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The synthesis of highly monodispersed InAs colloidal quantum dots (CQDs) is needed in InAs CQD-based optoelectronic devices. Because of the complexities of working with arsenic precursors such as tris-trimethylsilyl arsine ((TMSi)3As) and tris-trimethylgermyl arsine ((TMGe)3As), several attempts have been made to identify new candidates for synthesis; yet, to date, only the aforementioned two highly reactive precursors have led to excellent photodetector device performance. We begin the present study by investigating the mechanism, finding that the use of the cosurfactant dioctylamine plays a crucial role in producing monodispersed InAs populations. Through quantitative analysis of ligands on the surface of InAs CQDs, we find that (TMGe)3As leads to In-rich characteristics, and we document the presence of an amorphous In-oleate shell on the surface. This we find causes surface defects, and thus, we develop materials processing strategies to remove the surface shell with a view to achieving efficient charge transfer in CQD solids. As a result, we develop resurfacing protocols, tailored to each dot synthesis, that produce balanced In-to-As stoichiometry regardless of synthetic input, enabling us to fabricate NIR photodetectors that achieve best-in-class EQEs at 940 nm excitons (25–28%, biased), independent of the synthetic pathway.

The electrochemical reduction of CO2in acidic conditions enables high single-pass carbon efficiency. However, the competing hydrogen evolution reaction reduces selectivity in the electrochemical reduction of CO2, a reaction in which the formation of CO, and its ensuing coupling, are each essential to achieving multicarbon (C2+) product formation. These two reactions rely on distinct catalyst properties that are difficult to achieve in a single catalyst. Here we report decoupling the CO2-to-C2+reaction into two steps, CO2-to-CO and CO-to-C2+, by deploying two distinct catalyst layers operating in tandem to achieve the desired transformation. The first catalyst, atomically dispersed cobalt phthalocyanine, reduces CO2to CO with high selectivity. This process increases local CO availability to enhance the C–C coupling step implemented on the second catalyst layer, which is a Cu nanocatalyst with a Cu–ionomer interface. The optimized tandem electrodes achieve 61% C2H4Faradaic efficiency and 82% C2+Faradaic efficiency at 800 mA cm−2at 25 °C. When optimized for single-pass utilization, the system reaches a single-pass carbon efficiency of 90 ± 3%, simultaneous with 55 ± 3% C2H4Faradaic efficiency and a total C2+Faradaic efficiency of 76 ± 2%, at 800 mA cm−2with a CO2flow rate of 2 ml min−1.

Potassium ion channels underlie vital biological functions such as heartbeat and muscle contraction. Recent studies investigating the interaction between potassium ion channels and terahertz waves suggest the potential of terahertz modulation in future disease treatments and neural regulation. This study employs molecular dynamics simulations to explore the interaction between terahertz electric fields and the Kv1.2 voltage-gated potassium ion channel. Results indicate that a 51.8-THz electric field induces carbonyl resonances in the selectivity filter (SF), accelerating potassium transmembrane movement and enhancing channel permeability. This field strengthens the SF’s ability to maintain its activated state, enhancing both its stability and functionality. Consequently, it provides a more stable and favorable pathway for potassium ions. This study offers a more in-depth theoretical elucidation regarding the modulation of ion channel behavior through terahertz electric fields.

Stable metal nitrides (MN) are promising materials to fit the future “green” ammonia–hydrogen nexus. Either through catalysis or chemical looping, the reductive hydrogenation of MN to MN1–xis a necessary step to generate ammonia. However, encumbered by the formation of kinetically stable M-NH1─3surface species, this reduction step remains challenging under mild conditions. Herein, we discovered that deleterious Ti-NH1─3accumulation on TiN can be circumvented photochemically with supported single atoms and clusters of platinum (Pt1-Ptn) under N2–H2conditions. The photochemistry of TiN selectively promoted Ti-NH formation, while Pt1-Ptneffectively transformed any formed Ti-NH into free ammonia. The generated ammonia was found to originate mainly from TiN reduction with a minor contribution from N2activation. The knowledge accrued from this fundamental study could serve as a springboard for the development of MN materials for more efficient ammonia production to potentially disrupt the century-old fossil-powered Haber–Bosch process.

Lead-free double perovskites offer non-toxic properties and strong emission via alloying and doping. Herein, we report the synthesis of Bi-doped pure Rb2HfCl6and Cs-alloyed RbCsHfCl6microcrystals. The pure Rb2HfCl6microcrystals are nearly non-emissive while alloying with Cs and Bi doping lead to strong deep blue emission at 466 nm with an increase in photoluminescence quantum yield from ∼0 to 66%. Density functional theory studies attest to the improved phase stability due to Cs-alloying and link photoluminescence to Bi3+dopant-induced localized states.

•The rice husk is decomposed into cellulose, lignin, and hemicellulose.•Comparative analysis of thermodynamic and kinetic models for biomass redox stages.•The CH4generated by pyrolysis reduces the error of Gibbs reaction model.•Various factors affecting gasification reaction are discussed based on the model.

Renewable-energy-powered electrosynthesis has the potential to contribute to decarbonizing the production of propylene glycol, a chemical that is used currently in the manufacture of polyesters and antifreeze and has a high carbon intensity. Unfortunately, to date, the electrooxidation of propylene under ambient conditions has suffered from a wide product distribution, leading to a low faradic efficiency toward the desired propylene glycol. We undertook mechanistic investigations and found that the reconstruction of Pd to PdO occurs, followed by hydroxide formation under anodic bias. The formation of this metastable hydroxide layer arrests the progressive dissolution of Pd in a locally acidic environment, increases the activity, and steers the reaction pathway toward propylene glycol. Rh-doped Pd further improves propylene glycol selectivity. Density functional theory (DFT) suggests that the Rh dopant lowers the energy associated with the production of the final intermediate in propylene glycol formation and renders the desorption step spontaneous, a concept consistent with experimental studies. We report a 75% faradic efficiency toward propylene glycol maintained over 100 h of operation.