手性胺铅卤化物有机-无机杂化钙钛矿型分子铁电及铁电光伏

Solar energy is an important renewable energy, and silicon photovoltaic (PV) cell is an important form of solar energy utilization. But only light with more energy than the bandgap can produce current, thus leading to the photoelectric conversion rate can not be further improved. The ferroelectric materials with spontaneous polarization are capable of producing ferroelectric photovoltaic (FE-PV) effect, which is completely different from the silicon p-n junction interface of PV effect. Among them, organic inorganic hybrid perovskite materials with unique molecular crystals structure were attracted more concerns due to they have special FE-PV effect. In this proposal, we will use the potentially excellent photoelectric properties and ferroelectric properties in organic inorganic hybrid pervoskite type compounds to design and synthesis the organic amine + PbX2 hybrid molecules with room temperature ferroelectircity and efficient PV effect. Using the chiral amine to induce ferroelectric; using the electron motion in halide pervoskite of Pb configuration to produce PV effect; the used of organic and inorganic two dimensional adjustable spacing to obtain suitable band gap width. The main purpose is to synthesis of room temperature FE-PV materials; to study the effect on the PV effect of ferroelectric domain, to reveal the relationship between ferroelectric and PV effect, to improve the photoelectric conversion efficiency. It is of great theoretical and practical significance on the development of ferroelectric materials and the application of organic inorganic hybrid solar cell semiconductor.

太阳能是一种重要的可再生能源，硅基光伏电池是利用太阳能的重要形式，但只有能量超过带隙的光才能产生电流，因此导致了光电转化率无法进一步提高。而铁电材料具有自发极化，能够产生铁电光伏效应，这是完全不同于硅p-n结的界面光伏效应。这其中，具有独特晶体结构的有机无机杂化钙钛矿型分子铁电材料所展现出的铁电光伏效应备受关注。在本申请中我们将利用有机无机杂化钙钛矿型化合物潜在的优良光电性能和铁电性能，设计合成兼具室温铁电性与高效光伏效应的有机胺+PbX2卤化物杂化钙钛矿型化合物。利用手性有机胺诱导产生铁电性，利用Pb卤化物钙钛矿构型电子运动性产生光伏效应，利用有机无机二维可调层间距获得合适的带隙宽度。主要目的是合成室温铁电光伏材料，研究铁电畴在光伏效应中的作用，揭示铁电性与光伏效应之间的关系，提高光电转化效率。本申请对有机无机杂化铁电材料及太阳能半导体电池的发展具有重大理论与实际意义。

铁电材料具有自发极化，能够产生铁电光伏效应，这其中，具有独特晶体结构的有机无机杂化钙钛矿型分子铁电材料所展现出的铁电光伏效应备受关注。在本申请中我们将利用有机无机杂化钙钛矿型化合物潜在的优良光电性能和铁电性能，设计合成兼具室温铁电性与高效光伏效应的有机胺+PbX2卤化物杂化钙钛矿型化合物。尽管自2009年以来，有机-无机杂化钙钛矿（OIHP）的研究关注度呈指数级增长，但高温相变OIHP仍然是一个不可逾越的难题。在此，通过2,5-二氟苄胺（2,5-FBA）和2,4-二氟苄胺（2,4-FBA）与氯化铅或溴化铅在浓HCl或HBr中反应，制备了一系列具有高相转变温度（Tc）的A2BX4型OIHP材料[(2,4-FBA)2PbCl4] (1), [(2,5-FBA)2PbBr4] (2), [(2,5-FBA)2PbCl4] (3), [(2,5-FBA)2PbBr4] (4)。有机阳离子上的氟原子增加了Tc。差示扫描量热法（DSC）和介电测量揭示了1-4的结构转变。变温单晶衍射和PXRD分析表明，1-4的不同物理性质来源于F原子在苄胺上不同的取代位置。