Miniaturized spectrometer based on MLP neural networks and a frosted glass encoder.

Computational spectrometers are explored to overcome the disadvantages of large size, narrow bandwidth and low spectral resolution suffered by conventional spectrometers. However, expensive spectral encoders and unstable algorithms impede widespread applications of the computational spectrometers. In this paper, we propose a neural network (NN)-based miniaturized spectrometer with a frosted glass as its spectral encoder.

Enhancing the Performance of Perovskite Solar Cells by Introducing 4-(Trifluoromethyl)-1-imidazole Passivation Agents.

Defects in perovskite films are one of the main factors that affect the efficiency and stability of halide perovskite solar cells (PSCs). Uncoordinated ions (such as Pb, I) act as trap states, causing the undesirable non-radiative recombination of photogenerated carriers. The formation of Lewis acid-base adducts in perovskite directly involves the crystallization process, which can effectively passivate defects.

Highly Efficient Perovskite Solar Cell Based on PVK Hole Transport Layer.

A π-conjugated small molecule N, N'-bis(naphthalen-1-yl)-N, N'-bis(phenyl)benzidine (NPB) was introduced into poly(9-vinylcarbazole) (PVK) as a hole transport layer (HTL) in inverted perovskite solar cells (PSCs). The NPB doping induces a better perovskite crystal growth, resulting in perovskite with a larger grain size and less defect density. Thus, the V, J and FF of the PSC were all enhanced.

Defect Passivation Using Trichloromelamine for Highly Efficient and Stable Perovskite Solar Cells.

Nonradiative recombination losses caused by defects in the perovskite layer seriously affects the efficiency and stability of perovskite solar cells (PSCs). Hence, defect passivation is an effective way to improve the performance of PSCs. In this work, trichloromelamine (TCM) was used as a defects passivator by adding it into the perovskite precursor solution.

Mechanism study on highly efficient polymer light-emitting diodes utilizing double-layered alkali halide electron injection layer.

Enhancing the injection of electron is an effective strategy to improve the performance of polymer light-emitting diodes (PLEDs). In this work, we reported a 286% improvement in current efficiency (CE) of PLEDs by using double-layered alkali halide electron injection layer (EIL) NaCl/LiF instead of LiF. A significant enhancement of electron injection was observed after inserting the NaCl layer.

Morphology control of organic halide perovskites by adding BiFeO nanostructures for efficient solar cell.

The morphology of perovskite light-absorption layer plays an important role in the performance of perovskite solar cells (PSCs). In this work, BiFeO (BFO) nanostructures were used as additive for CHNHPbI (MAPbI) via anti-solvent method. The addition of BFO nanostructures greatly enhanced the crystallinity, grain size and film uniformity of MAPbI.

Oral microbiota and gastrointestinal cancer.

The microbiota inhabiting the oral cavity is a complex ecosystem and responsible for resisting pathogens, maintaining homeostasis, and modulating the immune system. Some components of the oral microbiota contribute to the etiology of some oral diseases. Accumulating evidence suggests that the human oral microbiota is implicated in the development and progression of gastrointestinal cancer.

Improving the Performances of Perovskite Solar Cells via Modification of Electron Transport Layer.

The commonly used electron transport material (6,6)-phenyl-C61 butyric acid methyl ester (PCBM) for perovskite solar cells (PSC) with inverted planar structures suffers from properties such as poor film-forming. In this manuscript, we demonstrate a simple method to improve the film-forming properties of PCBM by doping PCBM with poly(9,9-dioctylfluorene-co-benzothiadiazole) (F8BT) as the electron transport layer (ETL), which effectively enhances the performance of CH₃NH₃PbI₃ based solar cells. With 5 wt % F8BT in PCBM, the short circuit current (J) and fill factor (FF) of PSC both significantly increased from 17.

Understanding the Effect of Delay Time of Solvent Washing on the Performances of Perovskite Solar Cells.

Uniform and dense perovskite films were realized by the one-step solution-processing method combined with toluene washing. The influence of the delay time applied for toluene washing on the film quality of CHNHPbI (MAPbI) was investigated in a comprehensive manner. The optimal delay time was experimentally observed at the critical point when the color of the film changes from transparent to hazy.

Highly Promoting the Performances of Polymer Light-Emitting Diodes via Control of the Residue of a Polar Solvent on an Emissive Layer.

The polar solvent dimethylformamide (DMF) was used to treat the emissive layer (EML) of polymer light-emitting diodes (PLEDs). The formation of a dipole layer at the EML/cathode interface after DMF treatment was proven, which led to a reduction of the electron-injection barrier. The dipole layer was formed mainly because of the intrinsic polarity of DMF.

Morphology Analysis and Optimization: Crucial Factor Determining the Performance of Perovskite Solar Cells.

