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Abstract The catalytic oxidative dehydrogenation of propane (ODHP) is a challenging reaction due to facile competing overoxidation to CO_x. The gaseous disulfur molecule, S₂, is isoelectronic with O₂and has been shown to act as an alternative, “soft oxidant” for the analogous process (SODHP) over bulk metal sulfide catalysts. However, these bulk catalysts suffer from low surface areas and ill‐defined active sites – issues that might be addressed with a supported catalyst. Here we investigate supported V/Al₂O₃materials for SODHP. We show that these catalysts are highly selective for propylene, far surpassing the yields of the prior bulk systems. Isolated sulfided vanadium species are found to be more active and selective than crystalline vanadium sulfide. Additionally, we compare the S₂and O₂oxidants over sulfided and calcined V/Al₂O₃materials, respectively, and find that the propylene selectivity is enhanced using S₂as the oxidant. These results suggest that sulfur is a promising soft oxidant that can be used to achieve high propylene selectivities over supported metal sulfides. 

Abstract A detailed investigation addressing the effects of functionalizing conjugated polymers with oligo(ethylene glycol) (EG_n) sidechains on the performance and polymer‐electrolyte compatibility of electrochromic devices (ECDs) is reported. The electrochemistry for a series of donor‐acceptor copolymers having near‐infrared (NIR)‐optical absorption, where the donor fragment is 3,4‐ethylenedioxythiophene (EDOT) or an EG_nfunctionalized bithiophene (g2T) and the acceptor fragment is diketopyrrolopyrrole (DPP) functionalized with branched alkyl or EG_nsidechains, is extensively probed. ECDs are next fabricated and it is found that EG_nsidechain incorporation must be finely balanced to promote polymer‐electrolyte compatibility and provide efficient ion exchange. Proper electrolyte‐cation pairing and polymer structural tuning affords a 2x increase in optical contrast (from 12% to 24%) and >60x reduction in switching time (from 20 to 0.3 s). Atomic force microscopy (AFM)/grazing incidence wide‐angle X‐ray scattering (GIWAXS) characterization of the polymer film morphology/microstructure reveals that an over‐abundance of EG_nsidechains generates large polymer crystallites, which can suppress ion exchange. Lastly, time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) indicates sidechain/electrolyte identity does not influence the electrolyte penetration depth into the films, and EG_nsidechain inclusion increases electrolyte cation uptake. The material structural design insight and guidelines regarding the polymer‐electrolyte ion insertion/expulsion dynamics reported here should be of significant utility for developing next‐generation mixed ionic‐electronic conducting materials. 

Abstract Chemical modification is a powerful strategy for tuning the electronic properties of 2D semiconductors. Here we report the electrophilic trifluoromethylation of 2D WSe₂and MoS₂under mild conditions using the reagent trifluoromethyl thianthrenium triflate (TTT). Chemical characterization and density functional theory calculations reveal that the trifluoromethyl groups bind covalently to surface chalcogen atoms as well as oxygen substitution sites. Trifluoromethylation induces p‐type doping in the underlying 2D material, enabling the modulation of charge transport and optical emission properties in WSe₂. This work introduces a versatile and efficient method for tailoring the optical and electronic properties of 2D transition metal dichalcogenides. 

Abstract A new approach to control the n‐doping reaction of organic semiconductors is reported using surface‐functionalized gold nanoparticles (f‐AuNPs) with alkylthiols acting as the catalyst only upon mild thermal activation. To demonstrate the versatility of this methodology, the reaction of the n‐type dopant precursor N‐DMBI‐H with several molecular and polymeric semiconductors at different temperatures with/without f‐AuNPs, vis‐à‐vis the unfunctionalized catalyst AuNPs, was investigated by spectroscopic, morphological, charge transport, and kinetic measurements as well as, computationally, the thermodynamic of catalyst activation. The combined experimental and theoretical data demonstrate that while f‐AuNPs is inactive at room temperature both in solution and in the solid state, catalyst activation occurs rapidly at mild temperatures (~70 °C) and the doping reaction completes in few seconds affording large electrical conductivities (~10–140 S cm⁻¹). The implementation of this methodology enables the use of semiconductor+dopant+catalyst solutions and will broaden the use of the corresponding n‐doped films in opto‐electronic devices such as thin‐film transistors, electrochemical transistors, solar cells, and thermoelectrics well as guide the design of new catalysts.