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Achieving precise control over the site-selective production of deuterium-labeled alkenes under mild conditions is highly appealing. However, it is crucial to determine how to use a green chemical process and an economical deuterium source to achieve this goal. In this paper, Pd nanoparticles supported on N-doped porous carbon (Pd0.05-NC) on the cathode for the electrocatalytic semideuteration reaction of alkynes with D2O. The reaction exhibits a high selectivity of 96% and a Faradaic efficiency (FE) of 74.9% under low voltage conditions. Mechanistic studies highlight the importance of adsorption of alkynes and the activation of D2O on the Pd0.05-NC cathode surface to achieve highly selective and efficient synthesis. The capture of key deuterium and carbon radicals confirms the existence of the reactive D species addition pathway and cross-coupling of free radicals. The gram-scale synthesis of deuterated alkenes in a continuous-flow electrolyzer and the wide range of substrates highlight their promising applications. [ABSTRACT FROM AUTHOR]

The slower kinetics of the deuterium evolution reaction (DER) than the hydrogen evolution reaction (HER) renders conventional Pt-based HER catalysts inefficient in the DER. Their further improvement requires precise tuning of intermediate adsorption energy which is already near optimum on pure Pt. Herein, we achieved superior DER/HER performance by combining Pt and a dual support system consisting of V2O3 and V8C7 that exert different electronic effects on Pt. In 1 M NaOD (NaOH) and 0.5 M D2SO4 (H2SO4), the optimal Pt/V2O3/V8C7 catalyst exhibited low overpotentials of 37 mV (15 mV) and 49 mV (45 mV) at a current density of 10 mA cm−2, respectively. Its mass activity based on the amount of Pt was up to 9 times higher than that of commercial Pt/C, leading to a reduction of cell voltage by 0.5 V in PEM electrolysis of D2O at 1000 mA cm−2. X-ray photoelectron spectroscopy and underpotential H deposition showed that electron-withdrawing effects of V2O3 over-weakened intermediate adsorption on Pt/V2O3 while Pt/V8C7 had insufficient metal–support interaction of such kind. A balanced effect was only achieved with the dual support system, which accounts for the excellent performance of Pt/V2O3/V8C7. This study provides a new perspective on the modulation of metal–support interaction in Pt-based electrocatalysts and demonstrates potential application of the Pt/V2O3/V8C7 in industrial production of D2. [ABSTRACT FROM AUTHOR]

Compared to the hydrogen evolution reaction (HER), the deuterium evolution reaction (DER) has slower kinetics that causes unsatisfactory performance of conventional HER catalysts in DER. Herein, we report a Ni/V2O3‐500 catalyst with nanosheet morphology that shows excellent performance in both alkaline DER and HER with ultralow overpotential of 64 mV (in 1 M NaOD) and 32 mV (in 1 M NaOH) at 10 mA cm−2. The activity remains stable after accelerated durability test and 1000 h of chronopotentiometric test at 500 mA cm−2. The high performance is attributed to uniform dispersion of Ni nanoparticles and synergistic effects between Ni and V2O3. Density functional theory modeling demonstrates that the synergistic effect optimizes the adsorption of H*/D* intermediate, promoting the reaction rate. This study provides valuable insights into metal‐support interactions in electrocatalysis which facilitates the development of superior DER/HER catalysts. The Ni/V2O3‐500 shows great potential for industrial applications. [ABSTRACT FROM AUTHOR]

The high energy barrier of D–O bond breakage leads to a slow kinetic reaction rate in the electrocatalytic deuterium evolution reaction (DER). Therefore, the platinum–carbon catalyst (Pt/C) shows unsatisfactory performance in the DER. Here, Pt/B4C catalysts were constructed via the strong metal support interaction (SMSI) between boron carbide (B4C) and platinum (Pt). The SMSI influenced the electronic structure and dispersion of Pt, resulting in a higher degree of Pt dispersion on B4C with stronger electronegativity, and Pt/B4C thus exhibited better DER/HER performance than Pt/C in acidic and basic solutions. The overpotential was only 48 mV (11 mV) and 47 mV (31 mV) when the current density was 10 mA cm−2 in 1 M NaOD (NaOH) and 0.5 M D2SO4 (H2SO4), respectively. The Pt/B4C catalyst activity showed no decay after accelerated durability testing (ADT) and 100 hours of i–t stability testing. Density functional theory (DFT) suggests that the electron rearrangement between B4C and metallic Pt leads to a stronger electronegativity of Pt, whereas the electron-deficient state of Pt can facilitate the dissociation of D2O/H2O and the resolution of D2/H2. This research provides a useful new guideline and reference for the preparation of high-performance DER/HER catalysts. [ABSTRACT FROM AUTHOR]

In the process of the optical interconnection module soldering assembly, the mismatch of the thermal expansion coefficient between the substrate and printed circuit board would result in the production of alignment offset between light source devices and light-coupled devices, which would lead to light power loss. It is of great significance to study the optical interconnect module alignment offset in the assembly process to improve the optical interconnect module coupling efficiency. In this paper, an optical interconnection module key position postsoldering shift offset measurement system was established, and an optical interconnection module experimental sample was prepared. The key position postsoldering shift in the $x$ - and $y$ -directions was measured. The 3-D finite-element analysis model of a typical optical interconnect module was established, and postsoldering shift offsets were calculated after the finite-element analysis of the optical interconnect module under reflow soldering temperature load. The coupling efficiency simulation model of the optical interconnection module was established using the ZEMAX software, and the coupling efficiency was calculated according to the alignment offset measured in the experiment. The results revealed the following: the postsoldering alignment offsets in the $x$ - and $y$ - directions were 0.316 and 0.422 $\mu \text{m}$ , respectively, and the synthetic alignment offset was $0.527~\mu \text{m}$. The postsoldering alignment offset calculated using the finite-element simulation model was $0.436~\mu \text{m}$ , and its error was 17.2%, when compared with the measured value. The coupling efficiency of the optical interconnection module was 85.804% when the postsoldering alignment offset was $0.527~\mu \text{m}$. [ABSTRACT FROM AUTHOR]