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Abstract The potential of porphyrin derivatives as hole-transporting materials (HTMs) for perovskite solar cells (PSCs) has been demonstrated. The structural engineering of porphyrin HTMs provides an important means for further improvement of the performance of PSCs. Herein, a zinc-porphyrin derivative (ZnP-FL) decorated with four fluorene-terminated triarylamines is presented. The lab synthesis cost of ZnP-FL is estimated to be around $32.2/g. It exhibits good charge-transport ability and thermal stability. A high power conversion efficiency (PCE) of 19.31% is achieved by using ZnP-FL HTM (V oc = 1.08 V; J sc = 24.08 mA · cm−2), which is distinctly higher than that of a control HTM without the fluorene groups (PCE = 17.75%; V oc = 0.97 V; J sc = 24.04 mA · cm−2). This performance enhancement is mainly attributed to the improved open-circuit voltage, which benefits from the stabilized HOMO level of ZnP-FL. In addition, the porphyrin HTM-based PSCs show superior air and thermal stability to the device with the standard HTM spiro-OMeTAD. These results demonstrate that the low-cost and easily accessible porphyrin derivatives are promising HTMs for efficient and stable PSCs.

Nano‐fluids' application for enhanced oil recovery (EOR) has attracted noticeable attention and formed a new research area in recent years. Currently, the greatest challenge in this area is to formulate stable nano‐fluids for oil reservoirs with high temperatures and salinity. To overcome the limitations of its application in high‐temperature drilling, polymer‐coated nanoparticles (SiO2‐PAMPS NPs) were prepared via solution polymerization of 2‐acrylamide‐2‐methyl‐1‐propane sulphonic acid (AMPS) from the surface of aminopropyl‐functionalized silica nanoparticles. The SiO2‐PAMPS NPs were characterized by Fourier‐transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and dynamic light scattering (DLS). The results indicated that the AMPS was successfully grafted onto the surface of silica nanoparticles, and the average diameter of SiO2‐PAMPS NPs was about 16 nm. The nano‐fluids showed noticeable stability in American Petroleum Institute (API) brine (2 wt.% CaCl2 and 8 wt.% NaCl) at 90°C beyond 46 days. When amphipathic nanoparticles were introduced to brine at 90°C, the potential of the nano‐fluids in recovering oil was evaluated by investigating the interfacial tension with kerosene oil and the oil contact angle in the nano‐fluids. The contact angle of the glass sheet surface before treatment was about 144°, while after SiO2‐PAMPS NPs treatment for 72 h, it became about 92°. Meanwhile, the nano‐fluids showed an excellent enhancing emulsibility property, which plays a vital role in promoting the development of EOR in high‐temperature and high‐salt environments. [ABSTRACT FROM AUTHOR]

The study of molecular interactions of drug-protein are extremely important from the biological aspect in all living organisms, and therefore such type of investigation hold a tremendous significance in rational drug design and discovery. In the present study, the molecular interactions between paromomycin (PAR) and human serum albumin (HSA) have been studied by different biophysical techniques and validated by in-silico approaches. The results obtained from Ultraviolet–visible spectroscopy (UV) and Fourier transform infrared spectroscopy (FT-IR) demonstrated a remarkable change upon the complexation of PAR with HSA. Circular Dichroism (CD), Dynamic Light Scattering (DLS) and Resonance Rayleigh scattering (RRS) results revealed a significant secondary structure alteration and reduction of hydrodynamic radii upon the conjugation of PAR with HSA. The fluorescence spectroscopy results also apparently revealed the static quenching mechanism. The number of binding sites, binding constants, and Gibbs free energy values were calculated to illustrate the nature of intermolecular interactions. Similarly, the in-silico docking and molecular dynamics simulation clearly explain the theoretical basis of the binding mechanism of PAR with HSA. The experimental and docking approaches suggested that PAR binds to the hydrophobic cavity site I of HSA. The finding of present investigation will provide binding insight of PAR and associated alterations in the stability and conformation of HSA. [ABSTRACT FROM AUTHOR]

A novel multi-functional interface material (TAAPyr) is first developed as a defect passivation layer and a protect layer against moisture for PSCs application. Consequently, the efficiency of TAAPyr-based device can increase form 20.37% to 22.45%, with an unencapsulated device retaining 90% of its initial efficiency after storage for 600h at ∼65% humidity. [Display omitted] • A hydrophobic multi-functional interface material is developed for PSCs application. • TAAPyr-treated PSCs shows an improvement in efficiency from 20.37% to 22.45%. • Device long-term stability has greatly been enhanced. Surface treatment of perovskite films with interface materials is an effective strategy to resolve trap-mediated nonradiative recombination toward high efficiency and stability of perovskite solar cells (PSCs). However, interface materials for multi-functional treatment have been rarely investigated in PSCs. In this work, a novel pyrene-based organic material (TAAPyr) is first introduced as a defect passivation layer and a protect layer against moisture for PSCs application. With the TAAPyr interfacial modification, both perovskite surface defects and nonradiative recombination are effectively decreased as well as the carrier transport in device is also enhanced, As a consequence, the best power conversion efficiencies (PCE) up to 22.45% for TAAPyr-based device was obtained, clearly outperforming the control one (20.37%). Moreover, it was found that the π-conjugated TAAPyr can promote intermolecular face-to-face stacking on the surface perovskite film, which is favorable to making the perovskite surface more hydrophobic and consequently enhance PSCs long-term stability. The un-encapsulated PSCs can retain 92% of the initial PCE after storage for 600 h at ∼65% RH, in comparison with 64% efficiency retention of the device without TAAPyr under the same conditions. This work presents a new strategy to enhance the efficiency and stability of PSCs by multi-functional π–conjugated passivator. [ABSTRACT FROM AUTHOR]