- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Enhanced device performance with passivation of the TiO <sub/>2</sub> surface using a carboxylic acid fullerene monolayer for a SnPb perovskite solar cell with a normal planar structure.
摘要： Research on tin-lead (SnPb) perovskite solar cells (PSCs) have gained popularity in recent years due to their low bandgap which could be applied to tandem solar cells. However, most of the work are based on inverted PSCs using PEDOT:PSS as the hole transport layer as the normal structure PSCs show lower efficiency. In this work, the reason behind the low efficiency of normal structure SnPb PSCs is elucidated and the method to overcome the problem has been attempted through surface passivation. In the case of normal PSCs, at the interface between titania layer and SnPb perovskite there are many carrier traps observed originating from Ti-O-Sn bonds. In order to avoid the direct contact between titania and SnPb perovskite layer, the titania surface is passivated with carboxylic acid C60 resulting in efficiency increase from 5.14 % to 7.91 %. This will provide a direction of enhancing the efficiency of normal structure SnPb PSCs through heterojunction engineering.
关键词： passivation,Perovskite solar cells,Tin,titania,Lead,trap density,interface
更新于2025-09-23 15:19:57
-
An effective strategy to boost 3D perovskite light-emitting diode performance via solvent mixing strategy
摘要： In this study, we demonstrate a simple method to achieve highly efficient perovskite light-emitting diode (PeLED) via casting the neat methylammonium bromide (MABr) in mixed solvents with different solubility on top of the perovskite layer for bulk recrystallization and interfacial passivation. The perovskite crystals reacting with MABr can be reformed orderly and stereoscopically with a reduced domain size on surface and reduced grain boundaries in bulk, which is advantageous to obtain strong fluorescence intensity and long exciton lifetime. The remaining MABr molecule that does not react with perovskite can attach on the recrystallized perovskite surface to develop a passivation layer, which can effectively eliminate exciton interface recombination in PeLEDs. The optimized PeLED exhibits a maximum luminance of 27692.2 cd m-2, which is more than 11 times and 2 times higher than the control device without MABr treatment and the control device with high MABr molar ratio and thin perovskite film thickness, respectively. This work provides an effective strategy to boost PeLED performance by optimizing mixed solvent ratios and concentrations of organic ligand MABr without changing the thickness of the emitting layer.
关键词： charge balance,morphological manipulation,passivation,perovskite light-emitting diode,recrystallization
更新于2025-09-23 15:19:57
-
Correlated alkyl chain length to defect passivation efficacy in perovskite solar cells
摘要： We for the first time correlated the alkyl chain length of amine molecules to the defect passivation efficacy, either on surface or at grain boundaries of perovskite films. Blade-coated perovskite solar cells with long-chain amines passivation achieved an efficiency of 21.5%, accompanied by a small voltage loss of 0.35 V.
关键词： efficiency,defect passivation,blade-coating,alkyl chain length,perovskite solar cells
更新于2025-09-23 15:19:57
-
A Novel 2D Perovskite as Surface a??Patchesa?? for Efficient Flexible Perovskite Solar Cells
摘要： Two-dimensional (2D) perovskites are promising passivating materials to improve the photovoltaic performance and stability of lead halide perovskite solar cells (PSCs). In this work, we report a novel mixed 2D perovskite based on phenylformamidinium (PFA) cations and formamidinium (FA) cations as surface “patches” to stabilize an FA-based perovskite, whose formula is Cs0.05Rb0.05(FA0.83MA0.17)Pb(I0.95Br0.05)3. The mixed-cation 2D perovskite “patches” can be obtained by dripping a PFA iodide (PFAI) solution (≥ 6 mg/mL) dynamically on the FA-based perovskite film surface. The mixed-cation 2D perovskite can effectively reduce the perovskite surface defects and suppress the recombination at the interface between the perovskite layer and the hole transport layer, which results in improved device performance and thermal stability. Our champion flexible PSC presents a power conversion efficiency (PCE) of 19.89%, which is one of the highest reported values for single-junction flexible PSCs to date. The unencapsulated flexible device with the “patches” retains 70.4% of its initial efficiency after 1000 h at 85 °C in an N2 environment. Our new strategy demonstrates a highly promising way to passivate the FA-based perovskite surface for highly-efficient PSCs, particularly flexible PSCs.
