Diluted chemical bath deposition of CdZnS as prospective buffer layer in CIGS solar cell

In this study, dilute chemical bath deposition technique has been used to deposit CdZnS thin films on soda-lime glass substrates. The structural, morphological, optoelectronic properties of as-grown films have been investigated as a function of different Zn²⁺ precursor concentrations. The X-ray diffractogram of CdS thin-film reveals a peak corresponding to (002) plane with wurtzite structure, and the peak shift has been observed with the increase of the Zn²⁺ concentration upon formation of CdZnS thin film. From morphological studies, it has been revealed that the diluted chemical bath deposition technique provides homogeneous distribution of film on the substrate even at a lower concentration of Zn²⁺. Optical characterization has shown that the transparency of the film is influenced by Zn²⁺ concentration and when the Zn²⁺ concentration is varied from 0 M to 0.0256 M, bandgap values of resulting films range from 2.42 eV to 3.90 eV while. Furthermore, electrical properties have shown that with increasing zinc concentration the resistivity of the film increases. Finally, numerical simulation validates and suggests that CdZnS buffer layer with composition of 0.0032 M Zn²⁺ concentration would be a promising candidate in CIGS solar cell.     

Optoelectronic devices towards monolithic integration

Starting from the present state-of-the-art of discrete devices up to the realization of monolithic semiconductor integrated prototypes, an overview of optoelectronic devices for telecommunications is given. Among discrete devices single frequency lasers, tunable and multi-sectionDFB lasers andPIN andAPD photodiode detectors are analysed, including the use of new technologies in progress for a second generation of devices. On the future perspective ofIBCN distribution networks, some economics of the hybrid and monolithic form of integration are attempted. Finally a short outline of the most recent achievements in monolithic integration is presented, taking into particular consideration the activities in this field byEEC ESPRIT andRACE programmes.     

薄膜波导光隔离器和光电子单片集成技术

叙述了Ｂｉ，Ａｌ：ＹＩＧ薄膜的液相外延生长，研究了这种薄膜材料的光吸收系数、法拉第旋转角、磁光优值及生长感生磁各向异性与Ｂｉ含量的关系。在此基础上，连续外延生长了作单模磁光波导的双层Ｂｉ，Ａｌ：ＹＩＣ薄膜。光纤偏振器的使用使薄膜波导光隔离器向实用化迈进了一步，恒磁薄膜作偏磁场为器件集成化作出了贡献。采用ＭＯＣＶＤ技术，在ＧＧＧ（钆镓石榴石）基片上同时外延生长Ⅲ－Ⅴ族半导体薄膜和钇铁石榴石（ＹＩＧ）薄膜，把光隔离器和磁光光源直接集成在一起，是一种非常有前景的光电子集成组件。     

同轴型光电器件的研究开发

本文简要地介绍了武汉电信器件公司正在研究开发的同轴型光电器件，新的器件的工艺与结构特点以及主要技术指标、使用前景。     

工业电视摄像机在钢管质量检测中的应用

本文介绍了一种在工业中检测细长钢管内表面质量的光电检测设备。该设备利用工业电视摄像机来提取被检测钢管内表面的图像信息，以IBM－PC／AT486机作为控制与图像处理系统，主要用于各种细长钢管内壁疵病的实时自动检测。     

Synthesis and red electrophosphorescence of a novel cyclometalated iridium complex in polymer light-emitting diodes

The preparation and characterization of a new cyclometalated iridium complex with 2-(1-naphthalene) pyridine ligand were reported. An electrophosphorescent device was fabricated by using this new iridium complex as guest and poly-(cyano-paraphenylene) as host. Red electrophosphorescence was observed with an emission peak at approximately 600 nm. An external quantum efficiency of 1.3% was achieved in this electrophosphorescent polymer light-emitting devices.     

Novel A-D-A type small molecules with β-alkynylated BODIPY flanks for bulk heterojunction solar cells

A serial of novel A-D-A type small molecules with BODIPY linked through alkynyl with various electron donor units such as fluorene, carbazole, benzodithiophene and phenothiazine, namely F-BDP, C-BDP, B-BDP and P-BDP, respectively, were designed and synthesized. Introducing the alkynyl bridge leads to extending the molecular absorption spectrum to the range of 320–700 nm with high molar extinction coefficients (10⁵ cm⁻¹ M⁻¹) and strong fluorescence quenching. The molecules showed relatively low HOMO ranging from −5.02 to −5.24 eV as estimated from cyclic voltammetry measurements. Interestingly, B-BDP with BDT as donor exhibits more obviously red-shifted absorption in the solid state compared to F-BDP, C-BDP and P-BDP. Furthermore, the solution-processed bulk-heterojunction organic solar cell based on B-BDP/PC₇₁BM present superior charge transport property and more favorable nanoscale morphology, resulting in a significant higher J_sc of 11.84 mA cm² and FF than the other counterparts, thus achieved a higher PCE of 4.65%, which is one of the best values among the ever reported BODIPY based organic solar cells.     

Stability of perovskite materials and devices

Due to the excellent optoelectronic properties, organic–inorganic perovskites have drawn much attention and have been applied in different electronics with remarkable performance. However, the poor stability creates a massive barrier for the commercialization of perovskite electronic devices. In this review, we discuss intrinsic and extrinsic factors causing instabilities of perovskites and perovskite devices such as solar cells, liquid crystal displays (LCDs), light emitting diodes (LEDs), ionizing radiation detectors, transistors, memristors and sensors. We further review the stabilization approaches, including composition engineering, adoption of lower dimensional compositions, quantum dots, interface engineering, defects engineering and so on.     

Analysis of optoelectronic and trasnport properties of magnesium based MgSc2X4 (X=S,Se) spinels for solar cell and energy storage device applications

Intense research work is underway for identifying materials with potential applications in energy storage and energy harvesting systems. The magnesium based scandium chalcogenides have recently emerged as potential candidates for Mg batteries owing to their high Mg ionic conductivity and low electron conduction. At the same time, their band gaps are capable of absorbing electromagnetic radiations in visible to UV range; making them suitable for solar cell applications. In order to analyze the application of MgSc₂X₄(X = S, Se) compounds in energy devices, in this work we employ density functional theory calculations using the full potential linear augmented plane-wave method for examining their optoelectronic and thermoelectric properties. For the structural properties, the generalized gradient approximation functional designed for solids (PBEsol-GGA) has been used, while modified Becke and Johnson (mBJ) potential functional is used for computing the optoelectronic and transport properties. Our calculated optical properties indicate that these materials can find applications in solar cells. Moreover, the electronic transport properties computed using Boltzmann transport equation suggest carrier concentrations in MgSc₂S₄ to MgSc₂Se₄ spinels can be tuned for making them suitable for metal ion batteries.