- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Subtle Molecular Tailoring Induces Significant Morphology Optimization Enabling over 16% Efficiency Organic Solar Cells with Efficient Charge Generation
摘要： Manipulating charge generation in a broad spectral region has proved to be crucial for nonfullerene-electron-acceptor-based organic solar cells (OSCs). 16.64% high efficiency binary OSCs are achieved through the use of a novel electron acceptor AQx-2 with quinoxaline-containing fused core and PBDB-TF as donor. The significant increase in photovoltaic performance of AQx-2 based devices is obtained merely by a subtle tailoring in molecular structure of its analogue AQx-1. Combining the detailed morphology and transient absorption spectroscopy analyses, a good structure–morphology–property relationship is established. The stronger π–π interaction results in efficient electron hopping and balanced electron and hole mobilities attributed to good charge transport. Moreover, the reduced phase separation morphology of AQx-2-based bulk heterojunction blend boosts hole transfer and suppresses geminate recombination. Such success in molecule design and precise morphology optimization may lead to next-generation high-performance OSCs.
关键词： solar cell morphology,organic solar cells,power conversion efficiency,nonfullerene acceptors,charge generation
更新于2025-09-12 10:27:22
-
A Study of Structure and Morphology of Bulk Metallic Glasses after Laser Beam Treatment
摘要： Recently, the Zr-based bulk metallic glasses (BMGs) have attracted attention because of their good glass-forming ability and excellent mechanical properties. The amorphous structure is thermodynamically unstable, and it tends to change into an equilibrium crystalline state. The objective of this work is to test the influence of the laser beam on the surface structure and morphology of BMGs with zirconium matrix. The material for the examination was Zr55Cu30Ni5Al10 alloy obtained by high-pressure copper mold casting method in the form of a plate in specified dimensions. In this paper, irradiation with single impulse and laser beam welding emitted in a pulsed mode which consists of a series of overlapping point interactions were used. Different parameters of the laser beam were employed. Microscopic observations proved that after laser treatment amorphous-crystalline structure appears in the heat-affected zone (HAZ). High-resolution transmission electron microscopy analysis of irradiated metallic glass showed that small amount of crystalline Zr2Ni-type phase was produced in the HAZ, whereas in the fusion zone and parent material amorphous structure appears. What is more, it has been observed that the higher laser beam frequency and energy the more weld penetration takes the shape of an ellipse.
关键词： Zr-based alloy,bulk metallic glasses,laser melting,surface morphology
更新于2025-09-12 10:27:22
-
Role of surfactant in optimization of 3D ZnO floret as photoanode for dye sensitized solar cell
摘要： We demonstrate structural, optical and morphological characteristics of surfactant stabilized ZnO floret array by X-ray diffractometer (XRD), Photoluminescence spectrometer, field emission scanning electron microscope (FESEM), and high resolution transmission electron microscope (HRTEM). Effects of using weak and strong bases as hexamethylenetetraamine and ammonium hydroxide which work as surfactant have been investigated. High crystallinity has been indicated by XRD patterns. The HRTEM and FESEM reveal that synthesized samples are composed of nanopetal assembled in a shape of floret array. The proposed growth mechanism of 3D ZnO floret arrays exhibits that tremendous amount of ZnO kernel clumps with each other and appears as a broad root for the growing of floret array-like structure. ZnO floret array as photoanode material was used in dye sensitized solar cell (DSSC). This distinctive morphology significantly increases the photovoltaic parameters of DSSC. The optimized efficiency for ZnO floret array as photoanode was found to be 6.6%.
关键词： Metal oxide semiconductor,Microstructure,Morphology variation
更新于2025-09-12 10:27:22
-
Effect of fractal parameters on optical properties of cold rolled aluminum alloy strips with induced surface deflection: simulations and experimental correlations
摘要： Cold rollings for Al5182 aluminum alloy strips are carried out to evaluate the optical parameters with the applications of two lubricants and various operating conditions. In order to obtain these optical parameters, the fractal parameters which includes periodic lengths (????, ????) and fractal dimensions (????, ????) in the modified three-dimensional formula for the fractal surface between two predominant asperities and increase minimum illuminance and decrease maximum provide an effective way to correlate these fractal parameters with the optical parameters using TracePro software, which can help to define rolling conditions efficiently for the specific demand morphology have been solved first for the rolled surfaces. This three-dimensional formula can minimum illuminance. While an increment in ???? and ???? would increase the characteristic distance of optical properties. The deterministic results for fractal surface simulations using MATLAB in series and 20o incident angle simulation in TracePro software explain that an increase in ???? and ???? will yield dense profiles which elevates the maximum illuminance and lower down the illuminance. Finite element analyses prove that different friction coefficients in the upper and lower rolls potentially induce surface deflection and thus affect the optical properties. A high illuminance uniformity can be achieved by making a compromise among the fractal parameters (????, ????, ???? and ????) such that a small difference in the maximum and minimum illuminances is available.
