Alkyl side-chain dependent self-organization of small molecule and its application in high-performance organic and perovskite solar cells

Oh, Sangsuk; Khan, Nasir; Jin, Seon-Mi; Tran, Huyen; Yoon, Namsun; Song, Chang Eun; Lee, Hang Ken; Shin, Won Suk; Lee, Jong‐Cheol; Moon, Sang‐Jin; Lee, Eunji; Lee, Sang Kyu

doi:10.1016/j.nanoen.2020.104708

Cited by 22 publications

(19 citation statements)

References 79 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[ 10 ] We also considered the solubility issues encountered with prototype Ullazine HTMs, [ 10 ] and the significant impact of alkyl side‐chains on the morphology, charge transport, and interfacial properties of small molecule HTM films. [ 13 ] Accordingly, thienyl functionalized Ullazines bearing highly lipophilic 2‐ethylhexyl substituents were targeted.…”

Section: Introductionmentioning

confidence: 99%

Molecular Engineering of Thienyl Functionalized Ullazines as Hole‐Transporting Materials for Perovskite Solar Cells

et al. 2021

View full text Add to dashboard Cite

Organic hole‐transporting materials (HTMs) based on the Ullazine core yield so far only moderate power conversion efficiencies of up to 13.08% in perovskite solar cells (PSCs). Aiming to fabricate efficient and stable PSCs, novel Ullazine derivatives bearing thiophene units were designed and synthesized, allowing modulation of the electronic states of the HTMs and further providing defect passivation of the perovskite surface. Experimental and theoretical analysis show that thiophene units with ‐N(p‐MeOC6H4)2 groups improve the conductivity of Ullazine HTMs, boosting the efficiency of PSCs to 20.21%. This value is the highest reported to date for Ullazine‐based HTMs, and is close to the performance of Spiro‐OMeTAD. In addition, unencapsulated PSCs based on the champion Ullazine exhibit superior stability with respect to Spiro‐OMeTAD, retaining nearly 90% of the initial efficiency following 1000 h aging, which is ascribed to a combination of higher water repellency and passivation of defects on the perovskite surface. This work demonstrates the high potential of HTMs based on Ullazine core as substitutes to Spiro‐OMeTAD.

show abstract

Section: Introductionmentioning

confidence: 99%

Molecular Engineering of Thienyl Functionalized Ullazines as Hole‐Transporting Materials for Perovskite Solar Cells

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Among a big variety of organic hole-transport materials reported to date, small molecules are particularly attractive since they are individual compounds with well-defined molecular structures, which can be extensively purified such that it guarantees reproducibility of their optoelectronic and physicochemical characteristics. − Impressive progress has been achieved in this field by using such families of compounds as different spiro compounds, triarylamines and carbazoles, porphyrins and phthalocyanines, , substituted dithienopyrroles, compounds with truxene and triazatruxene cores, and benzodithiophene and benzotrithiophene derivatives. , However, despite such a broad diversity of different types of hole-transport materials reported to date, it is still unclear which structural features and optoelectronic and physicochemical properties are required for achieving a high photovoltaic performance of the designed materials in perovskite solar cells.…”

Section: Introductionmentioning

confidence: 99%

Design Principles for Organic Small Molecule Hole-Transport Materials for Perovskite Solar Cells: Film Morphology Matters

Latypova

Emelianov

Balakirev

et al. 2022

ACS Appl. Energy Mater.

View full text Add to dashboard Cite

High-efficiency n–i–p perovskite solar cells generally incorporate organic hole-transport layer materials such as spiro-OMeTAD or PTAA, which have intrinsically low charge carrier mobility and therefore require doping to improve transport properties. However, using dopants is known to affect badly the operational stability of perovskite solar cells. Therefore, the development of suitable dopant-free hole-transport materials is the critical issue for realizing perovskite solar cells with high efficiency and long operational lifetimes. Herein, a series of small molecules with triazatruxene, benzodithiophene, triphenylamine, and dithienosilole electron donor core units were designed and explored as solution-processed dopant-free hole-transport materials for perovskite solar cells. The best performance has been obtained using the triazatruxene-based molecule TAT-2T-CNA with terminal alkyl cyanoacetate groups and a 2,2′-bithiophene π-conjugated bridge, which has enabled device efficiency of 20.1% with negligible hysteresis, along with a substantially improved V OC and FF values as compared to the reference devices assembled with PTA as a hole-transport material. The superior performance of TAT-2T-CNA is attributed to the optimal optoelectronic properties of this material and, most importantly, defectless film morphology. Using scanning near-field infrared microscopy (IR-SNOM) technique was shown to be particularly useful for the detection and visualization of defects in thin films of hole-transport materials, which strongly correlate with the device performance. The results obtained in this work are expected to provide new insights facilitating the rational design of efficient dopant-free hole-transport materials for efficient and stable perovskite solar cells.

