Most nonfullerene acceptors developed so far for high-performance organic solar cells (OSCs) are designed in planar molecular geometry containing a fused-ring core. In this work, a new nonfullerene acceptor of DF-PCIC is synthesized with an unfused-ring core containing two cyclopentadithiophene (CPDT) moieties and one 2,5-difluorobenzene (DFB) group. A nearly planar geometry is realized through the F···H noncovalent interaction between CPDT and DFB for DF-PCIC. After proper optimizations, the OSCs with DF-PCIC as the acceptor and the polymer PBDB-T as the donor yield the best power conversion efficiency (PCE) of 10.14% with a high fill factor of 0.72. To the best of our knowledge, this efficiency is among the highest values for the OSCs with nonfullerene acceptors owning unfused-ring cores. Furthermore, no obvious morphological changes are observed for the thermally treated PBDB-T:DF-PCIC blended films, and the relevant devices can keep ≈70% of the original PCEs upon thermal treatment at 180 °C for 12 h. This tolerance of such a high temperature for so long time is rarely reported for fullerene-free OSCs, which might be due to the unique unfused-ring core of DF-PCIC. Therefore, the work provides new idea for the design of new nonfullerene acceptors applicable in commercial OSCs in the future.

In situ attenuated total reflection surface-enhanced infrared absorption spectroscopy in conjunction with H–D isotope replacement is used to investigate the dissociation and oxidation of CH3CH2OH on a Pd electrode in 0.1 M NaOH, with a focus on identifying the chemical nature of the pivotal intermediate in the so-called dual-pathway (C1 and C2) reaction mechanism. Real-time spectroelectrochemical measurements reveal a band at ∼1625 cm–1 showing up prior to the multiply bonded COad band. CH3CD2OH and D2O are used to exclude the spectral interference with this band from interfacial acetaldehyde and H2O, respectively, confirming for the first time that the ∼1625 cm–1 band is due to the adsorbed acetyl on the Pd electrode in alkaline media. The spectral results suggest that the as-adsorbed acetyl (CH3COad) is oxidized to acetate from approximately −0.4 V as the potential moves positively to conclude the C2 pathway. Alternatively, in the C1 pathway, the CH3COad is decomposed to α-COad and β-CH x species on the Pd electrode at potentials more negative than approximately −0.1 V; the α-COad species is oxidized to CO2 at potentials more positive than approximately −0.3 V, while the β-CH x species may be first converted to COad at approximately −0.1 V and further oxidized to CO2 at more positive potentials.

To search for robust CO2 capture materials, several N-(3-aminopropyl)aminoethyl tributylphosphonium amino acid salts ([apaeP444][AA])-type task specific ionic liquids (TSILs) were synthesized and immobilized into porous silica support through a facile impregnation–vaporization method. The ILs and thus prepared sorbents, Sorb-AA, were well characterized, and their CO2 sorption and desorption behaviors under temperature- and vacuum-swing conditions were investigated. The ILs can be immobilized facilely into silica up to 1/1 IL/SiO2 weight ratio. After IL loading, the sorbents retain reasonably high specific surface area and porosity and therefore exhibit rapid sorption and desorption rates as well as excellent sorption capacity and selectivity and can be used repeatedly. Among them, Sorb-Lys has the highest CO2 sorption capacity. It can capture 1.54 mmol or 67.9 mg CO2 per gram sorbent from a simulated flue gas containing 14% CO2 in each cycle of sorption and desorption. Sorb-Gly has slightly less CO2 sorption capacity, 1.37 mmol or 60.4 mg CO2 per gram sorbent from the simulated flue gas, and much better long-term durability. It is estimated that it can retain 90% sorption capacity even after 1.38 × 103 cycles. These robust sorbents, especially Sorb-Gly, exhibit excellent potential in CO2 capture applications.

Low-dimensional organometallic halide perovskites are actively studied for the light-emitting applications due to their properties such as solution processability, high luminescence quantum yield, large exciton binding energy, and tunable band gap. Introduction of large-group ammonium halides not only serves as a convenient and versatile method to obtain layered perovskites but also allows the exploitation of the energy-funneling process to achieve a high-efficiency light emission. Herein, we investigate the influence of the addition of ethylammonium bromide on the morphology, crystallite structure, and optical properties of the resultant perovskite materials and report that the phase transition from bulk to layered perovskite occurs in the presence of excess ethylammonium bromide. On the basis of this strategy, we report green perovskite light-emitting devices with the maximum external quantum efficiency of ca. 3% and power efficiency of 9.3 lm/W. Notably, blue layered perovskite light-emitting devices with the Commission Internationale de I'Eclairage coordinates of (0.16, 0.23) exhibit the maximum external quantum efficiency of 2.6% and power efficiency of 1 lm/W at 100 cd/m, representing a large improvement over the previously reported analogous devices.

Organic solar cells (OSCs) with visible transparency and vivid colors are promising for deployment in building-integrated photovoltaics (BIPVs), yet significant challenges remain to be addressed for not only balancing the trade-off between the photovoltaic and optical properties but also controlling the bandpass of visible transmittance for the coloration of semitransparent OSCs (ST-OSCs). Herein ST-OSCs with vivid colors are successfully developed by employing one fixed active blend in the rationally designed device layout with a high-quality Fabry−Peŕot electrode. With the assistance of optical simulation, vividly colorful ST-OSCs have been obtained with power conversion efficiency of >14% and maximum transmittance up to 31%. Overall, this study provides new access to OSCs with promising features as BIPVs.

The dissociative adsorption and electrooxidation of CH(3)OH at a Pd electrode in alkaline solution are investigated by using in situ infrared spectroscopy with both internal and external reflection modes. The former (ATR-SEIRAS) has a higher sensitivity of detecting surface species, and the latter (IRAS) can easily detect dissolved species trapped in a thin-layer-structured electrolyte. Real-time ATR-SEIRAS measurement indicates that CH(3)OH dissociates to CO(ad) species at a Pd electrode accompanied by a "dip" at open circuit potential, whereas deuterium-replaced CH(3)OH doesn't, suggesting that the breaking of the C-H bond is the rate-limiting step for the dissociative adsorption of CH(3)OH. Potential-dependent ATR-SEIRAS and IRAS measurements indicate that CH(3)OH is electrooxidized to formate and/or (bi)carbonate, the relative concentrations of which depend on the potential applied. Specifically, at potentials negative of ca. -0.15 V (vs Ag/AgCl), formate is the predominant product and (bi)carbonate (or CO(2) in the thin-layer structure of IRAS) is more favorable at potentials from -0.15 to 0.10 V. Further oxidation of the CO(ad) intermediate species arising from CH(3)OH dissociation is involved in forming (bi)carbonate at potentials above -0.15 V. Although the partial transformation from interfacial formate to (bi)carbonate may be justified, no bridge-bonded formate species can be detected over the potential range under investigation.

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