关键词： Induced deflection angle after rolling,3D formula for fractal surface morphology,Optical properties in reflection,Fractal dimensions and periodic lengths of rolled surface
更新于2025-09-12 10:27:22
-
13.34% Efficiency Nonfullerene All-Small-Molecule Organic Solar Cells Enabled by Modulating Crystallinity of Donors via a Fluorination Strategy
摘要： Nonfullerene all-small-molecule organic solar cells (NFSM-OSCs) have shown a promising potential towards the commercialization of OSCs, owing to their unique advantages of high purity, easy synthesis and good reproducibility. However, great challenges in the modulation of phase separation morphology have limited their future development. Herein, two novel small molecular donors of BTEC-1F and BTEC-2F, derived from the small molecule DCAO3TBDTT, were designed and synthesized. While using Y6 as the acceptor, the devices based on non-fluorinated DCAO3TBDTT showed an open circuit voltage (Voc) of 0.804 V and a power conversion efficiency (PCE) of 10.64%. Mono-fluorinated BTEC-1F showed an increased Voc of 0.870 V and a PCE of 11.33%. More impressively, the fill factor (FF) of di-fluorinated BTEC-2F based NFSM-OSC was largely improved to 72.35% resulting in an impressive PCE of 13.34%, which was much higher than that of BTEC-1F (61.35%) and DCAO3TBDTT (60.95%). To the best of our knowledge, this is the highest reported PCE to date for NFSM-OSCs. BTEC-2F depicted a more compact molecular stacking and a lower crystallinity as revealed from characterization studies, which was beneficial for enhancing phase separation and carrier transport. Those results demonstrated an effective strategy to improve the performance of NFSM-OSCs via fluorination of small molecular donors and modulation of crystallinity deviation between donors and acceptors.
关键词： morphology,all-small-molecule organic solar cells,crystallinity,fluorination,orientation modulation
更新于2025-09-12 10:27:22
-
13.7% Efficiency Small‐Molecule Solar Cells Enabled by a Combination of Material and Morphology Optimization
摘要： Compared with the quick development of polymer solar cells, achieving high-efficiency small-molecule solar cells (SMSCs) remains highly challenging, as they are limited by the lack of matched materials and morphology control to a great extent. Herein, two small molecules, BSFTR and Y6, which possess broad as well as matched absorption and energy levels, are applied in SMSCs. Morphology optimization with sequential solvent vapor and thermal annealing makes their blend films show proper crystallinity, balanced and high mobilities, and favorable phase separation, which is conducive for exciton dissociation, charge transport, and extraction. These contribute to a remarkable power conversion efficiency up to 13.69% with an open-circuit voltage of 0.85 V, a high short-circuit current of 23.16 mA cm?2 and a fill factor of 69.66%, which is the highest value among binary SMSCs ever reported. This result indicates that a combination of materials with matched photoelectric properties and subtle morphology control is the inevitable route to high-performance SMSCs.
关键词： morphology,energy loss,power conversion efficiency,small-molecule solar cells,nonfullerene acceptors
更新于2025-09-12 10:27:22
-
13.34% Efficiency Nonfullerene All‐Small‐Molecule Organic Solar Cells Enabled by Modulating Crystallinity of Donors via a Fluorination Strategy
摘要： Nonfullerene all-small-molecule organic solar cells (NFSM-OSCs) have shown a promising potential towards the commercialization of OSCs, owing to their unique advantages of high purity, easy synthesis and good reproducibility. However, great challenges in the modulation of phase separation morphology have limited their future development. Herein, two novel small molecular donors of BTEC-1F and BTEC-2F, derived from the small molecule DCAO3TBDTT, were designed and synthesized. While using Y6 as the acceptor, the devices based on non-fluorinated DCAO3TBDTT showed an open circuit voltage (Voc) of 0.804 V and a power conversion efficiency (PCE) of 10.64%. Mono-fluorinated BTEC-1F showed an increased Voc of 0.870 V and a PCE of 11.33%. More impressively, the fill factor (FF) of di-fluorinated BTEC-2F based NFSM-OSC was largely improved to 72.35% resulting in an impressive PCE of 13.34%, which was much higher than that of BTEC-1F (61.35%) and DCAO3TBDTT (60.95%). To the best of our knowledge, this is the highest reported PCE to date for NFSM-OSCs. BTEC-2F depicted a more compact molecular stacking and a lower crystallinity as revealed from characterization studies, which was beneficial for enhancing phase separation and carrier transport. Those results demonstrated an effective strategy to improve the performance of NFSM-OSCs via fluorination of small molecular donors and modulation of crystallinity deviation between donors and acceptors.
