Plasmonic Gold Nanostars Incorporated into High-Efficiency Perovskite Solar Cells

Incorporating appropriate plasmonic nanostructures into photovoltaic (PV) systems is of great utility for enhancing photon absorption and thus improving device performance. Herein, the successful integration of plasmonic gold nanostars (AuNSs) into mesoporous TiO2 photoelectrodes for perovskite solar cells (PSCs) is reported. The PSCs fabricated with TiO2-AuNSs photoelectrodes exhibited a device efficiency of up to 17.72 %, whereas the control cells without AuNSs showed a maximum efficiency of 15.19 %. We attribute the origin of increased device performance to enhanced light absorption and suppressed charge recombination

Field emission from single-, double-, and multi-walled carbon nanotubes chemically attached to silicon

The chemical attachment and field emission (FE) properties of single-walled carbon nanotubes (SWCNTs), double-walled carbon nanotubes (DWCNTs), and multi-walled carbon nanotubes (MWCNTs) chemically attached to a silicon substrate have been investigated. A high density of CNTs was revealed by atomic force microscopy imaging with orientation varying with CNT type. Raman spectroscopy was used to confirm the CNT type and diameter on the surfaces. The field emission properties of the surfaces were studied and both current-voltage and Fowler-Nordheim plots were obtained. The SWCNTs exhibited superior FE characteristics with a turn-on voltage (Eto) of 1.28 V μm−1 and electric field enhancement factor (β) of 5587. The DWCNT surface showed an Eto of 1.91 V μm−1 and a β of 4748, whereas the MWCNT surface exhibited an Eto of 2.79 V μm−1 and a β of 3069. The emission stability of each CNT type was investigated and it was found that SWCNTs produced the most stable emission. The differences between the FE characteristics and stability are explained in terms of the CNT diameter, vertical alignment, and crystallinity. The findings suggest that strength of substrate adhesion and CNT crystallinity play a major role in FE stability. Comparisons to other FE studies are made and the potential for device application is discussed

In vivo targeted therapy of gastric tumors via the mechanical rotation of a flower-like Fe3O4@Au nanoprobe under an alternating magnetic field

This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.Owing to their hypotoxicity, great spatial resolution and tomographic properties, Fe3O4 nanoparticles (NPs) are becoming one of the most promising materials for noninvasive biological imaging and shape-dependent therapeutic agents for malignant tumor therapy. Conventional spherical NPs are unable to effectively destroy cellular structure in therapy and thus result in tumors with a high risk of drug resistance. Herein we developed a novel flower-like targeting Fe3O4@Au-HPG-Glc nanoprobe (thiol-containing hyperbranched polyglycerol (HPG); 4-aminophenyl β-D-glucopyranoside (Glc)) that can enhance magnetic resonance imaging (MRI) for cancer therapy. With the guidance of a targeting molecule, Fe3O4@Au-HPG-Glc nanoprobes can precisely target tumor cells. Under an alternating magnetic field (AMF), the flower-like Fe3O4@Au-HPG-Glc nanoprobes can rotate along the central axis of the core to substantially destroy tumor cells by damaging the nucleus or cell membrane. Our results showed that this shape-dependent therapeutic agent-based strategy had remarkable efficacy for MRI-guided tumor therapy. Furthermore, the inhibition of tumor growth in tumor-bearing mice was up to approximately 47.3% on the twelfth day of treatment compared with the level of inhibition in a blank group. Different from other reported methods for cancer therapy, our proposed AMF-dependent targeted cancer therapy is a novel strategy that can potentially reduce drug resistance in gastric tumors

Increased redox-active peptide loading on carbon nanotube electrodes

Carbon nanotube (CNT) electrodes for electrochemistry were fabricated from single- and double-walled carbon nanotubes. The electrodes were subsequently covalently loaded with a ferrocene modified α-aminoisobutyric acid peptide, and the electron transfer (ET) capabilities were probed with cyclic voltammetry. The CNT electrodes comprised of double walled CNTs (DWCNTs) demonstrated significantly higher peak current compared to their single walled counterparts (SWCNTs). This is attributed to a higher loading of the ferrocene modified peptide to the outer wall of the nanotube, through the presence of a larger number of defects sites within the sp2 carbon lattice for the DWCNTs. This higher loading was achieved without compromising the ET rate, indicating that DWCNTs may offer a useful alternative to SWCNTs in future electrochemical sensors and biosensors. © 2012 Elsevier Ltd. All Rights Reserved.Katherine E. Moore, Benjamin S. Flavel, Jingxian Yu, Andrew D. Abell, Joseph G. Shapte

Discontinuous dewetting, template-guided self-assembly, and liquid bridge-transfer printing of high-resolution single-walled carbon nanotube lines for next-generation electrodes and interconnects

A template-guided, self-assembly patterning technique called discontinuous dewetting (DD) and liquid bridge transfer (LBT) was applied to successfully pattern single-walled carbon nanotubes (SWCNTs): the first 1D nanomaterials patterned using the technique. The technique could efficiently and simply pattern SWCNTs with 2.5-10 mu m resolution using little energy, low temperature

Effect of nanotube film thickness on the performance of nanotube-silicon hybrid solar cells

The results of measurements on solar cells made from randomly aligned thin films of single walled carbon nanotubes (SWCNTs) on n-type monocrystalline silicon are presented. The films are made by vacuum filtration from aqueous TritonX-100 suspensions of large diameter arc-discharge SWCNTs. The dependence of the solar cell performance on the thickness of the SWCNT film is shown in detail, as is the variation in performance due to doping of the SWCNT film with SOCl2

Black phosphorus: synthesis and application for solar cells

Few-layer ultrathin nanosheets and ultrasmall quantum dots of black phosphorus (BP) have attracted increasing research interest due to their fascinating properties including a tunable bandgap, high carrier mobility, and ambipolar conduction ability. These excellent properties together with their unique structures make BP derivatives promising candidates for a wide range of device applications. In this research news, the latest advancements in the synthesis, properties, and applications of BP and its derivatives are highlighted. In particular, the focus is on the use of these rising star materials for emerging solar cells, in terms of both theoretical predictions and experimental investigations. Finally, the authors' personal perspectives on potential future research directions are provided