Effect of Nitrogen-Doped Carbon Dots (NCDs) on the Characteristics of NCD/MIL-53(Fe) Composite and Its Photocatalytic Performance for Methylene Blue Degradation under Visible Light

Table 1

Synthesis strategy, physical properties, and performance of some MOF-based composites.

Note	Materials	Preparation strategies	Application	(m^2 g^-1)	Highlighted results	Ref
1	ZIF-8	Hydrothermal	Bisphenol A absorption	206	BPA adsorption capacity reached 59.2 mg g^-1	[35]
	ZIF-8@SBA-15	Step-by-step coordination method		722	BPA adsorption capacity up to 116.9 mg g^-1
2	ZIF-67	Hydrothermal	Cr (VI) reduction	1300.2	Cr(VI) could not be reduced into Cr(III)	[36]
	Pd@ZIF-67	MOF encapsulated Pd nanoparticles		69.3	Cr(VI) (initial concentration: 2.0 mM) was converted the to Cr(III) within 5 min
3	MIL-53(Fe)	Solvothermal	Photodegradation Methylene Blue	47.9	FM-1 had rate constant which is two times that of MIL-53(Fe) in UV light	[37]
	Fe2O3/MIL-53(Fe)	Thermal decomposition of MIL-53(Fe)	Photodegradation Methylene Blue	47.4
4	Fe3O4@MIL-100(Fe)	Core-shell microsphere	Photodegradation Methylene Blue	511.42	The photodegradation efficiency reached 99.77% in 200 min under visible light and with H2O2 support	[38]
5	Fe-BTC/polydopamine	PDA pinned on the internal MOF surface	Heavy metal ions absorption	—	Binds up to 1634 mg of Hg^2+ and 394 mg of Pb^2+ per gram of composite	[39]
6	MIL-53(Al)/PVA	Blended MOF into PVA	Water desalination	—	Desalinate 100 g L^-1 NaCl solution for over 120 hours of continuous operation, with a salt rejection rate of over 99.999%	[40]
7	MIL-53(Fe)	Solvothermal	Cr (VI) reduction	20.6	The pseudofirst order reaction kinetics () of Cr(VI) removal over the CMFe-3 is 0.0191, which is 3.4 times higher than pure MIL-53(Fe) ()	[41]
	g-C3N4/MIL-53(Fe)	In situ solvothermal method		18.5
MOF-carbon composite
8	CQDs/MIL-53(Fe)	CQD-embedded MIL-53(Fe) by in situ synthesis	Cr (VI) reduction	—	Cr(VI) (initial concentration: 8 mg L^-1) was converted to Cr(III) within 50 min under visible light	[11]
9	CQDs@ZIF-5	Core-shell	Photodegradation Methylene Blue	—	MB (initial concentration: 25 mg L^-1) was decomposed within 100 min under visible light	[12]
10	MIL-88(Fe)	Solvothermal method	Photodegradation Methylene Blue and rhodamine B	—	MIL-88(Fe)@GO composites had MB and RB degradation efficiency within 50 and 60 min, respectively	[9]
	MIL-88(Fe)/GO	In situ synthesis		—	MIL-88(Fe)@GO composites had MB and RB degradation efficiency within 20 and 30 min, respectively
11	HKUST-1/GO/Fe3O4	In situ synthesis	MB absorption	533	Maximum absorption capacity 105.88 mg g^-1 at 25°C	[8]
12	NCDs/MIL-53(Fe)	In situ synthesis	Photodegradation Methylene Blue	6.99	NCDs/MIL-53(Fe) had MB degradation efficiency within 60 minutes under visible light irradiation (MB concentration; 10 mg L^-1); NCDs/MIL-53(Fe) can be reused for 5 times	This study