关键词： morphology,all-small-molecule organic solar cells,crystallinity,fluorination,orientation modulation
更新于2025-09-12 10:27:22
-
Evolution of surface morphology of Er:YAG laser-machined human bone
摘要： The extensive research on the laser machining of the bone has been, so far, restricted to drilling and cutting that is one- and two-dimensional machining, respectively. In addition, the surface morphology of the laser machined region has rarely been explored in detail. In view of this, the current work employed three-dimensional laser machining of human bone and reports the distinct surface morphology produced within a laser machined region of human bone. Three-dimensional laser machining was carried out using multiple partially overlapped pulses and laser tracks with a separation of 0.3 mm between the centers of consecutive laser tracks to remove a bulk volume of the bone. In this study, a diode-pumped pulse Er:YAG laser (λ = 2940 nm) was employed with continuously sprayed chilled water at the irradiation site. The resulting surface morphology evolved within the laser-machined region of the bone was evaluated using scanning electron microscopy, energy dispersive spectroscopy, and X-ray micro-computed tomography. The distinct surface morphology involved cellular/channeled scaffold structure characterized by interconnected pores surrounded by solid ridges, produced within a laser machined region of human structural bone. Underlying physical phenomena responsible for evolution of such morphology have been proposed and explained with the help of a thermokinetic model.
关键词： Laser osteotomy,Laser machining,Surface morphology,Er:YAG laser,Scaffold
更新于2025-09-12 10:27:22
-
Regulation of Molecular Packing and Blend Morphology by Finely Tuning Molecular Conformation for High-Performance Nonfullerene Polymer Solar Cells
摘要： The asymmetric thienobenzodithiophene (TBD) structure is first systematically compared with the benzo[1,2-b:4,5-b′]dithiophene (BDT) and dithieno[2,3-d:2′,3′-d′]benzo[1,2-b:4,5-b′]dithiophene (DTBDT) units in donor-acceptor (D-A) copolymers and applied as the central core in small molecule acceptors (SMAs). Specific polymers including PBDT-BZ, PTBD-BZ, and PDTBDT-BZ with different macromolecular conformations are synthesized and then matched with four elaborately designed acceptor-donor-acceptor (A-D-A) SMAs with structures comparable to their donor counterparts. The resulting polymer solar cell (PSC) performance trends are dramatically different from each other and highly material-dependent, and the active layer morphology is largely governed by the polymer conformation. Due to its more linear backbone, the PTBD-BZ film has higher crystallinity and more ordered and denser π–π stacking than those of the PBDT-BZ and PDTBDT-BZ films. Thus, PTBD-BZ shows excellent compatibility with and strong independence on the SMAs with varied structures, and PTBD-BZ-based cells deliver high power conversion efficiency (PCE) of 10~12.5%, whereas low PCE is obtained by cells based on PDTBDT-BZ due to its zigzag conformation. Overall, this study reveals control of molecular conformation as a useful approach to modulate the photovoltaic (PV) properties of conjugated polymers.
关键词： morphology,nonfullerene solar cell,power conversion efficiency,asymmetrical backbone,molecular conformation
更新于2025-09-12 10:27:22
-
Solution of maximum laser ablation depth based on dynamic energy distribution model
摘要： Pulsed laser ablation (PLA) is widely applied in mechanical processing with its energy distribution determining the quantity of removed material. Thus, the accurate description of energy distribution accumulated on component surface is crucial for further study of ablation morphology, such as the maximum ablation depth in laser patterning. However, there exist the overlapping area between adjacent laser spots and the non-continuity of laser energy here, which increase the inaccuracy of energy distribution description proverbially. By comprehensively considering the discrete distribution for laser spots and the non-uniform features for energy distribution, the innovative approach is proposed to establish a feasible dynamic energy distribution model in PLA quantitatively, with an idea of continuous approximation to resolve its discrete characteristic. More significantly, based on the proposed model, a new method is also presented to tackle PLA morphology prediction, just the maximum laser ablation depth in laser patterning. Finally, FEA simulations and experiments are performed to investigate the proposed model and method which endorse the robust and efficient theoretical model for reliable yet fast calculation of the maximum ablation depth.
关键词： distribution,depth,copper,morphology,ablation,frequency,energy,model,velocity,Laser
更新于2025-09-12 10:27:22