关键词： 2D perovskite,grain boundary,passivation,flexible,perovskite solar cells
更新于2025-09-23 15:19:57
-
Investigation of interface characteristics of Al2O3/Si under various O2 plasma exposure times during the deposition of Al2O3 by PA-ALD
摘要： Plasma-assisted atomic layer deposition (PA-ALD) is more suitable than thermal atomic layer deposition (ALD) for mass production because of its faster growth rate. However, controlling surface damage caused by plasma during the PA-ALD process is a key issue. In this study, the passivation characteristics of Al2O3 layers deposited by PA-ALD were investigated with various O2 plasma exposure times. The growth per cycle (GPC) during Al2O3 deposition was saturated at approximately 1.4 ?/cycle after an O2 plasma exposure time of 1.5 s, and a refractive index of Al2O3 in the range of 1.65–1.67 was obtained. As the O2 plasma exposure time increased in the Al2O3 deposition process, the passivation properties tended to deteriorate, and as the radio frequency (RF) power increased, the passivation uniformity and the thermal stability of the Al2O3 layer deteriorated. To study the Al2O3/Si interface characteristics, the capacitance-voltage (C-V) and the conductance-voltage (G-V) were measured using a mercury probe, and the ?xed charge density (Qf) and the interface trap density (Dit) were then extracted. The Qf of the Al2O3 layer deposited on a Si wafer by PA-ALD was almost una?ected, but the Dit increased with O2 plasma exposure time. In conclusion, as the O2 plasma exposure time increased during Al2O3 layer deposition by PA-ALD, the Al2O3/Si interface characteristics deteriorated because of plasma surface damage.
关键词： Plasma-assisted atomic layer deposition,Plasma damage,Silicon solar cell,Passivation,Al2O3
更新于2025-09-23 15:19:57
-
Enhancing photocatalytic activity of tantalum nitride by rational suppression of bulk, interface and surface charge recombination
摘要： Rational design of photocatalysts is essential to achieve efficient solar energy conversion. For narrow bandgap Ta3N5 photocatalyst, various charge recombination occurring in the bulk, interface and on the surface significantly impairs its activity for solar hydrogen (H2) generation. Herein, a synergistic engineering approach is designed to solve this critical recombination challenge. First, hollow spherical structure of Ta3N5 with Mg doping is prepared to not only reduce the charge migration distance and increase the surface area, but also increase the electron mobility for facilitated charge transfer. Second, an MgO nano-layer covers the surface of hollow Ta3N5 structure to passivate surface defects, thus promoting the interfacial charge transfer between Ta3N5 and co-catalysts. Finally, dual co-catalysts (Pt/CoOx) for redox reactions are loaded onto the hollow Ta3N5 structure to reduce the surface recombination and overcome the sluggish surface reaction. Remarkably, the combination of hollow structure, Mg2+ doping, MgO interfacial layer, and dual co-catalysts effectively improves the charge separation and transfer in Ta3N5 photocatalyst. This newly designed photocatalyst exhibits a considerably improved H2 generation performance of 56.3 μmol h-1 under simulated sunlight, compared to that of reference Pt/Ta3N5 hollow spheres.
关键词： doping,hollow structure,co-catalyst,surface passivation,tantalum nitride
更新于2025-09-19 17:15:36
-
Remote plasma-enhanced atomic layer deposition of gallium oxide thin films with NH <sub/>3</sub> plasma pretreatment
摘要： High quality gallium oxide (Ga2O3) thin films are deposited by remote plasma-enhanced atomic layer deposition (RPEALD) with trimethylgallium (TMG) and oxygen plasma as precursors. By introducing in-situ NH3 plasma pretreatment on the substrates, the deposition rate of Ga2O3 films on Si and GaN are remarkably enhanced, reached to 0.53 and 0.46 ?/cycle at 250 °C, respectively. The increasing of deposition rate is attributed to more hydroxyls (–OH) generated on the substrate surfaces after NH3 pretreatment, which has no effect on the stoichiometry and surface morphology of the oxide films, but only modifies the surface states of substrates by enhancing reactive site density. Ga2O3 film deposited on GaN wafer is crystallized at 250 °C, with an epitaxial interface between Ga2O3 and GaN clearly observed. This is potentially very important for reducing the interface state density through high quality passivation.
