A Review of the Technological Advances in the Design of Highly Efficient Perovskite Solar Cells

Table 2

Some of the HTMs utilized in perovskite solar cells [70, 133].

Review of organic, inorganic, and carbonaceous hole-transport materials for perovskite solar cell applications	(1) Inorganic HTMs: (i) P–type semiconductors-based HTMs: CuPc, CuSCN; (ii) Transition metal-based HTMs; (iii) Nickel & copper-based HTMs: NiO, CuI, Cu2O, CuO, CuCrO2CuGaO2; (iv) MoO3, V2O5, VOx, WOx
	(2) Organic HTMs: (i) Small molecule-based HTMs: pyrene, thiophene, porphyrin, carbazole; (ii) Long polymer-based HTMs: Spiro-OMeTAD, fluorine doped Spiro-; (iii) OMeTAD and MoOx (interlayer in Spiro-OMeTAD), PEDOT: PSS, P3HT, and PTAA; (3) Carbonaceous HTMs/electrode: (i) Conducting carbon, CNTs, GO, r-GO