Table 2. Dopant ions and their respective precursors for the synthesis of ZnO nanoparticles by wet chemical methods.

Dopant Element	Dopant Precursors	Doping Level	Solvent	Particles Dimensions	Ref.
La	LaCl3·7H2O	5% mol	H2O a	123 nm 1	[116]
Ce	CeCl3·7H2O	1% mol	H2O a	20–30 nm 1	[171]
	Ce(NO3)2·6H2O	0.1–5% mol	H2O b	70–85 nm 1	[112]
Nd	Nd(NO3)3·6H2O	5% mol	H2O a	101 nm 1	[172]
Sm	Sm(NO3)3 ·6H2O	1–4% mol	H2O a	35 nm 1	[193]
Eu	EuCl3·6H2O	5% mol	H2O a	79 nm 1	[150]
	Eu(NO3)3·5H2O	5% mol	CH3OH a	9 nm 2	[164]
Gd	Gd(NO3)3·6H2O	5% mol	CH3OH a	9 nm 2
	Gd(CH3CO2)3	2–30% mol	CH3CH2OH	4 nm2,3	[163]
V	NH4VO3	1% mol	H2O a	47 nm 2	[194]
Mn	Mn(NO3)2	0.5–3% mol	CH3CH2OH	50–120 nm 2	[183]
	MnCl2 ·4H2O	1–5% mol	CH3OH	100 nm 2	[126]
Fe	Fe(SO4)·7H2O	3–7% mol	H2O a	15–35 nm 2	[195]
	FeCl3	1–10% mol	H2O a	9–15 nm 2	[162]
	Fe(NO3)3	2–6% mol	H2O a	~250 nm 4	[196]
Co	Fe(NO3)2 ·6H2O	1–10% mol	H2O	25–50 nm 2	[184]
	CoCl2	5–10% mol	H2O a	Various morphologies	[175]
Ni	NiCl2·6H2O	3% mol	CH3CH2OH a	25–40 nm 1	[159]
Cu	CuCl2·2H2O	0.5–30 at.%	H2O b	~250 nm 4	[176]
Ag	AgNO3	5% mol	H2O a	80 nm × 350 nm 5	[152]
Li	Li(CH3CO2)3·2H2O	3-5 at.%	TREG (C6H14O4)	~250 nm 4	[144]
Mg	Mg(NO3)2·6H2O	5% mol	H2O a	62 nm	[166]
Al	Al(NO3)3·9H2O	15% mol	H2O a	~60 nm 1	[187]

^aNaOH as base

^bNH₄OH as base

¹Rod’s mean diameter.

²Spherical particles’ diameters.

³TMAH (tetramethylammonium hydroxide) and oleic acid were also added in the synthesis procedure.

⁴The dimensions have been estimated by electron microscopy images.

⁵Nanoplates’ thicknesses and diameters.