Search

Antimony selenosulfide (Sb2(S,Se)3) solar cells are critically restrained by the Sb2(S,Se)3/charge transport layer interface with scarce carriers transfer ability and high density of deep‐level defect‐induced traps, which are prone to spark the nonradiative recombination and capture the benign photogenerated carriers. Herein, utilizing the intermolecular noncovalent interactions strategy in molecular stereoscopic structural engineering, two dopant‐free hole transport materials (HTMs) are constructed, coded as T‐BDT and F‐BDT, with synergistic hole selectivity and interfacial healing ability. The theoretical simulation and experimental results decipher that the F‐BDT possesses the more favorable planarized conformation, charge delocalization/coupling and molecular stacking pattern, which endow it with the salient hole selection, robust interface passivation and appropriate energy level alignment. Consequently, the Sb2(S,Se)3 solar cell with F‐BDT as dopant‐free HTM realize an outstanding power conversion efficiency of 9.13%, hitting the record high for Sb2(S,Se)3 devices under dopant‐free conditions. [ABSTRACT FROM AUTHOR]

Herein, Na2SSeO3 solutions are prepared by hydrothermal method at 140 °C for 8 h using Se powder and Na2SO3 solution (the molar ratios of Se:Na2SO3 = 1:4, 1:5, 1:6) and the chemical composition of Na2SSeO3 solutions is analyzed by X‐ray photoelectron spectroscopy. Sb2SySe3−y thin films are prepared by chemical bath deposition (CBD) at 90 °C for 5 h and subsequently annealed at 375 °C for 10 min and etched by N‐butyldithiocarbamic acid solution in DMF. The effect of the Na2SSeO3 solution, growth solution volume, etching on the thickness and chemical composition of Sb2SySe3−y thin films, and the power conversion efficiency (PCE) of the corresponding solar cells is systematically investigated. The result reveals that the Na2SSeO3 solutions may be the mixing solutions containing Na2SSeO3, Na2S2SeO6, Na2S2Se2O6, Na2Se. When the molar ratio of Se:Na2SO3 and growth solution volume is 1:5 and 56 mL and the Sb2SySe3−y thin films with annealing are etched, the PCE of Sb2SySe3−y solar cells is 8.00% with spiro‐OMeTAD and 8.43% with spiro‐OMeTAD:TMT‐TTF. The PCE of 8.43% is the highest value for Sb2SySe3−y solar cells using CBD and demonstrates that the composition engineering is an important strategy for improving the PCE of Sb2SySe3−y solar cells using CBD. [ABSTRACT FROM AUTHOR]

The fine structural–functional construction of organic semiconductor materials provides an abundant candidate store for the hole‐transport materials (HTMs) in perovskite solar cells (PSCs). Whereas, challenges remain in unveiling the clews behind the molecular conformation engineering and desired properties realizing for efficient HTMs. In this work, a couple of simple organic diphenylfluorene‐cored isomers (FH27 and FH99) with different spatial integration strategies of molecular conformation are judiciously devised as HTMs in the PSCs. The theoretical simulation and experimental analyses decipher that the excellent electronic/energetic distribution, intermolecular stacking geometry, intrinsic solid‐crystal film morphology, and charge‐extraction‐transport ability are demonstrated for FH27, ascribing to its harmonious intersectional couplings for the planar/orthogonal molecular conformation. The FH27‐based device achieves a high efficiency of 23.61% with benign life span, both superior to the FH99‐based device. [ABSTRACT FROM AUTHOR]

In this work, Sb2S3 thin films were successfully prepared by chemical bath deposition (CBD) using the mixing solution of SbCl3 and sodium citrate as a novel Sb source. The influence of the solution chemical composition, deposition process parameters, CdS thin film microstructure on the properties of Sb2S3 thin films and the photovoltaic performance of the corresponding solar cells was systematically investigated. The CBD growth mechanism of Sb2S3 thin films was explored from the thickness increase and the molar ratio evaluation of Sb–O : Sb–S/O. The result revealed that the CBD growth process of Sb2S3 thin films was dominated by the nanoparticle formation–adsorption pathway. When the SbCl3 concentration was 120 mM, the molar ratio of SbCl3 : sodium citrate : Na2S2O3 : thioacetamide was 1 : 2.3 : 1.5 : 0.5, the growth solution volume was 48 mL, the growth temperature and time were 90 °C and 6 h, and the Sb2S3 solar cell with the architecture of FTO/CdS/Sb2S3/spiro-OMeTAD:TMT-TTF/Au achieved a power conversion efficiency (PCE) of 7.63%, along with an open-circuit voltage of 0.78 V, a short-circuit photocurrent density of 16.89 mA cm−2, and a fill factor of 0.58. The PCE of 7.63% was relatively high in Sb2S3 solar cells and the application for the mixing solution of SbCl3 and sodium citrate as the Sb source can open up a broad space for the preparation of antimony chalcogenide thin films. [ABSTRACT FROM AUTHOR]

SnO2 is one of the most used inorganic electron transport materials for organic‐inorganic halide perovskite solar cells. However, the surface defects of SnO2 will block the electron transport at the SnO2/perovskite buried interface and limit the device performance. Here, poly(acrylic acid) (PAA) is employed to modify the SnO2 electron transport layer. Carboxyl groups can react with KOH in the commercial SnO2 aqueous colloidal dispersion to produce potassium polyacrylate, the −COO− can combine not only with oxygen and Sn4+ on SnO2, but also can chelate with uncoordinated Pb2+ defects on perovskite. Moreover, carboxyl groups can form a chemical linker between SnO2 and perovskite via the esterification reaction, leading to the reduction of surface hydroxyl group defects of SnO2. The optimal solar cells with PAA modification achieve an enhanced power conversion efficiency of 18.88 % and improved stability. [ABSTRACT FROM AUTHOR]

Herein, Sb2S3 thin films are successfully prepared by hydrothermal method using the mixing solution of SbCl3 and sodium citrate as a novel Sb source. The influence of the growth temperature and time, growth solution volume on the properties of Sb2S3 thin films, and the photovoltaic performance of the corresponding solar cells is systematically investigated. The results reveal that the thickness and Sb–O content in Sb2S3 thin films decrease with the increase of the growth temperature and growth solution volume and decrease of the growth time. When the chemical composition and volume of the growth solution are 120 mM SbCl3, 276 mM sodium citrate, 180 mM Na2S2O3, 60 mM thioacetamide, and 28 mL, and the growth temperature and time are 150 °C and 2 h, the thickness and molar ratios of Sb–O:Sb–S/O in Sb2S3 thin films are 295 nm and 0.14 and the corresponding solar cells achieve the power conversion efficiency (PCE) of 7.36%, which is the highest PCE in Sb2S3 solar cells using hydrothermal method. Therefore, the effect of the growth temperature and time, specially the growth solution volume, on the thickness and Sb–O content in Sb2S3 thin films is important for improving the PCE of Sb2S3 solar cells. [ABSTRACT FROM AUTHOR]