| Abstract [eng] |
During the early development of perovskite solar cells (PSCs), the selection of organic hole-transporting materials (HTMs) was very limited. The main reason for this problem was a lack of understanding about the structures required to achieve high efficiency of the devices. The most popular low-molar-mass HTM used in PSCs is 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene. The synthesis of this compound consists of six steps. In addition, aggressive and sensitive reagents are used. The thesis is devoted to the synthesis and investigation of new, cost-effective, organic HTMs for PSCs. Taking into account that development of HTMs for additive-free PSCs is an urgent issue, the author of the thesis designed, synthesized, and studied several series of new low-molecular-mass organic HTMs. A number of publications that describe a simple pathways for the synthesis of efficient HTMs with branched structures forming stable molecular glasses were prepared. N,N-di(4-methoxyphenyl)hydrazones and the corresponding dihydrazones of carbazole and phenothiazine carbaldehydes were designed and synthesized using cost-effective synthetic strategies. Their properties were studied. Dibenzothiophene based derivatives for the stable additive-free PSCs were also prepared. Due to their high conductivity in the pristine state, HTMs can be used without dopants and allow to achieve encouraging power conversion efficiency of PSCs of 20.9%. Triphenylamine based enamines also enable to obtain PSCs exhibiting long-term stability, which is important for commercial application. The dioant free hole-transporting layers of indolo[3,2-b]carbazole derivatives also can be used for the fabrication of efficient PSCs. The devices with pristine layers of these HTMs have shown a very promising power conversion efficiency of 19.45%. |
