Bioreduction of Precious Metals by Microorganism: Efficient Gold@N-Doped Carbon Electrocatalysts for the Hydrogen Evolution Reaction

• Published in: Angewandte Chemie International Edition 2016-07, Vol.55 (29), p.8416-8420
• Main Authors: Zhou, Weijia, Xiong, Tanli, Shi, Chaohong, Zhou, Jian, Zhou, Kai, Zhu, Nengwu, Li, Ligui, Tang, Zhenghua, Chen, Shaowei
• Format: Article
• Language: English
• Subjects: Benign; biosynthesis; Carbon; Catalysis; catalyst recycling; Catalytic activity; Charge transport; core-shell structure; Electrocatalysts; electron transfer; Electronic waste; Evolution; Fabrication; Gold; Heavy metals; HER protein; Hydrogen; hydrogen evolution reaction; Hydrogen evolution reactions; Metals; Methanol; Nanoparticles; Noble metals; Oxygen; Oxygen reduction reactions; Recovery; Robustness; Slope stability
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201602627

The uptake of precious metals from electronic waste is of environmental significance and potential commercial value. A facile bioreductive synthesis is described for Au nanoparticles (ca. 20 nm) supported on N‐doped carbon (Au@NC), which was derived from Au/Pycnoporus sanguineus cells. The interface and charge transport between Au and N‐doped carbon were confirmed by HRTEM and XPS. Au@NC was employed as an electrocatalyst for the hydrogen evolution reaction (HER), exhibiting a small onset potential of −54.1 mV (vs. RHE), a Tafel slope of 76.8 mV dec−1, as well as robust stability in acidic medium. Au@NC is a multifunctional electrocatalyst, which demonstrates high catalytic activity in the oxygen reduction reaction (ORR), as evidenced by an onset potential of +0.97 V, excellent tolerance toward methanol, and long‐term stability. This work exemplifies dual recovery of precious Au and fabrication of multifunctional electrocatalysts in an environmentally benign and application‐oriented manner. Rags to riches: Gold nanoparticles supported on N‐doped carbon (Au@NC) derived from the bioreduction of gold ions by Pycnoporus sanguineus cells are active HER electrocatalysts with a small onset potential of −54.1 mV and a Tafel slope of 76.8 mV dec−1. The catalyst is a stable and eco‐friendly candidate for energy applications. Key: a) bioreduction by Au@microorganism, b) calcination, c) catalysis.