Table 2.

Photocurrent densities of ternary heterostructures.

Photocatalytic Material	Methods	Morphology	Electrolyte	Potential	Irradiation	Photocurrent Density	Ref
WO3–Pt–CdS	Combination of wet-chemical, photodeposition and hydrothermal techniques	Hollow microspheres composed of small crystallites	0.5 M Na2SO4	0.5 V vs. Ag/AgCl (1.82 V vs. RHE)	Vis light	0.16 μA/cm2	[192]
SnO2/WO3/BiVO4	Combination of electron beam deposition and metal organic decomposition technique	Planar film	0.5-M Na2SO3	1.23 vs. RHE	100 mW/cm2	2.01 mA/cm2	[193]
WO3/C3N 4//CoOx	Combination of a hydrothermal method with wet impregnation	film		1.23 V vs. Ag/AgCl (1.8 V vs. RHE)	100 mW/cm2	5.76 mA/cm2	[170]
CuWO4−WO3	electrodeposition	film	0.1-M KH2PO4	0.618 V vs. Ag/AgCl (1.23 vs. RHE)	100 mW/cm2	0.3 mA/cm2	[194]
WO3/(Er, W):BiVO4	spray coating	monoclinic clinobisvanite structure	0.1-M K2HPO4	1.23 V vs. RHE	100 mW/cm2	4.1 ± 0.19 mA cm−2	[195]
WO3/(Er, W):BiVO4	spray coating	monoclinic clinobisvanite structure	0.1-M K2HPO4	2.3 V vs. RHE	100 mW/cm2	7.2 ± 0.39 mA cm−2	[195]
TiO2/WO3/BiVO4	hydrothermal	brochosomes-like	0.5-M Na2SO4	0.35 V vs. RHE	100 mW/cm2	3.13 mA cm−2	[196]
WO3/ Fe2O3/Co(OH)	electrospray deposition	worm-like nanobars	0.1-M NaOH	1.23 vs. RHE		0.62 mA cm−2	[197]
Ag-functionalized CuWO4/WO3	electrophoretic deposition	thin film	potassium phosphate buffer solution	0.62 V vs. Ag/AgCl (1.23 V vs. RHE)		0.205 mA cm−2	[198]
CuWO4/BiVO4 with Co-Pi	drop-casting and thermal annealing method	nanoflakes	1.0 M of Na2SO4 with 0.1 M of sodium phosphate buffer (pH = 7)	1.23 V vs. RHE	100 mW/cm2	2.25 mA cm−2	[199]
BiVO4/WO3/SnO2 connected with perovskite solar cell tandem device	Spin-coating	triple-layer planar film	pH 7 phosphate buffer electrolyte	1.23 V vs. RHE	100 mW/cm2	3.1 mA/cm2	[26]
ZnWO4/WO3	Piezo-dispensing	Spot Arrays	0.1-M Na2SO4 at pH 7	0.7 V vs. Ag/AgCl (1.31 V vs. RHE)		0.75 mA/cm2	[200]
b-Cu2V2O7/WO3	Seeded-growth approach		0.1-M sodium borate buffer (pH 8.2) containing 0.1-M Na2SO3	1.23 V vs. RHE	100 mW/cm2	0.45 mA cm−2	[201]
CaMn2O4/WO3	Spin-coating	Thin film	0.5-M Na2SO4 solution (pH 6)	1.09 V vs. RHE		1.5 × 10−3 mA cm−2	[202]
Pt/WO3/Ag	Hydrothermal method, chemical bath, photoassisted electrodeposition	Nanorods			100 mW/cm2	1.13 mA/cm2	[153]
WO3/CdS/NiOOH	hydrothermal method, successive ionic layer adsorption and reaction, photo-assisted electrodeposition	Nanorods	d 0.2-M Na2SO4-0.1-M Na2SO3	1.23 V vs. RHE		1.5–2 mA/cm2	[203]
ZnWO4/WO3	hydrothermal	Nanorods	0.5 M Na2SO4	1.23 V vs. RHE	100 mW/cm2	1.87 mA cm−2	[204]
WO3/BiVO4/ZnO	drop-casting method, atomic layer deposition	Nanosheets	0.5-M Na2SO4	1.23 V vs. RHE	100 mW/cm2	2.5–3.00 mA cm−2	[205]
Au-surface/BiVO4/WO3/Au-bottom	hydrothermal, sol–gel spin-coated,	Nanospheres	0.5 M Na2SO4	1.23 V vs. RHE		1.31 mA/cm2	[63]
WO3/C@CoO	hydrothermal process and immersion method	Octopus tentacles-like	1.0-M KOH	55 mV (vs. RHE)		10 mA cm−2	[206]
WO3@ZnWO4@ZnO	layer deposition technique and hydrothermal process	nanosheets	mixed aqueous solution of 0.35-M Na2S and 0.25-M NaSO3 (pH = 13.4)	1.23 V vs. RHE	100 mW/cm2	~1.57 mA/cm2	[207]
WO3/rGO/Sb2S3	chemical bath deposition	nanoplates	0.5-M Na2SO4 (pH~7)	1.23 V vs. RHE		1.20 mA/cm2	[208]
Cu2O/CuO/WO3	Electrodeposition, spin-coating	Thin film		0 V vs. RHE		−1.9 mA/cm2	[209]
WO3/BiVO4/Co-Pi	Electrodeposition	composite inverse opals	0.5-M Na2SO4	1.4 V versus Ag/AgCl (0.67 V vs. RHE)	100 mW cm−2	4.5 mA cm−2	[210]
WO3/BiVO4/TiO2	Spin-coating, wet chemistry	platelike	0.1-M Na2SO4	1.23 V vs. RHE	100 mW/cm2	~3.9 mA/cm2	[211]
TiO2/WO3/Pt	Electrospinning technique	fibers	0.2-M Na2SO4			15–20×10−3 mA/cm2	[212]
TiO2-TiCl4-WO3	Hydrothermal method + Electrodeposition	nanorods	KOH	1.23 V vs NHE	100 mW/cm2	3.86 mW/cm2	[213]