Graphitized Biochar Derived from Agricultural Wastes Enhances Methanogenesis via Conductivity‐Driven Direct Interspecies Electron Transfer
Biochar has emerged as a promising conductor for facilitating direct interspecies electron transfer (DIET) in anaerobic digestion (AD), yet the mechanisms linking its structural features to methanogenic performance remain unclear. Here, how feedstock type and pyrolysis conditions modulate biochar conductivity and consequently shape methanogenic pathways is investigated. Using straw, wood, and nutshell-derived biochars, nutshell biochar pyrolyzed at 550 °C(CC550) is demonstrated to achieve the highest methane yield, enhancing production by 59% compared to the control and outperforming straw and wood-based biochars by 12% and 5% respectively. Graphitization analysis confirms that high electrical conductivity is key to accelerating methanogenesis. Metagenomic profiling reveals that CC550 enriches cellulose-degrading bacteria and DIET-associated taxa, while upregulating genes related to pili and cytochrome c expression, promoting acetoclastic methanogenesis through enhanced electron flow. These findings highlight the role of graphitic biochar as a metabolic modulator in AD and offer insights for engineering carbon materials to optimize bioenergy recovery from organic waste.
Authors
- Dejin Gu
- Hongyi Lyu
- Caiyun Yang (ORCID: https://orcid.org/0000-0002-0521-4230)
- Tongji Xie (ORCID: https://orcid.org/0000-0002-3276-9645)
- Yuxin Qiu (ORCID: https://orcid.org/0009-0005-5938-9545)
- Heyu Chen
- Yiqing Yao (ORCID: https://orcid.org/0000-0002-4692-8977)
- Weiguo Liu (ORCID: https://orcid.org/0000-0001-8176-2522)
- Siying He
- Shuai Zhang (ORCID: https://orcid.org/0000-0001-9723-9832)
- Heng Wu (ORCID: https://orcid.org/0000-0001-6544-310X)
- Zhen Liu (ORCID: https://orcid.org/0000-0002-2445-9962)
- Xiaohui Guo (ORCID: https://orcid.org/0000-0002-5588-0995)
- Yirong Wang (ORCID: https://orcid.org/0000-0003-3750-183X)
- Xuanmin Yang (ORCID: https://orcid.org/0009-0009-8525-9946)
- Mengyi Wang (ORCID: https://orcid.org/0000-0002-9348-6876)
- Xinke Zhang (ORCID: https://orcid.org/0000-0002-3527-2140)
- Jinzhi Huang
- Jia Liu (ORCID: https://orcid.org/0000-0002-7708-4666)
Institutions
- Harbin Institute of Technology (CN)
- North West Agriculture and Forestry University (CN)
- City University of Hong Kong, Shenzhen Research Institute (CN)
- Qinhuangdao Glass Industry Research and Design Institute (China) (CN)
- Shaanxi Normal University (CN)
- Northwest A&F University (CN)
Publication Details
- Journal
- Advanced Science
- Published
- 2025-08-04
- DOI
- https://doi.org/10.1002/advs.202508739
- Citations
- 2
- Primary Topic
- Microbial Fuel Cells and Bioremediation
- Type
- article
- Field-Weighted Citation Impact
- 1.60
Funders
- Chinese Universities Scientific Fund
- National Key Research and Development Program of China