- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Hierarchical NiO@NiS@graphene nanocomposite as a sustainable counter electrode for Pt free dye-sensitized solar cell
摘要： Recent studies in DSSC has been concentrated on developing counter electrode with low cost materials which has high power conversion efficiency, as well as high catalytic property. NiO has been studied as CE for high short circuit current in DSSC because of its wide bandgap. In this work nickel oxide@nickel sulfide@graphene (NiO@NiS@G) nanocomposite was synthesized by hydrothermal method. Structural composition of NiO@NiS@G nanocomposite was revealed by X-ray diffraction (XRD) and confirm the formation of NiO@NiS@G nanocomposites. Raman spectroscopy was the most effective tool for the analysis of carbon-based materials. The D band and G band of Raman spectrum confirmed the conversion of graphene (G) from graphene oxide (GO). X-ray photoelectron spectroscopy (XPS) shows the presence of Ni, O, C and S atoms in the composition. The morphology analysis revealed the formation of NiO@NiS nanoplates anchored on the surface of the graphene sheets. The as-synthesized materials were coated on FTO (fluorine-doped tin oxide) substrate by spray coat technique and their catalytic properties were studied. The electrochemical activity (peak separation Epp) of NiO@NiS@G nanocomposite (391 mV) was high compared to NiO@NiS (496 mV) and exhibited excellent stability compared with NiO@NiS. Further, the charge transfer resistance of commercial Pt, NiO@NiS@G, and Nio@NiS has been measured by Electrochemical Impedance Spectroscopy (EIS), where corresponds resistance values of CEs are 15.7, 23.2, and 36.8 Ω, respectively. The efficiency of a solar cell with NiO@NiS@G is 2.10 % where it high compared with NiO@NiS (1.68%).
关键词： NiO@NiS@G,Counter electrode,Electrochemical activity,graphene,nanoplates
更新于2025-09-16 10:30:52
-
A Dual Role of Amino-functionalized Graphene Quantum Dots in NiOx Films for Efficient Inverted Flexible Perovskite Solar Cells
摘要： NiOx has been widely used as an effective hole transport material for inverted perovskite solar cells (PSCs), particularly flexible PSCs, owing to its low-temperature processing, low cost, and good electron blocking ability. However, the band structure alignment between low-temperature-processed NiOx and the perovskite layer is not satisfactory, resulting in reduced photovoltaic performance. Herein, we report a novel strategy to tune the NiOx hole transport layer for achieving high-performance flexible PSCs. Amino-functionalized graphene quantum dots (AGQDs) are employed in the NiOx film as a dual-role additive. On the one hand, the added AGQDs can provide abundant N atoms at the modified NiOx layer surface to enhance the crystallization of the perovskite film by a Lewis base-acid interaction. On the other hand, the AGQDs can optimize the band structure alignment between the NiOx and perovskite layers, facilitating hole extraction at the NiOx/perovskite interface. As a result, the inverted flexible PSCs exhibit a champion efficiency of 18.10%, which is comparable to the values reported for the current state-of-the-art inverted flexible PSCs. In addition to good air stability, our best flexible device has excellent mechanical stability, retaining 88% of its initial efficiency after continuously bending 1000 times. This new strategy highlights a promising way to enhance the performance of inverted flexible PSCs.
关键词： flexible,amino functionalization,graphene quantum dots,NiO,inverted perovskite solar cells
更新于2025-09-16 10:30:52
-
Novel NiO Nanoforest Architecture for Efficient Inverted Mesoporous Perovskite Solar Cells
摘要： Inverted perovskite solar cells (PSCs) demonstrates attractive features in developing air-stable photovoltaic device, by employing inorganic hole transport layers (HTLs). However, their power conversion efficiencies (PCEs) are still inferior to that of mesoporous n-i-p devices, mainly attributed to the undesirable hole extraction and interfacial recombination loss. Here, we design a novel one-dimensional NiO nanotubes (NTs) nanoforest as efficient mesoporous HTLs. Such NiO NTs mesoporous structure provides the highly conductive pathway for rapid hole extraction, and depresses interfacial recombination loss. Furthermore, excellent light capturing could be achieved by optimizing length and branch growth of NiO NTs nanoforest, which mimics the evolution of natural forest. Therefore, this inverted mesoporous PSCs yields an optimal efficiency of 18.77%, which is still prominent in state-of-the-art NiO-based devices. Alternatively, the mesoporous device exhibits greatly improved long-term stability. This work provides a new design perspective for developing high-performance inverted PSCs.
