Microwave heating synthesis of HgS and PbS nanocrystals in ethanol solvent

A novel route was developed to prepare PbS and HgS nanocrystals in ethanol solvent in the presence of sodium hydroxide by microwave heating method. PbS and HgS nanocrystals were obtained with an average size of approximately 10 and 6 nm, respectively. In the reaction, mercury acetate and lead acetate were used as mercury and lead source; sulfur powder was employed as chalcogenide source. The products were characterized by X-ray powder analysis (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and UV–Vis absorption spectroscopy. The probable mechanism was presented.     

PbS和PbO反应动力学及其机理SCIEI

本文得出了PbS和PbO交互反应的速率方程:(da)/(dt)=kx_(PbS)~3x_(PbO)^(-2);发现了反应过程中有过渡产物碱式硫酸铅(PbSO_4·2PbO);从电子转移角度,探讨了反应机理。     

基于Ⅳ-Ⅵ族化合物的胶体量子点太阳电池研究进展

基于Ⅳ-Ⅵ族化合物的胶体量子点具有易于合成、带隙可调等优点,被认为是一种非常有前途的窄带隙光伏材料。近年来,利用Ⅳ-Ⅵ族化合物制作的胶体量子点太阳电池最高转换效率已经突破10%。介绍了胶体量子点的合成方法、基本结构及其光电特性;着重分析了国内外关于肖特基和异质结胶体量子点太阳电池的研究现状,指出了目前该领域研究中存在的问题和发展趋势,并分析了未来需要重点解决的关键问题。     

Synthesis and optical properties of ordered 30 nm PbS nanowire arrays fabricated into sulfuric anodic alumina membrane

Crystalline PbS nanowire arrays have been successfully fabricated by AC applied DC electrochemical deposition from aqueous solutions of dimethylsulfoxide DMSO solution containing lead chloride and elemental sulfur into sulfuric anodic alumina membranes (AAM). These nanowires have uniform diameters of approximately 30 nm, and their lengths are up to tens of micrometers. Scanning electron microscopy indicates that the ordered PbS nanowire arrays are completely embedded. The results of X-ray diffraction show that the as-synthesized nanowires are crystalline with highly preferential orientation. Energy dispersive spectrometer analysis shows that the composition ratio is very close to 1:1. Finally PL and UV–VIS illustrate the quantum confinement effects of PbS nanowire arrays.     

一种除铜新工艺在粗铅精炼中应用研究

针对西北铅锌厂粗铅火法精炼过程中,直接加单质硫进行除铜而出现硫损过大的问题,对除铜工艺中硫的利用方式进行了研究,提出一种除铜新工艺,即利用硫化铅代替单质硫进行除铜.在本实验中,对硫加入过量率、加热温度、加热时间等制备PbS的工艺条件进行了研究,并确定了加PbS除铜工艺的最佳硫化铅用量,最佳搅拌时间等技术条件.实验结果表明,粗铅中含铜量由0.814%下降至0.011%,除铜效率高达98.65%,且在除铜过程中,硫的利用率达92%以上.     

Effect of annealing temperature and graphene concentrations on photovoltaic and NIR-detector applications of PbS/rGO nanocomposites

The effect of annealing temperature on photovoltaic and near-infrared (NIR) detector applications of PbS nanoparticles (NPs) and PbS/graphene nanocomposites was investigated. The products were synthesized by a simple co-precipitation method and graphene oxide (GO) sheets were used as graphene source. Several characterization techniques were used to show transfer of the GO into reduced graphene oxide (rGO) during the synthesis process. In addition, the effect of graphene concentrations on morphology, structure, photovoltaic, and detector parameters of the samples were studied. Transmission electron microscope (TEM) images showed that, the PbS NPs were agglomerated, while, the PbS/rGO nanocomposites were dispersed completely after annealing under H₂/Ar gas atmosphere. UV–visible spectrometer showed an absorption peak for all samples in the near infrared red (NIR) region of the electromagnetic spectrum. The results indicated that, photocurrent intensity, responsivity of the samples to an NIR source, and solar-cell efficiency were affected by annealing of samples and graphene concentrations.     

Biomolecule and surfactant-assisted hydrothermal synthesis of PbS crystals

PbS crystals were hydrothermally synthesized using Pb(NO₃)₂, l-cysteine, and N-cetyl pyridinium chloride in solutions with different pH values at 140 °C. Flower-like, granular and truncated cubic PbS crystals composing of Pb and S were detected using an X-ray diffractometer (XRD), a scanning electron microscope (SEM), a transmission electron microscope (TEM), a selected area electron diffraction (SAED) technique and an energy dispersive X-ray (EDX) analyzer. In addition, a Raman spectrometer revealed the presence of the first and second overtone modes at 436 and 602 cm⁻¹, respectively. Emission spectra of the products were detected at 412 nm using a photoluminescence (PL) spectrometer.     

红外敏感硫化铅薄膜的化学机理探讨

硫化铅(PbS)薄膜光电性能的好坏决定了探测器的性能水平。PbS薄膜是制作PbS红外探测器的核心和基础,也是一直以来PbS探测器改进和提高的研究方向。分析了高温法、柯达法和联氨法共3种化学工艺形成硫化铅膜的反应机理。结果表明,光敏薄膜都涉及到PbSO4的形成。X-RD衍射测试结果证明硫化铅多晶薄膜中存在PbSO4,因此提出含有低浓度PbSO4的PbS固溶体的形成是光敏薄膜具有光敏特性的原因之一。     

Low temperature fabrication of hybrid solar cells using co-sensitizer of perovskite and lead sulfide nanoparticles

Our cost-effective approach for hybridizing methylammonium lead iodide and PbS nanoparticles at low temperature (≤100 °C) for photovoltaic devices is introduced. As employed into a perovskite based solar cell platform, effects of PbS on the device performance were investigated. Through experimental observations under simulated air-mass 1.5G illumination (irradiation intensity of 100 mWcm⁻²), the efficiency of a perovskite:PbS device is 11% higher than that of a pristine perovskite solar cell under the same fabrication conditions as a result of the broadened absorption range in the infrared region. The highest photovoltaic performance was observed at a PbS concentration of 2% with an open-circuit voltage, short-circuit current density, fill factor, and power-conversion efficiency of 0.557 V, 22.841 mA cm⁻², 0.55, and 6.99%, respectively. Furthermore, PbS NPs could induce hydrophobic modification of the perovskite surface, leading to an improvement of the device stability in the air. Finally, the low-temperature and cost-effective fabrication process of the hybrid solar cells is a good premise for developing flexible/stretchable cells as well as future optoelectronic devices.