show abstract

“…[1][2][3][4] The organic chromophores with conjugated structures have been widely probed in solution-processed bulk-heterojunction OSCs (BHJ-OSCs) due to their inherent advantages of chemical synthesis, inclusive bandgap tuning, facile solution casting, and high flexibility. [5][6][7][8][9] Currently, power conversion efficiency (PCE) of OSCs with donor-acceptor (D-A) materials has reached over $15% which is mostly enabled either by non-fullerene derivative or ternary OSCs. [10][11][12][13][14][15][16][17][18] In the recent study, $17.1% PCE is reported by Lin et al for single-junction OSCs which came to exist by the BHJ doped with n-type benzyl viologen dopant.…”

Section: Introductionmentioning

confidence: 99%

“…Third‐generation organic solar cells (OSCs) with the donor–acceptor molecular network have emerged as one of the fast‐growing photovoltaic technologies to convert the perpetual sunlight into electricity through abundant organic semiconducting materials at low cost 1‐4 . The organic chromophores with conjugated structures have been widely probed in solution‐processed bulk‐heterojunction OSCs (BHJ‐OSCs) due to their inherent advantages of chemical synthesis, inclusive bandgap tuning, facile solution casting, and high flexibility 5‐9 . Currently, power conversion efficiency (PCE) of OSCs with donor–acceptor (D–A) materials has reached over ~15% which is mostly enabled either by non‐fullerene derivative or ternary OSCs 10‐18 .…”

Section: Introductionmentioning

confidence: 99%

Highly stable bulk heterojunction organic solar cells based on asymmetric benzoselenadiazole‐oriented organic chromophores

Abdullah

Kim

Akhtar

et al. 2022

Intl J of Energy Research

View full text Add to dashboard Cite

Summary A new asymmetrically designed D‐A‐D organic chromophore 4‐(7‐(5′‐hexyl‐[2,2′‐bithiophen]‐5‐yl)benzo[c][1,2,5]selenadiazol‐4‐yl)‐N,N‐diphenylaniline (RSeT) with benzoselenadiazole acceptor unit has been synthesized using two different electron donor materials of triphenylamine (TPA) and n‐hexyl bithiophene unit. Attachment of nonplanar electron‐donating TPA unit subsequently heightened the optoelectronic properties and altered the solubility in organic solvents. RSeT of the optical bandgap of ~1.95 eV with the highest occupied molecular orbital and lowest unoccupied molecular orbital energy levels of −5.31 and −3.36 eV was applied as an electron donor material for stable bulk heterojunction organic solar cells. In this work, two different buffer layers of poly (3, 4‐ethylenedioxythiophene):polystyrene sulfonate acid (PEDOT:PSS) and compact titanium oxide (c‐TiO2) were used and their influences on the device performance were investigated. Buffer layer of c‐TiO2 with RSeT:PC61BM (1:3, w/w) active layer achieved a high open‐circuit voltage (Voc) of ~0.985 V, short‐circuit current density (Jsc) of ~11.26 mA/cm2 and improved fill factor of ~0.62 which resulted in a high power conversion efficiency (PCE) of ~6.88%. After 30 days, interestingly, RSeT:PC61BM (1:3, w/w) devices with a c‐TiO2 buffer layer demonstrated good stability with the PCE value remaining at 85% of its initial value.

show abstract

Alkyl side-chain dependent self-organization of small molecule and its application in high-performance organic and perovskite solar cells

Cited by 22 publications

References 79 publications

Molecular Engineering of Thienyl Functionalized Ullazines as Hole‐Transporting Materials for Perovskite Solar Cells

Molecular Engineering of Thienyl Functionalized Ullazines as Hole‐Transporting Materials for Perovskite Solar Cells

Design Principles for Organic Small Molecule Hole-Transport Materials for Perovskite Solar Cells: Film Morphology Matters

Highly stable bulk heterojunction organic solar cells based on asymmetric benzoselenadiazole‐oriented organic chromophores

Contact Info

Product

Resources

About