Ultralow‐loss Optical Waveguides through Balancing Deep‐Blue TADF and Orange Room Temperature Phosphorescence in Hybrid Antimony Halide MicrostructuresZhou, Bo; Qi, Zhenhong; Dai, Meiqi; Xing, Chang; Yan, Dongpeng
doi: 10.1002/anie.202309913pmid: 37574452
Harnessing the potential of thermally activated delayed fluorescence (TADF) and room temperature phosphorescence (RTP) is crucial for developing light‐emitting diodes (LEDs), lasers, sensors, and many others. However, effective strategies in this domain are still relatively scarce. This study presents a new approach to achieving highly efficient deep‐blue TADF (with a PLQY of 25 %) and low‐energy orange RTP (with a PLQY of 90 %) through the fabrication of lead‐free hybrid halides. This new class of monomeric and dimeric 0D antimony halides can be facilely synthesized using a bottom‐up solution process, requiring only a few seconds to minutes, which offer exceptional stability and nontoxicity. By leveraging the highly adaptable molecular arrangement and crystal packing modes, the hybrid antimony halides demonstrate the ability to self‐assemble into regular 1D microrod and 2D microplate morphologies. This self‐assembly is facilitated by multiple non‐covalent interactions between the inorganic cores and organic shells. Notably, these microstructures exhibit outstanding polarized luminescence and function as low‐dimensional optical waveguides with remarkably low optical‐loss coefficients. Therefore, this work not only presents a pioneering demonstration of deep‐blue TADF in hybrid antimony halides, but also introduces 1D and 2D micro/nanostructures that hold promising potential for applications in white LEDs and low‐dimensional photonic systems.
Electroreductive Desulfurative Transformations with Thioethers as Alkyl Radical Precursors**Kuzmin, Julius; Röckl, Johannes; Schwarz, Nils; Djossou, Jonas; Ahumada, Guillermo; Ahlquist, Mårten; Lundberg, Helena
doi: 10.1002/anie.202304272pmid: 37342889
Thioethers are highly prevalent functional groups in organic compounds of natural and synthetic origin but remain remarkably underexplored as starting materials in desulfurative transformations. As such, new synthetic methods are highly desirable to unlock the potential of the compound class. In this vein, electrochemistry is an ideal tool to enable new reactivity and selectivity under mild conditions. Herein, we demonstrate the efficient use of aryl alkyl thioethers as alkyl radical precursors in electroreductive transformations, along with mechanistic details. The transformations proceed with complete selectivity for C(sp3)−S bond cleavage, orthogonal to that of established transition metal‐catalyzed two‐electron routes. We showcase a hydrodesulfurization protocol with broad functional group tolerance, the first example of desulfurative C(sp3)−C(sp3) bond formation in Giese‐type cross‐coupling and the first protocol for electrocarboxylation of synthetic relevance with thioethers as starting materials. Finally, the compound class is shown to outcompete their well‐established sulfone analogues as alkyl radical precursors, demonstrating their synthetic potential for future desulfurative transformations in a one‐electron manifold.
Acidic Hydrogen Evolution Electrocatalysis at High‐Entropy Alloys Correlates with its Composition‐Dependent Potential of Zero ChargeKim, Moonjoo; Batsa Tetteh, Emmanuel; Krysiak, Olga A.; Savan, Alan; Xiao, Bin; Piotrowiak, Tobias Horst; Andronescu, Corina; Ludwig, Alfred; Dong Chung, Taek; Schuhmann, Wolfgang
doi: 10.1002/anie.202310069pmid: 37537136
The vast possibilities in the elemental combinations of high‐entropy alloys (HEAs) make it essential to discover activity descriptors for establishing rational electrocatalyst design principles. Despite the increasing attention on the potential of zero charge (PZC) of hydrogen evolution reaction (HER) electrocatalyst, neither the PZC of HEAs nor the impact of the PZC on the HER activity at HEAs has been described. Here, we use scanning electrochemical cell microscopy (SECCM) to determine the PZC and the HER activities of various elemental compositions of a Pt−Pd−Ru−Ir−Ag thin‐film HEA materials library (HEA‐ML) with high statistical reliability. Interestingly, the PZC of Pt−Pd−Ru−Ir−Ag is linearly correlated with its composition‐weighted average work function. The HER current density in acidic media positively correlates with the PZC, which can be explained by the preconcentration of H+ in the electrical double layer at potentials negative of the PZC.
