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Metallic heterostructural nanocrystals (HNCs) hold immense potential in electrocatalytic carbon dioxide reduction reaction (CO2RR) owing to their abundant active sites and high intrinsic activity. However, a significant challenge still remains in achieving controlled nucleation and growth sites for HNCs on supports and comprehending the influence of the structure–activity relationship on electrocatalytic CO2RR performance. This work presents a photochemical self-assembly technique without the necessity for reducing agents or facet-specific capping agents. By controlling lattice mismatch and manipulating transfer paths of photo-generated carriers, we can precisely direct the growth sites and nucleation of nanocrystals, enabling the self-assembly of supported core–shell and Janus nanostructures. Compared to Pd(T)@Au core–shell HNCs with the same loading, Pd cube–Au Janus HNCs exhibit significantly enhanced selectivity and stability toward carbon monoxide (CO) production in CO2RR at less negative potentials. The Pd cube–Au Janus HNC electrocatalyst achieved a Faradaic efficiency (FE) of 92.6 ± 3.5% for CO electroreduction, accompanied by a current density of 72.3 mA·cm−2 at −0.58 V. This work provides an effective strategy for designing advanced supported tandem electrocatalysts to boost the selectivity and durability test of CO2RR. [ABSTRACT FROM AUTHOR]

The electrochemical reduction of CO or CO2 into C2+ products has mostly been focused on Cu‐based catalysts. Although Ag has also been predicted as a possible catalyst for the CO‐to‐C2+ conversion from the thermodynamic point of view, however, due to its weak CO binding strength, CO rapidly desorbs from the Ag surface rather than participates in deep reduction. In this work, we demonstrate that single‐atomic Pd sites doped in Ag lattice can tune the CO adsorption behavior and promote the deep reduction of CO toward C2 products. The monodispersed Pd−Agn sites enable the CO adsorption with both Pd‐atop (PdL) and Pd−Ag bridge (PdAgB) configurations, which can increase the CO coverage and reduce the C−C coupling energy barrier. Under room temperature and ambient pressure, the Pd1Ag10 alloy catalyst exhibited a total CO‐to‐C2 Faradaic efficiency of ~37 % at −0.83 V, with appreciable current densities and electrochemical stability, thus featuring unconventional non‐Cu electrocatalytic CO‐to‐C2 conversion capability. [ABSTRACT FROM AUTHOR]

Summary: Background: Esophagogastroduodenoscopy (EGD) is required to screen for high‐risk varices (HRV) in patients with hepatocellular carcinoma (HCC), especially since overall survival rates have dramatically improved with new systemic therapies. Aim: To assess the Baveno VI and Baveno VII algorithms' ability to rule out HRV in hepatitis B virus (HBV)‐related HCC Methods: We prospectively enrolled consecutive patients with HBV related, compensated cirrhosis and newly diagnosed HCC who underwent liver stiffness measurement, spleen stiffness measurement (SSM) using a 100‐Hz shear wave frequency, and EGD. Results: From September 2021 to August 2023, we enrolled 219 patients with HCC, with 107 (48.9%) Barcelona Clinic Liver Cancer (BCLC) A, 28 (12.8%) BCLC B and 84 (38.3%) BCLC C, respectively. HRV prevalence was 28.8% (63/219). Baveno VI criteria safely (HRV missing rate, 3.2%) avoided 27.4% unnecessary EGDs, while the Baveno VII algorithm avoided 49.3% with HRV missing rate at 7.9% (5/63). The SSM ≤40 kPa avoided 47.5% of EGDs safely (HRV missing rate, 4.8%), significantly better than the Baveno VI criteria (p < 0.001) and comparable to the Baveno VII algorithm (p = 0.390). The SSM ≤40 kPa safely avoided EGDs in patient subgroups within Milan criteria, with portal vein tumour thrombosis or BCLC B/C or candidates for systemic therapy. Conclusions: We validated that the SSM ≤40 kPa using a 100‐Hz probe could safely eliminate more unnecessary EGDs than the Baveno VI criteria in patients with HBV‐related HCC. However, the efficacy of the Baveno VII algorithm in patients with HCC requires further investigation. [ABSTRACT FROM AUTHOR]

Photocatalysis is an important technique for synthetic transformations. However, little attention has been paid to light‐driven synergistic redox reactions for directed synthesis. Herein, the authors report tunable oxidation of benzyl to phenylcarbinol with the modest yield (47%) in 5 h via singlet oxygen (1O2) and proton‐coupled electron transfer (PCET) over the photocatalyst Zn0.5Cd0.5S (ZCS)/graphene oxide (GO) under exceptionally mild conditions. Theoretical calculations indicate that the presence of S vacancies on the surface of ZCS/GO photocatalyst is crucial for the adsorption and activation of O2, successively generating the superoxide radical (•O2−) and 1O2, attributing to the regulation of local electron density on the surface of ZCS/GO and photogenerated holes (h+). