. 2023 Oct 30;5(24):6944–6957. doi: 10.1039/d3na00776f

Comparison of the cold emission result of different ZnO nanostructure based systems to that of our present work.

Sl no.	Sample	Synthesis method	E _To at (V μm⁻¹)	Electrode distance (μm)	Improvement [(E_To2 − E_To1)/E_To1] × 100 (%)	Ref.
1	Pd-adsorbed ZnO	Sputtering/wet chemical	6.4–6.6 at 10 μA cm⁻²	Not disclosed	3.12	34
2	In doped ZnO	Thermal oxidation	7.1 10 μA cm⁻²	Not disclosed	N/A	35
3	Ni doped ZnO nanowires and nano-tips	Thermal evaporation	3.25 for nanowires	Not disclosed	112	36
3	Ni doped ZnO nanowires and nano-tips	Thermal evaporation	1.53 for nanotips at 100 μA cm⁻²	Not disclosed	112	36
4	Sn doped ZnO tetrapod	Thermal evaporation	3.91–1.96 at 10 μA cm⁻²	500	99	60
5	Ni doped ZnO	Wet chemical	2.5–2.3 at 1 μA cm⁻²	Not disclosed	8	37
6	ZnO NW	MOCVD	4.1 at 10 μA cm⁻²	Not disclosed	N/A	61
7	CNT-ZnO hybrid	Solid state heating	9.7–2.6 at 10 μA cm⁻²	Not disclosed	273	62
8	Ge doped ZnO NW	CVD	4.1–3.5 at 10 μA cm⁻²	300	17	63
9	Cu doped ZnO QD	Wet chemical	5.89–5.04 10 μA cm⁻²	500	16.8	64
10	Al doped ZnO NRAs/graphene	CVD/sputtering/wet chemical	1.80 V mm⁻¹	170	N/A	65
	Cu doped ZnO NRAs/graphene		1.51 V mm⁻¹
	Cu doped ZnO NRAs/graphene		Not defined
11	Ni doped ZnO NR	Wet chemical	2.84–5.34 1 μA cm⁻²	300	88	Present work