Table 1. Comparison of Physical Properties and Absorption Capacity of Varied Superabsorbent Aerogel^a.

category	absorbent materials	density (mg/cm3)	absorption capacity (g/g)	normalized maximum absorption capacity (mL/g)	refs
natural polymers	electrospun cellulose	1.1–7.0	201–373	250	this study
	chitin	21.2–24.3	29–58	39	(49)
	bacterial cellulose	6.69–6.77	86–185	124	(52)
	ethyl cellulose	18.9	32–64	43	(50)
	cellulose esters	4.3–110	112	140 normalized by kerosene oil	(53)
	gelatin	7.2	70–123	83	(51)
	microfibrillated cellulose	2.4–24.2	88–228	235 normalized by silicone oil	(36)
	cellulose nanofibrils	1.7–8.1	210–375	251	(22)
synthetic polymers	polyethylenimine	N/A	29–39	26	(69)
	carbonized lignin-coated melamine foam	6.4	98–217	146	(54)
	graphene-coated melamine foam	N/A	50–130	87	(55)
	PDVB-PDMS-coated melamine	N/A	38–123	82	(56)
	poly(vinyl alcohol)/carbon nanotube	27–83	10–52	35	(57)
	poly(vinyl alcohol)/graphene	3.3	130–274	184	(58)
	poly(vinyl alcohol)/cellulose nanofibrils	13.0	44–96	64	(35)
	polystyrene/carbon nanotubes	N/A	100–270	181	(59)
carbonized natural polymers	carbonized glucose nanofibers	3.3	40–115	72 normalized by phenoxin	(8)
	carbonized bacterial cellulose	4–6	106–312	208 normalized by phenoxin	(60)
	carbonized cotton	12	50–192	80	(61)
	carbonized poplar catkins	4.3	80–161	107	(62)
	carbonized waste paper	23.6	33–70	44 normalized by phenoxin	(63)
	carbonized kapok fibers	1	147–292	183 normalized by phenoxin	(64)
graphitic carbon	graphene aerogel	3.5	134–283	189	(66)
	carbon nanotubes	5–10	80–180	120	(65)
	graphene oxide/carbon nanotubes	0.16–7.6	215–913	570 normalized by phenoxin	(7)
	graphene framework	2.1	200–600	375 normalized by phenoxin	(67)
	reduced graphene oxide/bacterial cellulose carbon fiber	0.7–10.2	393–1002	626 normalized by phenoxin	(68)

^aNote: unless specified, the normalized maximum absorption capacity was based on chloroform.