Constantin Holzer, a young PhD candidate with Renmin University of China, never fails to amaze his Chinese students with his proficiency in six languages, especially Chinese.

A 27-year-old student with a focus on low-carbon economy, Holzer obtained a master's degree at Peking University in 2009 and finished a training program at the Diplomatic Academy of Vienna in 2010.

"Two prominent scholars from Austria and China led my way into China research and green economy studies," Holzer said on Monday.

Professor Susanne Weigelin-Schwiedrzik, vice-rector of the University of Vienna and a researcher of Sinology, became his tutor in his undergraduate years.

Later, his friendship with Professor Yang Zhi, a researcher of international development studies at Renmin University of China, evolved into a partnership in research based in China.

Despite his one-year study in the Diplomatic Academy of Vienna - a leading college cultivating diplomats-to-be for Austria - Holzer decided to return to China in 2010 and embarked on one year of work as a teacher and researcher at the Suzhou Research Institute of Renmin University of China's International College.

Low carbon is now among the hottest issues on the global political and economic agenda, and Holzer said green economy shows huge potential for sustainable development in both China and Europe.

"This made me decide to stay here for studies based in China," said Holzer.

Some European countries are still lagging behind China's environmental campaign on banning free plastic bags in shopping malls, said Holzer.

"China and Europe may draw more lessons from each other."

Austria started earlier than China in research and development of low carbon technologies such as sewage treatment and bio-gas, and Austria's nationwide orientation on energy saving intended for domestic public may also inspire Chinese policymakers.

Sharing technological ideas between China and Austria helps achieve a win-win situation and boost bilateral business, said Holzer, adding that China is a huge country with talent and remarkable potential in updating energy-saving technologies.

Youths from both countries can promote energy saving on social networks to boost communication in an increasingly globalized world, said Holzer.

China-Austria public diplomacy is now showing "green" signs in diversified cooperation and exchanges of talent, experts said.

The China Scholarship Council funded 10 Austrian post-grads this year and Holzer was among the two selected PhD candidates to pursue further studies in China.

"Five years ago, most of them came to China simply for language study," Chen Hangzhu, an education official with Chinese embassy in Austria, said, adding that Austrian post-grads are paying more attention to studies in international relations, trade as well as philosophy.

Meanwhile, both China and Austria are diversifying links to connect Austrian people to China's culture, including the Chinese language.

"My proficiency in Mandarin and my love for China can be traced back to my maiden voyage to China in 2004, which impressed me most," said Holzer, who in addition to Chinese speaks English, French, Spanish, Russian and, of course, his native German.

He joined an overseas voluntary program organized by Austrian government to teach kids in a SOS school for 14 months in Qiqihar, a Northeast China city, which granted him sufficient exposure to the Chinese language.