Gd	Gadolinium
TiO2	Titanium Dioxide
CPTi	Commercial Pure Titanium
GdTNTAs	Gd-doped TiO2 Nanotube Arrays
XRD	X-ray Diffraction
FE-SEM	Field-Emission Scanning Electron Microscopy
EDS	Energy-Dispersive X-ray Spectroscopy
XPS	X-ray Photoelectron Spectroscopy
UV-Vis	Ultraviolet-Visible Spectrophotometry
MB	Methylene Blue
TA	Terephthalic Acid
IPA	Isopropanol
EDTA-2Na	Disodium Ethylenediaminetetraacetate
NIR	Near-Infrared
BQ	Benzoquinone
Cₜ/C0	Time-Normalized Concentration
VB	Valence Band
CB	Conduction Band
e−	Electron
h+	Hole
·OH	Hydroxyl Radical
·O2−	Superoxide Radical Anion
·HO2	Hydroperoxyl Radical
H2O2	Hydrogen Peroxide
CO2	Carbon Dioxide
DI	Deionized
EG	Ethylene Glycol
NH4F	Ammonium Fluoride
GGA+U	Generalized Gradient Approximation plus Hubbard U
DOS	Density of States
Eg	Bandgap Energy