Hu Zheng, Professor of the Key Laboratory of mesoscopic chemistry of Ministry of education, recently published a special review paper Carbon based metal free ORR electronics for fuel cells: past, present and future in Advanced Materials (advanced. Material. 31, 2019, 1804799). This paper systematically discussed the past, present and future of the research field of carbon based metal free oxygen reduction electrocatalysts. Associate Professor Yang Lijun is the first author of the review paper.
With the mass production of fuel cell powered vehicles from Toyota and other traditional vehicle enterprises, fuel cell also ushered in a new wave of rapid development. Reducing the consumption of platinum catalyst in fuel cell stack and lowering the cost is becoming urgent. In 2009, professor Liming Dai of Case Western Reserve University, reported in Science that nitrogen doped carbon nanotube array catalyst possesses better oxygen reduction reaction (ORR) performance than platinum in alkaline medium, and this activated the research field of carbon based metal free ORR electrocatalysts. Professor Hu Zheng's research group entered this filed at very early time since they have been carrying out research work in carbon based nanomaterials for many years. They found that, similar to the electron-rich nitrogen doping, the electron-deficient boron doping can also turn the inactive sp2 carbon into the metal free catalyst for ORR. Therefore, they proposed that the activity of carbon based metal free ORR electrocatalysts should originate from the activation of carbon π electron, and verified it by designing and regulating the doping configuration and structure-activity relationship of boron nitrogen co-doped carbon nanotubes. On this basis, it is further proposed that the intrinsic defects of carbon may also induce the activity of ORR, which is confirmed by the high ORR activity of the pure carbon nanocages with rich defects. The contribution of the intrinsic defects expand the research of carbon based metal free ORR electrocatalysts from the doped carbon material to the defective carbon material, and now it has been actively studied. In order to promote the research to a more challenging acid medium, they designed and developed a sulfur nitrogen co-doped carbon tube with a record high onset potential. Recently, they worked with Zhou Zhiyou of Xiamen University and systematically discussed the in-situ formation process and activity generation mechanism of ORR active structure in N-doped graphene in acid medium. A series of related works have been published in: Angew. Chem. Int. ed. 50 (2011) 7132; Adv. Mat. 24 (2012) 5593; JACS 135 (2013) 1201; Chinese J. catalyst. 34 (2013) 1986; ACS catalyst. 5 (2015) 6707; Chem. EUR. J. 22 (2016) 10326; ACS Energy lett. 3 (2018) 986; Acc. Chem. Res. 50 (2017) 435 and other journals, which have important academic influence and are widely cited by Science, Nature and other journals. Four of them are highly cited papers. This review focuses on the important progress, research status and development trend in the past five years, which will play a very positive role in promoting the development of this field.
This series of research has been supported by NSFC key projects, general projects, and National Key Research and Development Program of the Ministry of science and technology.
