Molecular Structure Effects on Ionic Diode Performance in Desalination:Ultrahigh Rectification in Butylated Intrinsically Microporous Polyamine (PIM-EA-TB)

Ionic diodes are components in ionic circuits for AC-electricity driven desalination and ion extraction processes. Independent of the ionic diode type/mechanism, achieving ionic current rectification at high ionic strengths is challenging but important, for example in seawater desalination and treatment of brine. Here, the butylation of a molecularly rigid (glassy) polymer of intrinsic microporosity (PIM-EA-TB) is shown to give anionic diodes with ultrahigh rectification effects (associated with interfacial resistivity) even in high ionic strength aqueous 2 M NaCl solution. The effect is rationalised based on polymer structure affecting ion transport

Correlating molecular precursor interactions with device performance in solution-processed Cu2ZnSn(S,Se)4 thin-film solar cells

Research efforts aimed at improving the crystal quality of solution-processed Cu2ZnSn(S,Se)4 (CZTSSe) absorbers have largely employed delicate pre- and post-processing strategies, such as multi-step selenization, heat treatment in mixed chalcogen atmospheres, and multinary extrinsic doping that are often complex and difficult to reproduce. On the other hand, understanding and tunning chemical interactions in precursor inks prior to the thin-film deposition have received significant less attention. Herein, we show for the first time how the complexation of metallic and chalcogen precursors in solution have a stark influence on the crystallization and optoelectronic quality of CZTSSe absorbers. By varying thiourea to metal cation ratios (TU/M) in dimethylformamide (DMF) and isopropyl alcohol (IPA) based inks, we observed the formation of nanoscale metal-organic complexes and sub-micron size aggregates which play a key role in the morphology of the precursor layers obtained by spin-coating and drying steps. We also identify the primary cations in the complexation and assembling processes in solution. The morphology of the precursor film, in turn, has an important effect on grain growth and film absorber structure after the reactive annealing in the presence of Se. Finally, we establish a link between metal complexes in precursor solutions and device performance, with power conversion efficiency increasing from approximately 2% to 8% depending on the TU/M and Cu/(Zn+Sn) ratios

Low-Temperature Growth of Indium Oxide Thin Film by Plasma-Enhanced Atomic Layer Deposition Using Liquid Dimethyl(<i>N</i>‑ethoxy-2,2-dimethylpropanamido)indium for High-Mobility Thin Film Transistor Application

Low-temperature growth of In₂O₃ films was demonstrated at 70–250 °C by plasma-enhanced atomic layer deposition (PEALD) using a newly synthesized liquid indium precursor, dimethyl­(<i>N</i>-ethoxy-2,2-dimethylcarboxylicpropanamide)­indium (Me₂In­(EDPA)), and O₂ plasma for application to high-mobility thin film transistors. Self-limiting In₂O₃ PEALD growth was observed with a saturated growth rate of approximately 0.053 nm/cycle in an ALD temperature window of 90–180 °C. As-deposited In₂O₃ films showed negligible residual impurity, film densities as high as 6.64–7.16 g/cm³, smooth surface morphology with a root-mean-square (RMS) roughness of approximately 0.2 nm, and semiconducting level carrier concentrations of 10¹⁷–10¹⁸ cm^–3. Ultrathin In₂O₃ channel-based thin film transistors (TFTs) were fabricated in a coplanar bottom gate structure, and their electrical performances were evaluated. Because of the excellent quality of In₂O₃ films, superior electronic switching performances were achieved with high field effect mobilities of 28–30 and 16–19 cm²/V·s in the linear and saturation regimes, respectively. Furthermore, the fabricated TFTs showed excellent gate control characteristics in terms of subthreshold swing, hysteresis, and on/off current ratio. The low-temperature PEALD process for high-quality In₂O₃ films using the developed novel In precursor can be widely used in a variety of applications such as microelectronics, displays, energy devices, and sensors, especially at temperatures compatible with organic substrates