联系我们  |  网站地图  |  English   |  移动版  |  中国科学院 |ARP
站内搜索:
首页 简介 管理部门 科研部门 支撑部门 研究队伍 科研成果 成果转化 研究生教育 党建与创新文化 科普 信息公开 办公内网
科技信息
Low-cost wearables manuf...
Researchers develop 3-D-...
硫化钴能用来制作超级电容
青岛能源所在石墨炔能源存...
二维非铅钙钛矿动力学机理...
Scientists fine-tune sys...
Amorphous diamond synthe...
化学耦合的硫化镍和碳空心...
全无机钙钛矿光电探测器动...
科研人员提出纳米催化医学...
Newly-discovered semicon...
Molecular nanoparticles ...
碳纳米点固态高效发光新方法
基于甲胺气体的钙钛矿薄膜...
新型镁电池可使储能技术更...
现在位置:首页>新闻动态>科技信息
Flatter materials have fewer imperfections, which makes for better solar cells and light sensors
2017-08-15 09:17:05 | 编辑: | 【 【打印】【关闭】

 

Improving the efficiency of materials will help to further advancements in designing and optimizing perovskite solar cells. Credit: KAUST

  Improving the efficiency of solar cells requires materials free from impurities and structural defects. Scientists across many disciplines at KAUST have shown that 2-D organic-inorganic hybrid materials feature far fewer defects than thicker 3-D versions.

  Modern-day electronics rely on technologies that can develop almost perfect crystals of silicon; flawless to the atomic level. This is crucial because defects and impurities scatter electrons as they flow, which adversely affects the material's electronic properties.

  But hybrid perovskites, an exciting class of electronic material, cannot be constructed using the epitaxial or layer methods developed for silicon. Instead, they are produced using solution-based processes. While this makes them cheaper than silicon, it also makes purity much harder to achieve as defect population and species are sensitive to the processing conditions.

  Osman Bakr from the KAUST Solar Center together with colleagues from multiple divisions across KAUST and the University of Toronto, demonstrate that two-dimensional layers of perovskite material can achieve levels of purity much higher than is possible than in their 3-D counterpart. "Two-dimensional hybrid perovskites are a subgroup of the big hybrid perovskite family," explains Wei Peng, lead author and doctoral degree recipient from Bakr's lab. "They can be derived by inserting large organic cations in three-dimensional perovskite structures."

  Hybrid perovskites are made up of lead and halide (such as iodine) atoms and an organic component. This class of materials in solar cells has already shown ground-breaking potential for energy conversion efficiency while having low production costs and the possibility for being integrated in flexible devices. This combination of qualities makes hybrid perovskites an exciting material for optoelectronic applications.

  Peng, Bakr and coworkers created a 2-D material made of periodic layers of hybrid perovskites with an organic component of either phenethylammonium or methylammonium. Using a solution-based fabrication method, the layers were placed on a gold electrode so the team could measure the electrical conductivity.

  Their measurements indicate that the 2-D materials contained three orders of magnitude fewer defects than bulk hybrid perovskites. The team proposes that this reduction is because the large organic cations in the phenethylammonium suppress defect formation during crystallization.

  Next, the team demonstrated the potential for their materials for optoelectronic applications by constructing photoconductors with high light detectivity. These results bode well for further advancements in designing and optimizing perovskite solar cells. "A future in-depth study on how the defect formation is suppressed will help our understanding and benefit device performance-targeted materials engineering," says Peng.

  Explore further: Researchers hit new world efficiency record with perovskite solar cells 

  More information: Wei Peng et al. Ultralow Self-Doping in Two-dimensional Hybrid Perovskite Single Crystals, Nano Letters (2017). DOI: 10.1021/acs.nanolett.7b01475 

  Journal reference: Nano Letters 

版权所有 中国科学院上海硅酸盐研究所 沪ICP备05005480号
长宁园区地址:上海市长宁区定西路1295号 电话:86-21-52412990 传真:86-21-52413903 邮编:200050
嘉定园区地址:上海市嘉定区和硕路585号  电话:86-21-69906002 传真:86-21-69906700 邮编:201899