GLOBAL-Promoting Research Partnership in Fabrication of Advanced III-nitride Optoelectronics With Ultra Energy Efficiency Using Nanotechnology

全球促进利用纳米技术制造具有超高能效的先进III族氮化物光电子器件的研究伙伴关系

• 批准号: EP/K004220/1
• 负责人: Tao Wang
• 金额: $ 40.42万
• 依托单位: University of Sheffield
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2012
• 资助国家: 英国
• 起止时间: 2012 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FK004220%2F1
• 关键词: GLOBAL; Promoting; Research; Partnership; Fabrication

Our research has the potential to meet two major challenges which human beings are facing: energy crisis and climate change. Currently, the energy consumed due to general illumination accounts for 29% of the world's total energy consumption. Although the energy provided by an hour of solar radiation on the Earth is equivalent to the world's total energy consumption per year, solar cells contribute only 0.03% to the figure. Therefore, it is necessary to develop new technologies to achieve ultra energy-efficient solid-state lighting sources and solar cells. The appearance of III-nitride semiconductors provides human beings with such a unique opportunity, as the light emission from III-nitrides covers the complete visible spectrum and also a major part of the solar spectrum. It has been predicted that III-nitride LEDs if used in our homes and offices could save 15% of the electricity generated at power stations, 15% of the fuel used, and 15% reduction in carbon emission.For more than a decade substantial efforts have been devoted to developing high-brightness III-nitride LEDs (HB-LEDs) worldwide. Consequently, major achievements have been made. However, a fatal problem has appeared, and has to be solved urgently. That is the well-known "efficiency droop": the efficiency of HB-LEDs shows the highest value only at a low injection current, and a further increase in injection current leads to a significant reduction in efficiency. This is the "efficiency droop". Under the injection current required for practical applications, the efficiency drops down to >50% of the peak value, meaning that a large amount of energy has been wasted. This also causes a severe reliability issue, as the wasted energy leads to an elevated temperature of the devices and thus severe degradation in device performance. The physical origins of the efficiency droop are very complicated and thus unclear. So far, there is not any efficient solution. In the project, the scientists from 6 world-leading teams at University of Sheffield, Yale University (USA), Nanjing University (China) and Technology University of Braunschweig (Germany) are pooling their unique but complementary expertise, proposing to employ a number of advanced nanotechnologies and epitaxial growth techniques in order to explore the fundamental issue, and then achieve ultra energy-efficient LEDs. For solar cells, it has been predicted that an energy-conversion efficiency of >50% can be achieved with III-nitrides, which is much higher than that of any current solar cell. The solar energy-conversion efficiency of current III-nitride solar cells is extremely low, only ~3% in the best report due to a number of technologic challenges. We will combine our complementary expertise from 6 teams to tackle the challenges by employing a similar nanotechnology to fabricate into nanorod array solar cells on the epiwafers with a thick super-lattice structure on the GaN substrates with ultra-high crystal quality.

我们的研究有可能解决人类面临的两大挑战：能源危机和气候变化。目前，普通照明消耗的能源占世界总能源消耗的29%。虽然地球上一小时的太阳辐射所提供的能量相当于世界每年的总能量消耗，但太阳能电池只占这个数字的0.03%。因此，有必要开发新技术来实现超节能的固态照明光源和太阳能电池。iii -氮化物半导体的出现为人类提供了这样一个独特的机会，因为iii -氮化物的发光覆盖了整个可见光谱，也是太阳光谱的主要部分。据预测，如果在我们的家庭和办公室使用iii -氮化物led，可以节省15%的发电站发电量，15%的燃料使用量，并减少15%的碳排放。十多年来，人们一直致力于开发高亮度iii -氮化物led （hb - led）。因此，取得了重大成就。然而，一个致命的问题已经出现，亟待解决。这就是众所周知的“效率下降”：hb - led的效率只有在低注入电流时才会显示出最高的值，而注入电流的进一步增加会导致效率的显著降低。这就是“效率下降”。在实际应用所需的注入电流下，效率下降到峰值的50%，这意味着大量的能量被浪费了。这也会导致严重的可靠性问题，因为浪费的能量会导致设备温度升高，从而导致设备性能严重下降。效率下降的物理根源非常复杂，因此不清楚。到目前为止，还没有有效的解决办法。在该项目中，来自谢菲尔德大学、耶鲁大学（美国）、南京大学（中国）和布伦瑞克工业大学（德国）的6个世界领先团队的科学家们正在汇集他们独特但互补的专业知识，提出采用一些先进的纳米技术和外延生长技术来探索基本问题，然后实现超节能led。对于太阳能电池来说，据预测，使用iii -氮化物可以实现50%的能量转换效率，这远远高于目前任何一种太阳能电池。目前iii -氮化物太阳能电池的太阳能转换效率极低，由于许多技术挑战，在最好的报道中只有~3%。我们将结合来自6个团队的互补专业知识，通过采用类似的纳米技术在具有超高晶体质量的GaN衬底上具有厚超晶格结构的外延晶片上制造纳米棒阵列太阳能电池来应对挑战。

项目成果

Semi-polar InGaN/GaN multiple quantum well solar cells with spectral response at up to 560 nm

• DOI: 10.1016/j.solmat.2017.10.005
• 发表时间: 2018-02
• 期刊: Solar Energy Materials and Solar Cells
• 影响因子: 6.9
• 作者: J. Bai;Y. Gong;Z. Li;Yun Zhang;Tao Wang

Influence of the ITO current spreading layer on efficiencies of InGaN-based solar cells

• DOI: 10.1016/j.solmat.2015.10.026
• 发表时间: 2016-02
• 期刊: Solar Energy Materials and Solar Cells
• 影响因子: 6.9
• 作者: J. Bai;M. Athanasiou;Tao Wang

Effect of an ITO current spreading layer on the performance of InGaN MQW solar cells

• DOI: 10.1002/pssc.201510171
• 发表时间: 2016-01
• 期刊: Physica Status Solidi (c)
• 作者: J. Bai;M. Athanasiou;Tao Wang

Enhancement in solar hydrogen generation efficiency using a GaN-based nanorod structure

• DOI: 10.1063/1.4803926
• 发表时间: 2013-05
• 期刊: Applied Physics Letters
• 影响因子: 4
• 作者: J. Benton;J. Bai;Tao Wang

Utilisation of GaN and InGaN/GaN with nanoporous structures for water splitting

• DOI: 10.1063/1.4903246
• 发表时间: 2014-12-01
• 期刊: APPLIED PHYSICS LETTERS
• 影响因子: 4
• 作者: Benton, J.;Bai, J.;Wang, T.
• 通讯作者: Wang, T.