This review presents an overall discussion on the morphology analysis and optimization for perovskite (PVSK) solar cells. Surface morphology and energy alignment have been proven to play a dominant role in determining the device performance. The effect of the key parameters such as solution condition and preparation atmosphere on the crystallization of PVSK, the characterization of surface morphology and interface distribution in the perovskite layer is discussed in detail.

Significant Lowering Optical Loss of Electrodes via using Conjugated Polyelectrolytes Interlayer for Organic Laser in Electrically Driven Device Configuration.

One of the challenges toward electrically driven organic lasers is the huge optical loss associated with the contact of electrodes and organic gain medium in device. We demonstrated a significant reduction of the optical loss by using our newly developed conjugated polyelectrolytes (CPE) PPFN(+)Br(-) as interlayer between gain medium and electrode. The optically pumped amplified spontaneous emission (ASE) was observed at very low threshold for PFO as optical gain medium and up to 37 nm thick CPE as interlayer in device configuration, c.

Fabrication of high-quality graphene oxide nanoscrolls and application in supercapacitor.

We reported a simple and effective way of fabricating one-dimensional (1D) graphene oxide nanoscrolls (GONS) from graphene oxide (GO) sheets through shock cooling by liquid nitrogen. The corresponding mechanism of rolling was proposed. One possibility is the formation of ice crystals during the shock cooling process in liquid nitrogen to be the driving force.

Water-bath assisted convective assembly of aligned silver nanowire films for transparent electrodes.

Manipulating Ag nanowire (AgNW) assembly to tailor the opto-electrical properties and surface morphology could improve the performance of next-generation transparent conductive electrodes. In this paper, we demonstrated a water-bath assisted convective assembly process at the temporary water/alcohol interface for fabricating hierarchical aligned AgNW electrodes. The convection flow plays an important role during the assembly process.

Enhanced photovoltaic performance of organic/silicon nanowire hybrid solar cells by solution-evacuated method.

A method has been developed to fabricate organic-inorganic hybrid heterojunction solar cells based on n-type silicon nanowire (SiNW) and poly (3,4-ethylenedioxythiophene):poly (styrenesulfonate) (PEDOT:PSS) hybrid structures by evacuating the PEDOT:PSS solution with dip-dropping on the top of SiNWs before spin-coating (solution-evacuating). The coverage and contact interface between PEDOT:PSS and SiNW arrays can be dramatically enhanced by optimizing the solution-evacuated time. The maximum power conversion efficiency (PCE) reaches 9.

Improved color rendering of phosphor-converted white light-emitting diodes with dual-blue active layers and n-type AlGaN layer.

An InGaN/GaN blue light-emitting diode (LED) structure and an InGaN/GaN blue-violet LED structure were grown sequentially on the same sapphire substrate by metal-organic chemical vapor deposition. It was found that the insertion of an n-type AlGaN layer below the dual blue-emitting active layers showed better spectral stability at the different driving current relative to the traditional p-type AlGaN electron-blocking layer. In addition, color rendering index of a Y3Al5O12:Ce3+ phosphor-converted white LED based on a dual blue-emitting chip with n-type AlGaN reached 91 at 20 mA, and Commission Internationale de L'Eclairage coordinates almost remained at the same point from 5 to 60 mA.

Ultrathin nickel oxide film as a hole buffer layer to enhance the optoelectronic performance of a polymer light-emitting diode.

In order to promote a polymer LED (PLED), we fabricated and introduced an ultrathin nickel oxide (NiO) buffer layer (<10 nm) between the indium tin oxide (ITO) anode and the poly (3, 4-ethylenedioxythiophene) hole injection layer in the PLED. The NiO buffer layer was easily formed on the ITO anode by electron-beam deposition of a nickel (Ni) metal source and an oxygen plasma treatment process. As a result, the PLED device with the NiO buffer layer on its ITO anode had the same turn-on voltage as conventional PLED devices without the NiO buffer layer, and the luminance of the PLED device with the NiO buffer layer was doubled, compared with the conventional PLED devices without the NiO buffer layer.

Efficient green electrophosphorescence with Al cathode using an effective electron-injecting polymer as the host.

Efficient green phosphorescent polymer light-emitting diodes (PLED) based on aluminum (Al) cathode were demonstrated. The device composed of neutral aminoalkyl substituted polyfluorene, poly[(9,9-bis(3'-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)] (PFN) as the host and an Ir complex, fac-tris(2-(4-tert-butyl)-phenylpyridine)iridium (Ir(Bu-PPy)(3)), as the dopant. High luminous efficiency of 35.

A solution process for size-controlled growth and transfer of organic nanostructures with manufacture scalability.

A simple and robust process has been developed to control the growth of the organic nanowires in situ self-assembled in a polymer matrix, lift off the nanostructure/polymer composite film from the mother substrate for storage and transfer, and remove the polymer host prior to usage. Every step was completed through a solution process, which ensured the process's simplicity and low cost. The realization of large-sized nanowire/polymer composite film demonstrated the necessary process scalability required by the industrial roll-to-roll manufacturing.