关键词： mesoporous structure,NiO,hole transporting layer,Inverted perovskite solar cells,nanotube nanoforest
更新于2025-09-12 10:27:22
-
Highly Crystallized C-Doped Nickel Oxide Nanoparticles for p-Type Dye-Sensitized Solar Cells with Record Open-Circuit Voltage Breaking 0.5 V
摘要： In this work, unique carbon-doped NiO nanostructure (denoted as C/NiO) was synthesized via a facile precipitation/reduction reaction, followed by a subsequent oxidation process. The successful introduction of carbon in NiO gave rise to multiple tailing of the physical and electronic characteristics, including morphology, crystallinity, and conductivity, and valence band edge position. The carbon-doped NiO-fabricated dye sensitized solar cells actively generated an unrivalled VOC of 0.50 V and also a significantly increased short-circuit current densities (JSC, 0.202 mA cm-2), leading to an overall efficiency of 0.053%. The improved of photovoltaic performance could be mainly attributed to the significantly enhanced charge transport property and regarded charge recombination occurred at the NiO/electrolyte interface. This work provides an extremely simple and effective strategy for incorporating nonmetal elements in semiconductor oxides with remarkably improved photovoltaic performance.
关键词： charge transport,carbon-doped NiO,dye-sensitized solar cells,photovoltaic performance,valence band edge
更新于2025-09-12 10:27:22
-
Hierarchical heterostructures of nanosheet-assembled NiO-modified ZnO microflowers for high performance acetylene detection
摘要： It is of great signi?cance to monitor internal faults of transformer and ensure its normal and safe operation. Usually, acetylene (C2H2) is considered as the characteristic gas caused by discharge failure in transformer. Using gas sensor technology to analyze dissolved gases in transformer oil is an important strategy. Recently, metal oxide semiconductor (MOS) heterojunctions with tailored microstructures have been developed to fabricate high quality gas sensors for gas detection. In this paper, hierarchical ?ower-like NiO/ZnO heterostructures assembled with 2D nanosheets have been synthesized by a facile hydrothermal method and calcination process. Noticeably, the introduction of di?erent contents of NiO (3.0 at%, 5.0 at% and 10.0 at%) leads to di?erent assembly manners of the building nanosheets into hierarchical ?ower-like structures, thus a?ecting the gas performances. Given this, a variety of microscopic characterization methods were used to observe and compare the di?erences in the structures and morphologies of the composites. Through the gas sensing test, it was found that the 5.0 at% NiO-modi?ed ZnO based sensor exhibited superior sensing performances to C2H2 compared with that of others. The enhanced properties may be attributed to the formation of p-n heterojunctions as well as high porosity of the nanosheets. This promising approach is versatile for the applications of high-quality gas sensors.
关键词： NiO/ZnO composites,Acetylene,Gas sensor,Hierarchical heterostructure
更新于2025-09-12 10:27:22
-
Self-assembled NiO microspheres for efficient inverted mesoscopic perovskite solar cells
摘要： Perovskite solar cells (PSCs) with both normal (n-i-p) and inverted (p-i-n) mesoscopic structures usually exhibit higher e?ciency than their planar counterparts because the mesoporous charge transport layers can supply heterogeneous nucleation sites for growing high quality perovskite crystals and enlarged charge separation area for better charge extraction. However, comparing with the achieved extremely high or even the certi?ed world record e?ciency of mesoscopic PSCs, the signi?cant improvement of inverted mesoscopic PSCs has yet been made, mainly owing to the lack of suitable p-type semiconductors for preparing mesoporous hole transport layers (HTLs). Here, an emulsion-based bottom-up self-assembly strategy is used to prepare NiO microspheres from well-dispersed NiO nanocrystals. The self-assembled NiO microspheres are further used to fabricate mesoporous NiO HTLs of the inverted mesoscopic PSCs. The as-prepared mesoporous NiO HTL with self-assembled NiO microspheres can provide more suitable graded energy alignment, better charge carrier dynamics and reduced dark recombination in the device comparing with the inverted planar PSC with NiO nanocrystal HTL, contributing to obviously enhanced photovoltaic performance and nearly eliminated photocurrent-voltage hysteresis. Due to the general strategy of emulsion-based bottom-up self-assembly for microspheres synthesis, it will overcome the shortage of p-type materials for preparing e?cient inverted mesoscopic PSCs.
