As the car entered the tunnel, Cui Yanbin, sitting in the driver's seat, took off his sunglasses. Two minutes later, as the vehicle emerged from the tunnel, he put his sunglasses back on. Reflecting on the hassle of taking them off and putting them back on, he had a thought: could a film be developed to be applied to car windows that could automatically switch based on light and angle?
Inspired by a chance discovery and years of perseverance, Cui Yanbin, a researcher at the Institute of Process Engineering of the Chinese Academy of Sciences, and his team finally developed this miraculous "film" and entered the stage of transforming scientific research achievements.
Empowering the Colorful World
The application of electrochromic materials is making its way into various aspects of life. From architectural windows to electrochromic eyeglasses, from car windows to the dimming windows of the Boeing 787 commercial aircraft, electrochromic materials, replacing traditional static windows, can change the color and transparency of glass, significantly enhancing user experience.
So, how do electrochromic materials achieve the color-changing function?
Cui Yanbin told the "China Science Daily" that under the influence of an external electric field, electrochromic materials exhibit different responses to light. When subjected to an electric field or current, the optical properties of these materials undergo continuous reversible changes, causing the material to display different colors – this is electrochromic materials.
Flexible electrochromic devices have advantages such as small size, light weight, and flexibility. They also have broad application prospects in wearable devices, curved displays, energy saving, and adaptive camouflage.
Cui Yanbin vaguely felt that this interesting project might have significant market demand. After further research, he found that this technology could be expanded to more application scenarios. "With the increasing demand for energy conservation and emission reduction, various buildings need to achieve breakthroughs in reducing energy consumption and carbon emissions. Energy saving, emission reduction, and low-carbon environmental protection have also become one of the core requirements of flexible electrochromic technology."
Take traditional windows, for example. To meet the needs of adjusting light and improving indoor environments, curtains need to be installed, which not only require manual adjustment but also struggle to meet the requirements of energy conservation and emission reduction. By applying flexible electrochromic materials to architectural windows, automatic dimming, light blocking, heat insulation, and significant reduction in building energy consumption can be achieved.
Through technical verification, Cui Yanbin's team reaffirmed the feasibility of this innovative project and their determination to continue exploring. From preparing for the project, conducting research, finding materials, to numerous experiments and continuous optimization, they delved into the lengthy research and development of flexible electrochromic materials.
Addressing Market Demand
Recalling the "three major challenges" faced in material development, Cui Yanbin still feels deeply moved.
Firstly, the response time of flexible electrochromic materials is long, while application scenarios require rapid switching, necessitating the shortening of material response time. Secondly, the need to extend the material's lifespan to meet high-frequency switching requirements. Lastly, the challenge of material encapsulation needs to be addressed.
The electrochromic device transitions from transparent to blue and from blue to transparent. The interviewee provided a diagram.
After years of exploration, they successfully developed the technology for "flexible electrochromic materials" and overcame key technical challenges, leading the project into the stage of commercialization.
"Currently, the market mainly offers rigid electrochromic materials with response times typically in the range of minutes. The materials we developed can achieve a response time of around 2 seconds and over 5000 switches. Our next goal is to enhance material stability, achieving stable cycling of over 10,000 switches between transparent and colored states. This is what the market needs in flexible electrochromic materials," said Cui Yanbin.
He also revealed that the team is simultaneously developing an all-solid-state flexible electrochromic device to prevent performance degradation caused by "leakage" in electrochromic devices. Currently, the relevant technical pathways have been established, and the preparation of all-solid-state flexible electrochromic devices has been achieved in the laboratory.
The team led by Cui Yanbin, as shown by the interviewee-provided image
As technology continues to mature, in order to expedite the commercialization of flexible electrochromic materials, the team led by Cui Yanbin has also participated in the 2021 "CAS Concept Verification Program" guided and supported by the Science and Technology Innovation Development Center of the Chinese Academy of Sciences (formerly Beijing Branch) and the Zhongguancun Science City Management Committee.
The relevant person in charge of the Zhongke Zhihui Workshop stated, "Since its launch in 2020, the 'CAS Concept Verification Program' has been providing concept verification services such as seed funding, business consulting, entrepreneurial education, industry resource docking, investment and financing services, and incubation space, to select and support early-stage projects, promoting basic research with market potential from the laboratory to market application."
"We are very confident in this technology and its broad market prospects. The next step will involve continuous research and exploration to enrich the variety of colors, improve natural light intensity, innovate anti-peeping methods, and add a colorful experience to the world," said Cui Yanbin.
