Table 2.

The strategy for improving the QY of CDs

	Materials	QY (%)	Mechanism	References
Doping	Urea and thiourea	78	Electron transition from the ground state to the lowest excited singlet state	74
	NH3 and boric acid	43.2		78
	Si	97.32		80
	Cr	20		81
	Phosphoric and hydrochloric acids	15		82
	Zn	32.3		83
	Boric acid	25		84
	Se	52		85
Hydrogen bonding	Ethanol solution	50.3	The stabilization of the excited state for more efficient radiative recombination	86
	PVA solution	47		87
High crystalline state	Catechol	32	Reduces the non-radiative electron-hole recombination center	89
	Ethanol	38.7		90
Heteroatom-precursor	CA	53		91
	FA	94.5		92
	Ethylenediamine	73		93
	L-cysteine	78		97
	PEI	54		95
	β-alanine	14		96
	1,2,4-triaminobenzene	50.3		97
	Diethylenetriamine	27.7		98
	Ethanolamine	21.85		99
	Ammonium citrate	67		100