关键词： Self-assembled NiO microspheres,Photovoltaic performance,Inverted mesoscopic perovskite solar cell
更新于2025-09-11 14:15:04
-
Long-term stabilized high-density CuBi <sub/>2</sub> O <sub/>4</sub> /NiO heterostructure thin film photocathode grown by pulsed laser deposition
摘要： Harvesting sustainable hydrogen through water-splitting requires a durable photoelectrode to achieve high efficiency and long lifetime. Dense, uniform CuBi2O4/NiO thin film photocathodes grown by pulsed laser deposition achieved photocurrent density over 1.5 mA cm-2 at 0.4 VRHE and long-term chronoamperometric stability for over 8 hours.
关键词： heterostructure,pulsed laser deposition,water-splitting,CuBi2O4,NiO,hydrogen,photocathode
更新于2025-09-11 14:15:04
-
Coupling heterostructure of thickness-controlled nickel oxide nanosheets layer and titanium dioxide nanorod arrays via immersion route for self-powered solid-state ultraviolet photosensor applications
摘要： A coupling heterostructure consisting of nickel oxide nanosheets (NNS) and titanium dioxide nanorod arrays (TNAs) was fabricated for self-powered solid-state ultraviolet (UV) photosensor applications. By controlling the thickness of the NNS layer by via varying the growth time from 1 to 5 h at a deposition temperature of 90 °C, the coupling NNS/TNAs heterojunction films were formed and their structural, optical, electrical and UV photoresponse properties were investigated. The photocurrent measured from the fabricated self-powered UV photosensor was improved by increasing the thickness of NNS from 140 to 170 nm under UV irradiation (365 nm, 750 mWcm?2) at 0 V bias. A maximum photocurrent density of 0.510 mA?cm?2 was achieved for a sample with a NNS thickness of 170 nm and prepared with a 3 h NNS growth time. Our results showed that the fabricated NNS/TNAs heterojunction has potential applications for self-powered UV photosensors.
关键词： TiO2 nanorods,Electronic materials,Semiconductors,Immersion route,Photosensor,NiO nanosheets
更新于2025-09-11 14:15:04
-
Fabrication of ZnO/NiO transparent solar cells by electrochemical deposition
摘要： In this study, ZnO/NiO solar cells are fabricated by electrochemical deposition for the first time. Ni(OH)2 precursor films are deposited in an aqueous solution containing Ni(NO3)2 with a current density high enough for water electrolysis to occur. The Ni(OH)2 films are then converted to NiO films by annealing them in 400oC air. ZnO is deposited on the NiO layer from a solution containing Zn(NO3)2. The best-performing cell has an open-circuit voltage of 41 mV and a short-circuit current of 4.2 μA/cm2.
关键词： solar cell,NiO,ZnO,heterostructure,electrochemical deposition
更新于2025-09-11 14:15:04
-
Active {1?1?1}-faceted ultra-thin NiO single-crystalline porous nanosheets supported highly dispersed Pt nanoparticles for synergetic enhancement of gas sensing and photocatalytic performance
摘要： Proper morphology, surface and interface structure designing are required to obtain e?cient gas sensing and photocatalytic materials. In the present work, ultra-thin NiO single-crystalline porous nanosheets with dominant {1 1 1} crystal facets (denoted as SP-NiO) and hierarchical NiO porous microspheres (denoted as HP-NiO) supported highly dispersed Pt nanoparticles with controllable sizes were designed and synthesized. Their gas sensing and photocatalytic performance were investigated. It was found that both the formaldehyde sensing and methyl orange photocatalytic degradation performance were greatly enhanced by decorating Pt nanoparticles on SP-NiO, while Pt nanoparticles decoration contributed little to the improved photocatalytic performance of HP-NiO. The results indicated that surface structure of the NiO support could also produce signi?cant impact on the activity of Pt/NiO heterojunctions. Moreover, Pt decorated SP-NiO with stable structure showed a marked long-term stability with negligible attenuation of gas sensitivity (less than 5%) for 45 days, while Pt decorated HP-NiO exhibited obvious attenuation of gas sensitivity (more than 30%) due to the structural collapse. The work not only o?ers promising materials for gas sensing and photocatalytic application, but also brings new dawn for the designing of e?cient p-type metal oxides gas sensing and photocatalytic materials through the synergistic e?ect of single-crystalline porous structures modulation, crystal facets engineering and facet-selective deposition of highly-dispersed Pt nanoparticles.
关键词： Photocatalysis,Ultra-thin,{1 1 1} crystal facets,NiO,Gas sensing
更新于2025-09-10 09:29:36