusting the pre-oxidation layer thickness and cycle deposition. When applied to the mass production of n-TOPCon solar cells, this approach resulted in a solar cell conversion efficiency of 26.28 %. This represents an improvement of 0.03 %–0.05 % over traditional boron-diffusion processes. Furthermore, eliminating post-oxidation significantly improved the production capacity and lifespan of the boron-diffusion furnace, thereby reducing the manufacturing costs associated with the solar cells. Furthermore, eliminating post-oxidation significantly improved the production capacity and lifespan of the boron-diffusion furnace, thereby reducing the manufacturing costs associated with the solar cells. • The boron-diffusion method without post-oxidation is proposed. • Mass production of n-TOPCon solar cells with efficiency (26.28 %) is obtained. • The production capacity and lifespan of the boron-diffusion furnace is improved. [ABSTRACT FROM AUTHOR]

For the large-scale development of zinc-air batteries (ZABs), designing efficient, and cost-effective oxygen reduction reaction (ORR) electrocatalysts is crucial yet challenging. Herein, CuFe nanoparticles coupled with Cu–N x active sites co-anchored on 2D nitrogen–doped porous carbon nanosheets (CuFe@Cu–N–C) were obtained by the pyrolysis of Cu–MOF–74, nitrogen source, and ferric salt. The 2D porous carbon structure and the coupling effect between CuFe nanoparticles and Cu–Nx active sites endowed the CuFe@Cu–N–C electrocatalyst with excellent ORR electrocatalytic performance. Consequently, the CuFe@Cu–N–C electrocatalyst exhibited enhanced ORR activity with a higher half–wave potential than Cu–N–C, surpassing even that of the commercial 20 % Pt/C by 21 mV in alkaline media. Additionally, the CuFe@Cu–N–C electrocatalyst exhibited superior ORR stability to commercial 20 % Pt/C. Primary ZABs assembled with the CuFe@Cu–N–C as the cathode ORR electrocatalyst also showed excellent electrochemical properties. The work shows that the prepared CuFe@Cu–N–C electrocatalyst can serve as an ideal alternative to Pt-based catalysts for ZABs. [Display omitted] • A mixed pyrolysis method was proposed to prepare ORR catalyst (CuFe@Cu-N-C). • The CuFe nanoparticles coupled with Cu-N x effectively enhances ORR performance. • The CuFe@Cu-N-C with unique structure increases ORR activity. • The ZAB assembled with CuFe@Cu-N-C exhibits excellent performance. [ABSTRACT FROM AUTHOR]

Perovskite solar cells prepared by inorganic-organic three-dimensional hybrid have good power conversion efficiency, but their operational stability remains a major challenge for commercialization. The defect of perovskite is an important factor restricting its charge dynamics and stability. Here, the rare earth metal chloride CeCl 3 is introduced into perovskite solution to passivate the defects, where the Pb2+ part of the B position is replaced by Ce3+. The prepared films have the characteristics of increasing grain size, enhancing carrier mobility and excellent crystallinity. Meanwhile, via passivating interface defects and improving carrier transport capacity, the generation of non-radiative recombination is reduced, the carrier migration length is extended, and the device performance is improved. The results show that the PCE of the standard device is only 65 % after 2880 h of N 2 atmosphere at room temperature, while the efficiency of the device doped with CeCl 3 can remain at 93 %. When the unencapsulated sample was placed in an air environment (40–60 % humidity), the control sample was reduced to 72 % at 1060 h, while the CeCl 3 was maintained at 87 %. Additionally, the reduction of residual stress in the perovskite layer also provides good bending stability for the flexible target device. These results show that the incorporation of rare earth metal ions is an effective way to stabilize and improve the efficiency of the device. • The Pb2+ part of the B site was replaced by Ce3+ to blunt the defects within the perovskite film. • The perovskite film doped with CeCl 3 exhibited elevated built-in electric field and reduced non-radiation recombination. • After optimization, the PCE of small area device (0.08 cm2) was 23.07 %, while the PCE of large area (22.96 cm2) was 20 %. • After 1060 h storage in the air environment, the PCE of the optimized unpackaged device remained steady at 87 %. [ABSTRACT FROM AUTHOR]

In this study, the EP (epoxy)/L(P) (layered double hydroxides powder)-DTMS (dodecyl-trimethoxy-silane) superhydrophobic composite coating was prepared on AZ31B Magnesium (Mg) alloy surface by spin-coating and self-assembly methods. Mg-Al layered double hydroxides (LDH) powder with ion exchange ability, prepared by hydrothermal coprecipitation, was mixed with EP to construct rough surface and provide good adhesion between the coating and Mg alloy substrate. The introduction of DTMS could reduce the surface energy of coating and improve the compactness of rough surface. Due to the shielding effect of superhydrophobic surface and the ion exchange ability of LDH, it was difficult for corrosive ions (Cl-) to reach the substrate surface in 3.5 wt% NaCl solution. And the corrosion current density was decreased by 4 orders of magnitude. Because of the lubrication of DTMS and the layered structure of L(P), the composite coating had a good wear-reducing effect under the reciprocating point contact mode against with an AISI5200 steel ball. It provided a feasible idea for the construction of multifunctional superhydrophobic coatings on metal surface with self-cleaning, corrosion resistance and wear resistance, which will expand the industrial application fields of superhydrophobic coatings. • EP/L(P)-DTMS composite coating was prepared on Mg alloy surface. • The composite coating was superhydrophobic and had good adhesion. • LDH not only acted as a barrier, but also helped to form micro-nano structure. • The corrosion resistance and wear resistance were greatly improved. [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]

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]

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]

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]

• Screen-printing Ag paste technology plays an important role in n-TOPCon solar cell. • The energy density threshold of UV pulse laser ablate SiN x were investigated. • The mechanism of Al paste and n+-poly-Si contacts was revealed. • The best efficiency was 22.56% with Al paste (25 wt%-29 wt% silicon). Screen-printing Ag paste on the rear side of the Tunnel Oxide Passivated Contact solar cells (TOPCon) is still the mainstream method to form electrodes. However, the high price of precious metals increases the cost of TOPCon cells. Al is a cheap and high-performance conductor, and its work function is compatible with the rear side of TOPCon cells. In this study, we used a UV pulse laser (355 nm, 10 ps) to ablate the rear side SiN x passivation layer of TOPCon cells and then printed Al paste with different weight percentages of silicon (Si-wt.%) on the phosphorus-doped polycrystalline silicon (n+-poly-Si) layer to reduce the cost. We investigated the damage mechanism of laser on SiO x /n+-poly-Si/SiN x passivation structure and the contact mechanism between Al paste and n+-poly-Si layer. The results show that the V oc of SiO x /n+-poly-Si/SiN x passivation structure reduced about 6–7 mV when the laser energy density was 0.431 J/cm2. We got the best electrical performance of TOPCon cells printed with Al paste (25 wt%-29 wt% silicon). The open-circuit voltage (V oc) and the conversion efficiency (E ff), have reached 663.60 mV and 22.56 % respectively. Although the efficiency was 9.40 % relative lower than that of TOPCon cells printed with Ag paste, but the cost of Al paste only accounted for 10 % of Ag paste. In the future, the highest E ff of TOPCon solar cells printed with Al paste on the rear side are expected to reach the commercial TOPCon based on Ag paste, which applies laser doping selective emitter technology (SE) and bifacial poly-Si passivation structure. [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]

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]