掺杂离子的种类对介孔La_(0.6)A_(0.4)NiO_3钙钛矿催化剂的结构与催化活性的影响

以十六烷基三甲基溴化铵(CTAB)为模板剂,用共沉淀法分别制备了介孔La_(0.6)A_(0.4)Ni O_3(A=Ce、Sr、Y、Nd、Pr)钙钛矿复合氧化物,用XRD、SEM、FTIR、BET和程序升温技术等对复合氧化物的晶相结构、表面形貌、表面积、孔径分布及表面性能等进行了表征,同时在蔗渣高压液化反应中探讨了A位离子掺杂种类对介孔La_(0.6)A_(0.4)Ni O_3催化活性和液化产物分布及液化油含量的影响。结果表明,掺杂的A位离子均能进行不同程度的同晶取代,其中掺杂的Pr^(3+)能较好的与La^(3+)发生同晶取代,且具有较大的比表面积和孔径分布,表面存在较强的氧物种传导性和碱性中心,在蔗渣高压液化反应中具有较高的液化油产率和较低的残渣率,生物质油的主要成分为乙酰柠檬酸三丁酯、柠檬酸三正丁酯、对乙基苯酚、6-乙基-3-肽酸酯,有利于提高油品的质量。

B位离子的种类对介孔La0.6Pr0.4BO3复合氧化物的催化性能影响

十六烷基三甲基溴化铵(CTAB)为模板剂,以共沉淀法分别制备了介孔La0.6Pr0.4BO3 (B = Mn2+, Cu2+, Co2+, Fe3+, Ni2+)钙钛矿复合氧化物,用XRD、FI-IR、BET和程序升温等技术对复合氧化物的晶相结构、表面积、孔径分布及表面性能等进行了表征,同时在蔗渣高压液化反应中探讨了B位离子种类对介孔La0.6Pr0.4BO3催化活性和液化产物分布及液化油产率的影响。结果表明,Mn2+离子掺杂制备的介孔La0.6Pr0.4MnO3特征衍射峰相对较强,样品的结晶度较高,孔道较好,具有较大的比表面积,为21.98 m2?g?1,最可几孔径为32.27 nm,表面存在较强的氧物种传导性和碱性中心,在蔗渣高压液化反应中液化油产率为59.68%,残渣率为12.62%。液化产物主要成分是对乙基苯酚、苯酚、对苯甲醇、邻愈创木酚。

探究消除离子抛光截面样品上波纹现象的方法

目前,氩离子束抛光制备截面样品凭借其易于获得大面积平整表面以及适用范围广等优势被人们广泛采用。本文以单晶硅片为典型样品,通过氩离子抛光制备硅片的截面样品探究了消除截面样品上波纹现象的方法。实验表明通过调整样品在挡板上粘接的凸出量并控制氩离子束流中中性快粒子的成分,可以有效增加在相同时间内离子束抛光的深度,消除截面区域的波纹,从而提高离子抛光制备截面样品的成功率。将上述离子抛光的规律推广应用到制备满足开尔文探针力显微镜测试要求的介孔钙钛矿太阳电池截面样品上,大大提高了制备介孔钙钛矿太阳电池截面样品的成功率。

Solution-processed perovskite solar cells

Perovskite solar cells(PSCs) have emerged as one of the most promising candidates for photovoltaic applications. Low-cost, low-temperature solution processes including coating and printing techniques makes PSCs promising for the greatly potential commercialization due to the scalability and compatibility with large-scale, roll-to-roll manufacturing processes. In this review, we focus on the solution deposition of charge transport layers and perovskite absorption layer in both mesoporous and planar structural PSC devices. Furthermore, the most recent design strategies via solution deposition are presented as well, which have been explored to enlarge the active area, enhance the crystallization and passivate the defects, leading to the performance improvement of PSC devices.

Unraveling the roles of mesoporous TiO2 framework in CH3NH3PbI3 perovskite solar cells

Both of planar and mesoporous architectures prevail for perovskite solar cells(PSCs).However,it is still an open question how the architecture affects the performance of PSCs.The inconsistent results in the references often create confusion.In particular,the specific roles of mesoporous frameworks are yet to be well elaborated and require further clarification.In this study,we carefully compared the properties of perovskite films and the device performances for both architectures to unravel the roles of mesoporous TiO2 framworks in CH3NH3PbI3 PSCs.The detailed characterizations of structural,microscopic,optical and electrical properties revealed that the presence of mesoporous TiO2 framework contributed to enlarged perovskite crystal sizes,enhanced light harvesting,efficient electron extration and suppressed charge recombination.As a result,compared with the planar device,the mesoporous device yielded an improved power conversion efficiency of 18.18%,coupled with a reduced hystersis.This study reveals the benefits of mesoporous TiO2 framework in PSCs and provides the guidance for the design and optimization of architectures for high-performance devices.

Rational design of SnO_2-based electron transport layer in mesoscopic perovskite solar cells:more kinetically favorable than traditional double-layer architecture

Here,the interfacial synergism of discontinuous spot shaped SnO_2 and TiO_2 mesoporous nanocomposite as electron transfer layer（ETL） underlayer is presented in highly efficient mesoscopic perovskite solar cells（M-PSCs）. Based on this new strategy,strong charge recombination observed in previous SnO_2-based ETLs is suppressed to a great extent as the pathways of charge recombination and energy loss are blocked effectively. Meanwhile,the internal series resistance of entire M-PSC is decreased remarkably. The new ETL is more kinetically favorable to electron transfer and thus results in significant photovoltaic improvement and alleviated hysteresis effect of M-PSCs.