2023 English Lecture Series on Sustainable development and the future IV

On the evening of 23 March 2023, the English lecture series Sustainable Development and the Future continued at Tongji University's Siping Campus. For tonight's session, we are honoured to have Professor Huang Jia from the School of Materials of Tongji University presenting the keynote speech Magic Newspaper - Flexible Electronic Devices.

Figure 1: Professor Huang Jia explaining multi-junction solar cells

In the 21st century, mankind is faced with the major challenge of achieving sustainable economic and social development, the development of the economy has become a global hot issue under the dual constraints of limited resources and strict environmental protection requirements, and energy problems will become more prominent. In order to solve the energy problem and achieve sustainable development, we can only rely on scientific and technological progress, the large-scale development and use of renewable and clean energy, and solar energy has large reserves, universal, economic, clean and environmentally friendly advantages, so the use of solar energy has become more and more widely attached to people, becoming the ideal alternative energy. In this context, multi-junction compound semiconductor solar cells have become the most promising solar cells for terrestrial applications due to their high conversion efficiency, good temperature characteristics, low environmental pollution and large cost reduction space. In addition, solar cells have the disadvantage of generally low conversion efficiency and high prices, while multi-junction solar cells have great potential for achieving high conversion efficiencies and equally high potential in economic terms.

Figure 2: Professor Huang Jia explaining the tiny molecular structure changes

Portable, low cost, bendable and green - these are all important trends in current electronic products. Ordinary electronic components, such as chips made up of countless transistors, are generally made of inorganic semiconductor materials, such as transistorised silicon, which is hard and easily broken. Perhaps, in the near future, transparent and bendable electronic devices can be printed from renewable resources, i.e. paper-based electronics similar to the magic newspaper in Harry Potter or the bendable, foldable and fully transparent displays seen in science fiction films.

Figure 3: Professor Huang Jia explaining the six-junction solar cell

To sum up, solar cells are a green and environmentally friendly new energy method that is very conducive to sustainable development. However, due to the cost issue, the market has been very slow. In fact, with the improvement of science and technology in recent years, the cost of preparing the solar cell module itself has been greatly reduced, but the installation cost of the system is still high. The flexible thin-film solar cells have great advantages in terms of installation costs and portability. (Photo/text Liu Yongxiang)