Doping of TiO₂ Polymorphs for Altered Optical and Photocatalytic Properties

Table 1

Crystalline lattice parameters, bulk modulus (B), and band gap 𝐸_g of TiO₂ polymorphs. HF: Hartree-Fock, PBE [18], BLYP [19, 20], B3LYP [21, 22], OLCAO: Orthogonalized Linear Combination of Atomic Orbitals, FLAPW: full potential linearized augmented plane wave method.

	a (Å)	b (Å)	c (Å)	B (GPa)	𝐸g (eV)	Notes	Ref.
Rutile P42/mnm	4.634	—	2.963	204	—	PBE	[23]
	4.546	—	2.925	249	—	LDA	[23]
	4.679	—	2.985	200	—	BLYP	[23]
	4.58666	—	2.95407	—	—	neutron	[24]
	4.5929	—	2.9591	—	—	X-ray	[25]
				209.34	1.78	OLCAO	[26]
	4.568	—	2.926	—	1.68	LDA	[27]
	4.579	—	2.989	—	—	HF	[28]
	4.548	—	2.944	—	—	LDA	[28]
	4.623	—	2.987	—	—	GGA	[28]
	4.567	—	2.932	—	2.00	LDA	[10]
	4.594	—	2.959	—	1.9	GGA	[29]
	4.653	—	2.965	240	2.0	LDA	[30]
	4.5729	—	2.9511	206	3.05	OL-LDA	[31]
	—	—	—	—	3.24	B3LYP	[32]
	—		—	—	2.0	LDA	[33]
	—	—	—	210	—	—	[34]
	—	—	—	—	3.0	—	[35]
	—	—	—	—	3.07	13% HF	[36]
	—	—	—	—	—	—
Anatase I41/amd	3.786	—	9.737	176	—	PBE	[23]
	3.735	—	9.534	199	—	LDA	[23]
	3.828	—	9.781	178	—	BLYP	[23]
	3.78216	—	9.50226	—	—	neutron	[24]
	3.692	—	9.851	—	2.00	FLAPW	[33]
	3.783	—	9.514	—	—	X-ray	[25]
				272.11	2.04	OLCAO	[26]
	—	—	—	200.2		B3LYP	[32]
	—	—	—	—	3.26	LO-LDA	[37]
		—	—	179	—	—	[38]
	—	—	—	—	3.34	—	[39]
	—	—	—	—	3.58	13% HF	[36]
		—	—	—
Brookite Pbca	9.184	5.447	5.145	—		X-ray	[40]
				137.32	2.2	OLCAO	[26]
	9.276	5.502	5.197	220	3.78	B3LYP	[32]
	—	—	—	255	—	—	[41]
	—	—	—	—	3.4	—	[39]