Table 2 Summary of some adsorbent-based carbon quantum dots used for Cd(II) removal

SnO₂ quantum dots decorated reduced graphene oxide

pH = 6.5, 30 °C

[71]

Carbon quantum dots/layered double hydroxide

pH = 6, T = 30 °C

[9]

Carbon dots modified mesoporous organosilica

pH = 8, T = 30 °C

[72]

Poly (acrylic acid)-activated carbon nanocomposite

pH = 6, T = 25 °C

[73]

Hollow calcite single crystals with carbon quantum dots

pH = 5, T = 25 °C

[74]

S,N codoped carbon quantum dots modified chitosan membranes

pH = 8

T = 25 °C

UV = 365 nm

This work