As a professor at Jilin University, Xu Ruren spent his life teaching and researching chemistry. His involvement continued even after retirement when in 2017, Xu and his wife donated 5 million yuan ($770,000), nearly all their savings, to set up a fund at the university to support the study of inorganic synthetic chemistry. That dedication earned the 89-year-old two Jilin province awards for Moral Model and Good Man.

After graduating as a chemistry major from Shanghai Jiao Tong University in 1952, Xu began teaching inorganic chemistry. Over the years, he taught 12 undergraduate and graduate courses at Jilin University in Changchun, the provincial capital.

A firm believer that a teacher's most important role is to educate and cultivate students, he also believes that it is the teacher's duty to do everything related to teaching well."Teachers must take every single class seriously, make the proper preparations, and impart as much knowledge as possible to students," he said.

"If I'm spending my time on something, I might as well do it properly. I chose this job, so I should treat it with the respect and attention it deserves. The goal of any career is to become the best. People should not be in a hurry to succeed, but nor should they give up halfway," he said.

When Xu first began teaching chemistry, there was no syllabus, nor were there any suitable reference books or textbooks. He had to formulate a teaching plan from scratch.

"I needed to understand the subject first in order to teach my students to understand it. I also gave them the space to think about things for themselves, and then answered their questions," he said, explaining the teaching method he developed.

Xu believes that the future of science is interdisciplinary, and that scientists must develop a deeper understanding of other specialties. He practices that belief, which is why once, while overseeing a postgraduate's thesis, when he realized the student could benefit from statistic classes, he enrolled him in the mathematics department to help him finish the paper.

Xu believes research is just as important as teaching.

"It's only through research that teachers can improve their ability to perceive and solve problems. Teachers need to understand the developing trends in a subject, and broaden their thinking methods so that they can better guide students," he said.

Thanks to their professor's integrated attitude toward teaching and research, Xu's students have made notable contributions to the field, and three have been elected to the Chinese Academy of Sciences.

In 1991, he finished writing Inorganic Synthetic Chemistry, the first textbook of its kind in China and over the past two decades, he and his team have focused on books. Like many people his age, he is not used to computers, and prefers to write by hand.

While his greatest wish is to pass on the teaching experience and scientific knowledge gained over the course of a lifetime to future generations, Xu also hopes that young people will develop their own ways of thinking and working, and not just follow old models. "Sometimes, the traditional ways don't help much with new practices," he said.

Xu himself continues to explore. Most recently, he has been researching condensed matter physics and chemistry with other scholars.

"I still hope to make more contributions to the development of chemistry research and teaching," he said.

Han Junhong contributed to this story.