A feasible and effective solution-processed PCBM electron extraction layer enabling the high VOC and efficient Cu_(2)ZnSn(S, Se)_(4) devices

Photo-generated carrier recombination loss at the CZTSSe/Cd S front interface is a key issue to the opencircuit voltage(V_(OC)) deficit of Cu_(2)ZnSnS_(x)Se_(4-x)(CZTSSe) solar cells. Here, by the aid of an easy-handling spin-coating method, a thin PCBM([6,6]-phenyl-C61-butyric acid methyl ester) layer as an electron extraction layer has been introduced on the top of CdS buffer layer to modify CZTSSe/CdS/ZnO-ITO(In_(2)O_(3):Sn) interfacial properties. Based on Sn^(4+)/DMSO(dimethyl sulfoxide) solution system, a totalarea efficiency of 12.87% with a VOC of 529 m V has been achieved. A comprehensive investigation on the influence of PCBM layer on carrier extraction, transportation and recombination processes has been carried out. It is found that the PCBM layer can smooth over the Cd S film roughness, thus beneficial for a dense and flat window layer. Furthermore, this CZTSSe/Cd S/PCBM heterostructure can accelerate carrier separation and extraction and block holes from the front interface as well, which is mainly ascribed to the downward band bending of the absorber and a widened space charge region. Our work provides a feasible way to improve the front interfacial property and the cell performance of CZTSSe solar cells by the aid of organic interfacial materials.

Effect of infusion pressure during cataract surgery on ganglion cells measured using isolated-check visual evoked potential

AIM： To detect the relationship between infusion pressure and postoperative ganglion cells function.METHODS： This prospective observational cohort study included sixty-one eyes that underwent uncomplicated cataract surgery. Patients were divided into two groups according to infusion time（IT） recorded using surgery equipment [Group A： IT〉IT_（mean）（27 eyes）; Group B： IT

Quality oriented multimode processes monitoring based on a novel hierarchical common and specific structure with different order information

Due to higher demands on product diversity,flexible shift between productions of different products in one equipment becomes a popular solution,resulting in existence of multiple operation modes in a single process.In order to handle such multi-mode process,a novel double-layer structure is proposed and the original data are decomposed into common and specific characteristics according to the relationship between variables among each mode.In addition,both low and high order information are considered in each layer.The common and specific information within each mode can be captured and separated into several subspaces according to the different order information.The performance of the proposed method is further validated through a numerical example and the Tennessee Eastman(TE)benchmark.Compared with previous methods,superiority of the proposed method is validated by the better monitoring results.

Cu_(2)O作为空穴提取层修饰BiVO_(4)光阳极以增强电荷分离和转移

光生电荷的分离和转移被认为是影响BiVO_(4)基光阳极光电性能的核心因素之一.本文设计了在BiVO_(4)光阳极与析氧助催化剂之间插入空穴提取层的方法.Cu_(2)O作为空穴提取层引入到助催化剂层(FeOOH/NiOOH)和BiVO_(4)之间,可以有效优化空穴的迁移路径,延长光生空穴的寿命,从而提高电极的光电化学性能.与BiVO_(4)相比,调整后的BiVO_(4)/Cu_(2)O/FeOOH/NiOOH光阳极的电荷分离效率从70.6%提高到了92.0%.此外,该光阳极在1.23 VRHE(AM 1.5G照明下)下,还显示出了3.85 mA cm^(-2)的高光电流密度,是BiVO_(4)的2.77倍.我们的研究结果表明,电沉积Cu_(2)O空穴提取层是一种简单且可扩展的方法,能够有效提高BiVO_(4)的光电活性,可用于太阳能驱动水分解领域.

An effective graph and depth layer based RGB-D image foreground object extraction method

We consider the extraction of accurate silhouettes of foreground objects in combined color image and depth map data.This is of relevance for applications such as altering the contents of a scene,or changing the depths of contents for display purposes in 3DTV,object detection,or scene understanding.To

Lignin-based polymer with high phenolic hydroxyl group content prepared by the alkyl chain bridging method and applied as a dopant of PEDOT

Inspired by the importance of the phenolic group to the electron transporting property of hole transport materials,phenolic hydroxyl groups were introduced in lignosulfonate(LS)via the alkyl chain bridging method to prepare phenolated-lignosulfonate(PLS).The results showed that the phenolic group was boosted from 0.81 mmol∙g^(–1) of LS to 1.19 mmol∙g^(–1) of PLS.The electrochemical property results showed two oxidation peaks in the cyclic voltammogram(CV)curve of PLS,and the oxidation potential of the PLS-modified electrode decreased by 0.5 eV compared with that of LS.This result indicates that PLS is more easily oxidized than LS.Based on the excellent electron transporting property of PLS,PLS was applied as a dopant in poly(3,4-ethylenedioxythiophene)(PEDOT,called PEDOT:PLSs).PLS showed excellent dispersion properties for PEDOT.Moreover,the transmittance measurement results showed that the transmittance of PEDOT:PLSs exceeded 85%in the range of 300–800 nm.The CV results showed that the energy levels of PEDOT:PLSs could be flexibly adjusted by PLS amounts.The results indicate that the phenolic hydroxyl group of lignin can be easily boosted by the alkyl chain bridging method,and phenolated lignin-based polymers may have promising potential as dopants of PEDOT to produce hole transporting materials for different organic photovoltaic devices.

Graded interface engineering of 3D/2D halide perovskite solar cells through ultrathin(PEA)_(2)PbI_(4) nanosheets

2D halide perovskites have emerged as promising materials because of their stability and passivation effect in perovskite solar cells(PSCs).However,the introduction of bulky organic ammonium cations from 2D halide perovskites would decrease the device performance generally compared to the traditional 3D MAPbI_(3).Incorporation of ultrathin 2D halide perovskite nanosheets(NSs)with 3D MAPbI_(3)could address this issue.Herein,we re port a rationally designed PSCs with dimensional graded 3D/2D MAPbI_(3)/(PEA)_(2)PbI_(4)heterojunction,in which 2D(PEA)_(2)PbI_(4)NSs were synthesized and incorporated between 3D MAPbI_(3)and hole-transporting layer.Besides the significantly improved stability,a notable increasement in power conversion efficiency(PCE)of 20%was obtained for the 3D/2D perovskite solar cells due to the favourable band alignment among(PEA)_(2)PbI_(4)NSs and the other components.The graded structure of MAPbI_(3)/(PEA)_(2)PbI_(4)would upshift the energy level continuously,which enhances the hole extraction efficiency thus reduces the interface charge recombination,leading to the increasements of VOC from1.04 V to 1.07 V,Jsc from 21.81 mA/cm^(2) to 23.15 mA/cm^(2) and the fill factor from 67.89% to 74.78%,and therefore an overall PCE of 18.53%.