Efficient Photoelectron Capture by Ni Decoration in Methanosarcina barkeri-CdS Biohybrids for Enhanced Photocatalytic CO2-to-CH4 Conversion

Jie Ye; Guoping Ren; Li Kang; Yiyun Zhang; Xing Liu; Shungui Zhou; Zhen He

doi:10.1016/j.isci.2020.101287

Efficient Photoelectron Capture by Ni Decoration in Methanosarcina barkeri-CdS Biohybrids for Enhanced Photocatalytic CO₂-to-CH₄ Conversion

iScience. 2020 Jul 24;23(7):101287. doi: 10.1016/j.isci.2020.101287. Epub 2020 Jun 20.

Authors

Jie Ye¹, Guoping Ren¹, Li Kang¹, Yiyun Zhang¹, Xing Liu¹, Shungui Zhou², Zhen He³

Affiliations

¹ Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
² Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China. Electronic address: sgzhou@soil.gd.cn.
³ Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA.

Abstract

Semi-artificial photosynthesis (biohybrid) provides an intriguing opportunity for efficient CO₂-to-CH₄ conversion. However, creating a desirable semiconductor in biohybrids remains a great challenge. Here, by doping Ni into CdS nanoparticles, we have successfully developed the Methanosarcina barkeri-Ni:CdS biohybrids. The CH₄ yield by the M. barkeri-Ni_(0.75%):CdS biohybrids was approximately 250% higher than that by the M. barkeri-CdS biohybrids. The suitable Ni dopants serve as an effective electron sink, which accelerates the photoelectron transfer in biohybrids. In addition, Ni doping changes the metabolic status of M. barkeri and results in a higher expression of a series of proteins for electron transfer, energy conversion, and CO₂ fixation. These increased proteins can promote the photoelectron capture by M. barkeri and injection into cells, which trigger a higher intracellular reduction potential to drive the reduction of CO₂ to CH₄. Our discovery will offer a promising strategy for the optimization of biohybrids in the solar-to-chemical conversion.

Keywords: Biochemistry; Energy Resources; Nanoparticles.