Van der Waals Thin Films

Xiangfeng Duan: My main roles entail designing research, troubleshooting experimental issues, interpreting results, and organizing and presenting findings.

Zhaoyang Lin: I initially assembled the van der Waals thin films using solution-processable 2D nanosheet ink materials, following the idea proposed by Professor Xiangfeng Duan 10 years ago. Then, I spent several years optimizing the 2D material synthesis, ink formulation, film assembly technique, and electronic device fabrication/measurement.

Zhaoyang Lin: Making a solution-processable inorganic semiconducting thin film that can simultaneously deliver competitive electronic performance and great flexibility/stretchability was certainly challenging. Representative milestones include the first demonstration of high-performance van der Waals thin films from solution-processable ink materials, the realization of nearly 50% stretchability, and application on plant leaves and human skin.

Zhuocheng Yan: The biggest challenges in this project involved two critical areas. Firstly, the fabrication of high-quality van der Waals thin films (vdWTFs) posed a significant challenge. Achieving broad-area plane-to-plane VDW contacts among defect-free 2D nanosheets to form uniform vdWTFs and ensuring excellent electronic and mechanical performance required advanced materials engineering and precise manufacturing process control. Secondly, integrating vdWTFs seamlessly with biological systems presented a complex challenge. This required ensuring that the films could not only conform to dynamic living organisms without causing damage or discomfort but also function effectively within the biological environment, maintaining stability and performance for reliable bioelectronic applications. These challenges demanded innovative solutions in materials science and bioengineering to realize the full potential of VDWTFs in bioelectronic applications.

Zhuocheng Yan: Our team was composed of individuals (MA and PhD students, as well as postdoctoral research fellows and visiting scholars) with expertise in chemistry, materials science, bioengineering, and flexible electronics. This diverse skill set allowed us to tackle complex problems from multiple angles, whether it was synthesizing the 2D nanosheet inks, assembling high performance 2D nanosheets to thin-film electronic components and merging vdWTFs electronic devices with living tissues.

Zhaoyang Lin: You can imagine next-generation electronic devices that can attach to the human skin just like tattoos. These devices not only monitor your health condition, body status, and surrounding environments but also work as an on-skin computer to analyze all the data and send the results to your phone and doctor. Although we are not there yet, our work has pushed us one step closer to this exciting future.

Zhuocheng Yan: This work is important and exciting because it bridges the gap between rigid, high-performance electronic materials and soft biological tissues, enabling the development of bioelectronics that can seamlessly interface with living plants, human skin, and other soft tissues. This has significant implications for intelligent agriculture, environmental monitoring, human health monitoring and medical devices, making our research highly impactful.

Zhaoyang Lin: Our research can help the development of wearable electronic devices which may find exciting applications in flexible displays, electronic skin, and wearable healthcare devices.

Zhuocheng Yan: The biggest impact of this technology is likely to be in the field of wearable electronics and personalised medicine. By enabling more conformal and comfortable electronic devices that can monitor health indicators in real time, our technology could revolutionise the way we track and manage personal health.

Zhuocheng Yan: In real life, our van der Waals thin films could be used in wearable biosensors for plants and humans. Merging vdWTFs with the human body enables skin-gate vdWTF transistors to monitor vital signs such as heart rate, muscle activity, and brain function and can be used in advanced medical patches. They also have potential applications in neural interfaces, soft robotics, and as interfaces for prosthetic devices.

Zhaoyang Lin: We are contacting potential industry partners and exploring commercialisation opportunities. And we hope to see the application of our stretchable van der Waals membrane in real life. Meanwhile, further efforts to improve the electronic performance of the film, material synthesis/manufacturing process, and prototypic devices are still ongoing in our group.

Zhuocheng Yan: Over the next few years, I see this technology (vdWTF bioelectronics) advancing towards more complex integrations with living systems, including intelligent agriculture and neural interfaces. There is also potential for scaling up the production process to enable widespread use in various consumer and medical applications, such as VR techniques and electronic skin for health monitoring.

Zhaoyang Lin: A collaborative, open, and inclusive environment is key to a good research culture so that each member can have the opportunity to fulfil their own potential in scientific research. It would be ideal if we could realize the worldwide collaboration to include more researchers and combine their efforts.

Xiangfeng Duan: The chemical sciences have played a critical role in the modern electronic industry. As we transition into the post-Moore or more-than-Moore era, the chemical sciences are poised to play an ever-increasing role in future electronic advancements. This includes the development of novel materials to propel ongoing progress in information technology and to usher in entirely new paradigms in quantum information science, as well as the creation of materials for emerging electronic formats and ubiquitous sensor networks that can seamlessly merge with soft biological systems and the human body. Importantly, advancements in the chemical sciences can help achieve these diverse goals in a manner that is less wasteful, more energy-efficient, or entirely renewable.

Xiangfeng Duan: Stay curious, questioning assumptions and never taking anything for granted. Maintain rationality, rejecting superstitions and embracing logic; Exercise critical thinking, challenging the status quo and seeking innovation. Pursue passion relentlessly and refuse to settle.