Electrode/Electrolyte Synergy for Concerted Promotion of Electron and Proton Transfers toward Efficient Neutral Water OxidationHao, Yaming; Kang, Yikun; Wang, Shaoyan; Chen, Zhe; Lei, Can; Cao, Xueting; Chen, Lin; Li, Yefei; Liu, Zhipan; Gong, Ming
doi: 10.1002/anie.202303200pmid: 37278979
Neutral water oxidation is a crucial half‐reaction for various electrochemical applications requiring pH‐benign conditions. However, its sluggish kinetics with limited proton and electron transfer rates greatly impacts the overall energy efficiency. In this work, we created an electrode/electrolyte synergy strategy for simultaneously enhancing the proton and electron transfers at the interface toward highly efficient neutral water oxidation. The charge transfer was accelerated between the iridium oxide and in situ formed nickel oxyhydroxide on the electrode end. The proton transfer was expedited by the compact borate environment that originated from hierarchical fluoride/borate anions on the electrolyte end. These concerted promotions facilitated the proton‐coupled electron transfer (PCET) events. Due to the electrode/electrolyte synergy, Ir−O and Ir−OO− intermediates could be directly detected by in situ Raman spectroscopy, and the rate‐limiting step of Ir−O oxidation was determined. This synergy strategy can extend the scope of optimizing electrocatalytic activities toward more electrode/electrolyte combinations.
Boosting Zn Anode Utilization by Trace Iodine Ions in Organic‐Water Hybrid Electrolytes through Formation of Anion‐rich Adsorbing LayersZhou, Kang; Li, Zhi; Qiu, Xuan; Yu, Zhuo; Wang, Yonggang
doi: 10.1002/anie.202309594pmid: 37531265
Aqueous Zn batteries are attracting extensive attentions, but their application is still hindered by H2O‐induced Zn‐corrosion and hydrogen evolution reactions. Addition of organic solvents into aqueous electrolytes to limit the H2O activity is a promising solution, but at the cost of greatly reduced Zn anode kinetics. Here we propose a simple strategy for this challenge by adding 50 mM iodine ions into an organic‐water (1,2‐dimethoxyethane (DME)+water) hybrid electrolyte, which enables the electrolyte simultaneously owns the advantages of low H2O activity and accelerated Zn kinetics. We demonstrate that the DME breaks the H2O hydrogen‐bond network and exclude H2O from Zn2+ solvation shell. And the I− is firmly adsorbed on the Zn anode, reducing the Zn2+ de‐solvation barrier from 74.33 kJ mol−1 to 32.26 kJ mol−1 and inducing homogeneous nucleation behavior. With such electrolyte, the Zn//Zn symmetric cell exhibits a record high cycling lifetime (14.5 months) and achieves high Zn anode utilization (75.5 %). In particular, the Zn//VS2@SS full cell with the optimized electrolyte stably cycles for 170 cycles at a low N : P ratio (3.64). Even with the cathode mass‐loading of 16.7 mg cm−2, the full cell maintains the areal capacity of 0.96 mAh cm−2 after 1600 cycles.
Modular Functionalization of Metal‐Organic Frameworks for Nitrogen Recovery from Fresh Urine**Guo, Lei; Zhang, Yi; Osella, Silvio; Webb, Samuel M.; Yang, Xue‐Jing; Goddard, William A.; Hoffmann, Michael R.
doi: 10.1002/anie.202309258pmid: 37559432
Nitrogen recovery from wastewater represents a sustainable route to recycle reactive nitrogen (Nr). It can reduce the demand of producing Nr from the energy‐extensive Haber‐Bosch process and lower the risk of causing eutrophication simultaneously. In this aspect, source‐separated fresh urine is an ideal source for nitrogen recovery given its ubiquity and high nitrogen contents. However, current techniques for nitrogen recovery from fresh urine require high energy input and are of low efficiencies because the recovery target, urea, is a challenge to separate. In this work, we developed a novel fresh urine nitrogen recovery treatment process based on modular functionalized metal–organic frameworks (MOFs). Specifically, we employed three distinct modification methods to MOF‐808 and developed robust functional materials for urea hydrolysis, ammonium adsorption, and ammonia monitoring. By integrating these functional materials into our newly developed nitrogen recovery treatment process, we achieved an average of 75 % total nitrogen reduction and 45 % nitrogen recovery with a 30‐minute treatment of synthetic fresh urine. The nitrogen recovery process developed in this work can serve as a sustainable and efficient nutrient management that is suitable for decentralized wastewater treatment. This work also provides a new perspective of implementing versatile advanced materials for water and wastewater treatment.