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

Abstract

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.

RuP2‐Based Catalysts with Platinum‐like Activity and Higher Durability for the Hydrogen Evolution Reaction at All pH Values

“…[6] To solve such problems,earth-abundant non-Pt catalysts (Mo-, W-,Fe-, Co-, Ni-, and Cu-based materials) have been intensively studied. [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26] Nevertheless,t heir catalytic performance is still far from satisfactory in comparison with Pt, and most of them only show their best activity in acidic media. Considering the inevitable proton concentration change during the HER process,a ni deal electrocatalyst is expected to work well in different pH solutions so that the water splitting process can be more energy-efficient.…”

Environmental Catalysis: Present and Future

“…Microbial synthesis is also a useful strategy to valorize precious metal such as Au and Ag from waste electronic equipements (e. g. mobile phones) by an economically viable and eco‐friendly perspective. In this direction, the biological synthesis of gold nanoparticles and gold@carbon core‐shells structures have been successfully accomplished by R. oryzae cells and Pycnoporus sanguineus cells, respectively. The synthesized Au@carbon nanostructures (Figure C) showed excellent electrocatalytic performances for the ORR and HER reactions indicating that they can be employed as efficient multifunctional electrocatalytic platforms.…”

“…Copyright, 2016 American Chemical Society. Reproduced with permission of ref . Copyright, 2016 Willey.…”

Shewanella oneidensis Assisted Biosynthesis of Pd/Reductive‐Graphene‐Oxide Nanocomposites for Oxygen Reduction Reaction

“…Over the past decades, there has been an increased emphasis on the topic of “green” nanotechnology for the synthesis and fabrication of metal nanoparticles . Bio‐mediated synthesis using microbes is an environment‐friendly “green” approach and has become as a promising substitute to the traditional chemical methods for nanoparticles synthesis . It provides a nontoxic, inexpensive and reliable way for nanoparticles synthesis with diversity in size, shape, composition and physicochemical properties, and the synthesis can be easily scaled up to high level.…”