Table 1.

Studies Reporting Stimulating Anaerobic Digestion to Methane with Conductive Materials

Conductive Materiala	Organic Substrate	Types of Digestersb and Controlsc
Granular activated carbon	Acetate	AnSBR (Zhang et al., 2017bc; Zhu et al., 2019c; Park et al., 2018), CSTR (Lei et al., 2016)
	Ethanol	AnSBR (Park et al., 2018; Lin et al., 2017)
	Propionate	AnSBR (Xu et al., 2018; Guo et al., 2020; Zhao et al., 2016b)
	Butyrate	AnSBR (Xu et al., 2018; Zhao et al., 2016b)
	Benzoate	AnSBR (Zhang et al., 2020a)
	Glucose	AnSBR (Yang et al., 2017), UASB (Zhang et al., 2020b; Guo et al., 2020)
	Dairy waste	AnSBR (Zhao et al., 2017ac)
	Bagasse waste	AnSBR (Zhao and Zhang, 2019c)
	Dog food	AnSBR (Dang et al., 2016c; Dang et al., 2017c)
	Kitchen waste	AnSBR (Zhang et al., 2017a, 2018a; Capson-Tojo et al., 2018)
	Waste activated sludge	AnSBR (Yan et al., 2020; Yang et al., 2017; Sun et al., 2020)
Carbon cloth	Butanol	AnSBR (Zhao et al., 2017cc)
	Leachate	UASB (Lei et al., 2016)
	Dog food	AnSBR (Dang et al., 2016c; Dang et al., 2017c)
Biochar	Sucrose	UASB (Wang et al., 2018a)
	Phenol	AnSBR (Wang et al., 2020c)
	Citrus peel waste	AnSBR (Fagbohungbe et al., 2016)
	N-rich substrate	AnSBR (Mumme et al., 2014c)
Carbon nanotube	Acetate	AnSBR (Shen et al., 2020)
	Benzoate	AnSBR (Zhang et al., 2020a)
	Oleic acid	AnSBR (Mostafa et al., 2020)
Graphene	Ethanol	AnSBR (Lin et al., 2017)
	Glucose	AnSBR (Tian et al., 2017), UASB (Tian et al., 2017)
Magnetite	Acetate	AnSBR (Wang et al., 2020bc; Zhuang et al., 2018); UASB (Chen et al., 2020)
	Propionate	AnSBR (Guo et al., 2020; Yamada et al., 2015; Jing et al., 2017; Cruz et al., 2014)
	Glycerol	AnSBR (Im et al., 2019), Electrochemically Assisted Digester (Im et al., 2019)
	Oleic acid	AnSBR (Mostafa et al., 2020)
	Sucrose	EGSB (Wang et al., 2019b)
	Leachate	UASB (Lei et al., 2018)
	Whey	AnSBR (Baek et al., 2015)
	Tryptone	AnSBR (Yin et al., 2017a, 2018)

^aMore detailed expanded table is available as Table S1.

^bAbbreviations: AnSBR, anaerobic sequencing batch reactor; CSTR, continuous stirred tank reactor; UASB, up-flow anaerobic sludge blanket; EGSB, expanded granular sludge blanket.

^cDesignates control studies with non-conductive materials were conducted.