CUHK Lives and Legends

36 W ong Tak-sing  is an engineer who takes a leaf out of nature’s book when looking for solutions to human problems. In 2014, he was named by MIT Technology Review  one of the top innovators under the age of 35 with the invention of Slippery Liquid- Infused Porous Surfaces (SLIPS), a liquid-repellent coating modelled after the carnivorous pitcher plant that uses its slippery leaves to capture prey. The invention, hailed as ‘one of today’s most intriguing and potentially useful new materials’, had its genesis 18 years earlier in the Faculty of Engineering of CUHK. In 2000, when Tak-sing was still a freshman at the then Department of Automation and Computer- Aided Engineering, he came across nanotechnology in the Basic Electronics course taught by Prof. Li Wen-jung . ‘On the last day of class, Professor Li showed us a range of close-up photos taken under an electron microscope. They totally blew me away. One of them had an ant holding on to a delicate gear that was even smaller than the bug itself. I was immensely intrigued by the idea of creating devices that tiny. After class I drafted a proposal on how I intended to make a micro- scale flying robot, and e-mailed it to Professor Li.’ The professor immediately took a shine to this assiduous and aspiring student, and soon introduced him to laboratory research. ‘It was rare for an undergraduate, and even rarer for a freshman, to get into a research group. In retrospect, I wonder why Professor Li would trust me in not messing up any of his state-of-the-art research equipment,’ said Tak-sing, half-jokingly. Upon graduation, he chose to move thousands of miles from home to earn a doctorate at UCLA under the supervision of Prof. Ho Chih- ming who was once the PhD advisor of Li. ‘I had always been looking up to Professor Li and admiring his style of mentorship. It was really fortunate that I could follow in his footsteps and learn from my mentor’s mentor,’ said Tak-sing. By the end of his studies at UCLA, Tak-sing started to take an interest in biomimicry—a discipline that looks to nature for clues in solving technical conundrums. ‘I came to realize that nature is a master of nanotechnology. From the sticky toes of a gecko to the water-repellent leaves of a lotus leaf, many creatures c c SLIPS coating is modelled after the carnivorous pitcher plant ‘The natural world is using nanotechnology on a daily basis to solve complex problems.’ in the natural world utilize micro- and nanostructures to perform special functions, and that became the topic of my PhD thesis.’ In 2010, Tak-sing moved to Boston to work at the Wyss Institute for Biologically Inspired Engineering at Harvard University. A year later, under the guidance of his postdoctoral adviser  Joanna Aizenberg , he developed the non- stick surface SLIPS. Just like its sibling in the plant world—the pitcher plant that lures unsuspecting ants