对初中数学“求值问题”的解题方法探究

求值问题繁杂多样,但选择恰当的解题方法能快速、有效地解决问题.这就需要在平时的教学中掌握一定的解题技巧与方法.     

无机化学教学中绿色化学理念的渗透

绿色化学是一种战略思想或一种理念,绿色化学是化学教学的重要组成部分。简要介绍了绿色化学教育的意义和发展状况;提出了高等师范教育无机化学课程教学中渗透绿色化学理念的具体措施和途径。     

Reveal the large open-circuit voltage deficit of all-inorganicCsPbIBr2 perovskite solar cells

Due to excellent thermal stability and optoelectronic properties, all-inorganic perovskite is one of the promising candidates to solve the thermal decomposition problem of conventional organic—inorganic hybrid perovskite solar cells (PSCs), but the larger voltage loss (V_loss) cannot be ignored, especially CsPbIBr₂, which limits the improvement of efficiency. To reduce V_loss, one promising solution is the modification of the energy level alignment between the perovskite layer and adjacent charge transport layer (CTL), which can facilitate charge extraction and reduce carrier recombination rate at the perovskite/CTL interface. Therefore, the key issues of minimum V_loss and high efficiency of CsPbIBr₂-based PSCs were studied in terms of the perovskite layer thickness, the effects of band offset of the CTL/perovskite layer, the doping concentration of the CTL, and the electrode work function in this study based on device simulations. The open-circuit voltage (V_oc) is increased from 1.37 V to 1.52 V by replacing SnO₂ with ZnO as the electron transport layer (ETL) due to more matching conduction band with the CsPbIBr₂ layer.