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Abstract Interfacial compatibility between the electrode and organic semiconductor plays a critical role in controlling the charge transport and hence efficiency of organic solar cell. Here, we introduce a novel small-molecule zwitterionic electrolyte (S1) combined with ZnO as electron transporting interlayer employed for the inverted PTB7:PC 71 BM bulk heterojunction solar cell. The resulting device with the S1/ZnO stacked interlayer achieves a high PCE of 8.59%, obtaining a 16.2% improvement over the control device performance of 7.4% without the S1 attributed to the significant increased short-circuit current density and fill factor. The interfacial properties are investigated. It is found that the S1/ZnO interlayer possess an ultralow work function of 3.6 eV, which originates from the interfacial double dipole step induced by the zwitterionic side chain electrostatic realignment at interface. The S1/ZnO interlayer exhibits the excellent charge extraction ability, suppresses the charge recombination loss and decreases the series resistance at the active layer/electrode contact. Graphical abstract Image 1 Highlights • S1 coated ZnO layer is employed as electron transporting layer for inverted organic solar cell. • S1/ZnO stacked interlayer exhibits the excellent charge extraction ability. • ZnO/S1 stacked interlayer has an ultralow work function of 3.6 eV. • The efficiency of the device with the S1/ZnO interlayer constitutes a 16.2% improvement over that of the controlled device. [ABSTRACT FROM AUTHOR]

The demonstration of an efficient nanostructure that provides acceptable photoelectrochemical water splitting properties using the sun visible radiation is an appealing issue. In this connection, a new ternary nanocomposite of Ag 2 S/MoS 2 /ZnO photoanode is subsequently fabricated via hydrothermal, solvothermal and SILAR methods. Different properties of the nanocomposite are characterized by XRD, SEM, EDX, XPS, UV–Vis-IR spectroscopy and electrochemical techniques. The post-grown annealed 8-Ag 2 S/MoS 2 /ZnO photoanode exhibits a good performance with a photocurrent density of 2 mA/cm2 at a bias potential 1.23 V vs. RHE. The photocurrent of the post-grown annealed 8-Ag 2 S/MoS 2 /ZnO photoanode is 71.42 times, 40 times and 2 times higher compares to the pure ZnO, post-grown annealed MoS 2 /ZnO, and post-grown annealed 8-Ag 2 S/ZnO photoanodes, respectively. The enhanced PEC performance may originate from the combination of different effects such as the expansion of light absorption and energy band alignment (type II heterostructures), [SO 4 ] acted as a charge-transfer medium, and electrode-electrolyte interface kinetic reactions. [Display omitted] • Ag 2 S/MoS 2 /ZnO ternary nanocomposite was successfully synthesized in three steps. • This ternary photoanode greatly improved the photocurrent of the PEC water splitting. • Ag 2 S components are utilized as light-absorption sensitizers. • The sacrificial reagent electrolyte is used to study the reactions. [ABSTRACT FROM AUTHOR]

Two phase-pure nanocrystalline anatase materials differing in the exposed crystal facets (0 0 1) or (1 0 1) are studied by electrochemical impedance spectroscopy and by transient photovoltage and photocurrent decay in dye sensitized solar cells. A larger chemical capacitance, indicating larger density of states, is observed for anatase (0 0 1). The presence of deep electron traps in (0 0 1) nanosheets is further confirmed by optical (UV-Vis) and photoemission (XPS, UPS) spectra. The difference in chemical capacitance indicates a slower diffusion of electrons in the (0 0 1) anatase material, but also a higher electron lifetime compared to (1 0 1) anatase material. [ABSTRACT FROM AUTHOR]

[Display omitted] • The hybrid HTL consists of MoS 2 nanosheets and a PEDOT derivative, which results in an obvious improvement in organic solar cells' performance. • We identified that the synergy of exfoliated-MoS 2 nanosheets and DA-P result in better hole transport and extraction through systematic investigations. • By applying a comprehensive range of spectroscopies, we discovered that the dopant is derived from the oxidation products of MoS 2 nanosheets during ultrasonic exfoliation. We report an efficient hole transporting layer (HTL) for organic solar cell (OSC) based on solution-processed organic-inorganic hybrid composed of ultrasonic-exfoliated MoS 2 nanosheets and dopamine-copolymerized poly(3,4-ethylenedioxythiophene) (PEDOT) derivative (DA-P). The OSCs based on this new hybrid HTL show a marked performance improvement over those with single-component HTLs, and they retain up to 80% of their original power conversion efficiency after 35 days. Our investigations reveal that the boost in performance is due to a synergistic effect that improves both hole transport and extraction ability. This effect is mainly due to the doping of exfoliated-MoS 2 nanosheets on DA-P. We employ a comprehensive range of spectroscopies to uncover that the dopant is derived from the oxidation products of MoS 2 nanosheets during the ultrasonic exfoliation. Our work demonstrates an efficient hybrid HTL and offers new insights into the interaction of exfoliated-MoS 2 nanosheets and the PEDOT derivatives. [ABSTRACT FROM AUTHOR]