Improved Hole Injection in Bulk Heterojunction (BHJ) Hybrid Solar Cells by Applying a Thermally Reduced Graphene Oxide Buffer Layer

Table 2

Summary of device performance parameters of five types of hybrid solar cells with different HTL configurations.

HTL	(V)	(mA/cm^2)	FF	PCE (%)	(Ωcm^2)	(Ωcm^2)
No-HTL	0.4	0.8	0.4	0.1	413.0	126.0
PEDOT:PSS	0.7	7.0	0.5	2.5	515.5	16.3
CNT	0.4	6.7	0.4	1.0	166.9	27.3
rGO	0.7	6.1	0.4	1.7	403.2	31.3
CNT/PEDOT:PSS	0.6	6.7	0.4	1.7	303.3	26.3
rGO^a/PEDOT:PSS	0.7	9.5	0.5	3.2	473.9	10.3
rGO^b/PEDOT:PSS	0.6	6.5	0.6	2.2	448.0	20.0
rGO^c/PEDOT:PSS	0.7	4.2	0.4	1.2	431.1	41.7

rGO^a: thermal reduction in air at 300°C for 1 hour. rGO^b: thermal reduction in a nitrogen environment at 300°C for 1 hour. rGO^c: chemical reduction by thiol functionalization followed by annealing in air at 300°C for 1 hour.