关键词： RPEALD,NH3 plasma,Ga-oxide,passivation
更新于2025-09-19 17:15:36
-
Surface passivation and point-defect control in Cu(In,Ga)Se <sub/>2</sub> films with a Na <sub/>2</sub> S post deposition treatment for higher than 19% CIGS cell performance
摘要： Na2S as a new alkaline source was employed to passivate the surface of CIGS film. Na2S has less formation enthalpy compared to alkali fluoride compounds leading to the more effective dissolution at the surface. An efficiency of 19.2% was obtained by post deposition treatment (PDT) with Na2S source for cell with anti-reflective coating and active area of a 0.43cm2. The remarkable performance enhancement compared to the efficiency of 16.64% of the cell without the PDT was due to the increase of Voc and FF. With the Na2S PDT, Na distribution in CIGS film was much shallower and the valence band lowering was smaller compared to that with NaF PDT. The emission intensity of low-temperature photoluminescence at 1.04 eV, which corresponds to electron transition from In-in-Cu (InCu) antisite to the valence band maximum, was greatly reduced by Na2S PDT compared to NaF PDT. The result suggests that in addition to lowering the Cu vacancy concentration, the concentration of InCu defects significantly decreased at the CIGS surface by Na2S PDT compared to NaF PDT. Our results indicated that the surface passivation by Na2S PDT was more effective than NaF PDT.
关键词： point defects,Na2S source,CIGS solar cells,surface passivation,post-deposition treatment (PDT)
更新于2025-09-19 17:15:36
-
Wafer-scale HfO<sub>2</sub> encapsulated silicon nanowire field effect transistor for efficient label-free DNA hybridization detection in dry environment
摘要： Silicon nanowire (SiNW) charge based biosensors are attractive for DNA sensing applications due to their compactness and large surface-to-volume ratio. Small feature size, low production cost, repeatability, high sensitivity and selectivity are some of the key requirements for biosensors. The most common e-beam manufacturing method employed to manufacture sub-nm SiNWs is both cost and time intensive. Therefore, we propose a highly reproducible CMOS industry grade low-cost process to fabricate SiNW based field effect transistors on 4”-wafers. The 60 nm wide SiNWs reported in this paper are fabricated using the sidewall transfer lithography process which is a self-aligned-double-patterning I-line lithography process that also facilitates encapsulation of the SiNW surface with a thin HfO2 layer on which DNA probes are grafted to finalize the biosensors. Upon DNA hybridization, SiNW devices exhibit threshold voltage shift larger than the noise introduced by the exposition to saline solutions used for the bioprocesses. More specifically, based on a statistical analysis, we demonstrate that 85% of the tested devices exhibit a positive threshold voltage shift after DNA hybridization. These promising results make way for the monolithic integration of SiNW biosensors and CMOS circuitry to realize a point of care device which can offer reliable real time electrical readout.
关键词： HfO2 passivation,silicon nanowire hybridization,silicon nanowire,DNA sensing,pattern transfer lithography,biosensor
更新于2025-09-19 17:15:36
-
Delocalized molecule surface electronic modification for enhanced performance and high environmental stability of CsPbI2Br perovskite solar cells
摘要： All-inorganic perovskites have drawn tremendous attentions in view of their superb thermal stability. However, unavoidable defects near the perovskite surface seriously hampers carrier transport and easily results in ion accumulation at the interface of perovskite layer and charge transport layer. Herein, delocalized thiazole and imidazole derivatives iodide salts functionalized on perovskite surface have been investigated comprehensively. These two salts post-treatment on perovskite could efficiently passivate traps arising from Cs+ or I- vacancies. Additionally, these highly п-conjugated delocalized molecules can contribute to the efficient charge transport and prevent ions accumulation at the interface. As a result, sulfur-contained aminothiazolium iodide (ATI) post-treated CsPbI2Br devices showed simultaneous enhanced current density and voltage due to its higher interaction with perovskite lattice, this led to a champion efficiency of 13.91% with superb fill factor of more than 80%, which exhibited dramatic enhancement compared with the control samples (10.12%). Furthermore, surface passivation with delocalized molecules could effectively stabilize CsPbI2Br phase at room temperature or 80 °C annealing in ambient condition (65% RH). Equally important, this surface passivation allowed competitive efficiency of 11.26% with a large-area device (1.00 cm2). This high kill tolerant approach provide a new route to fabricate inorganic perovskite devices with higher efficiency and stability.
关键词： rapid charge transfer,surface passivation,all-inorganic perovskite,delocalized molecules,higher performance
更新于2025-09-19 17:13:59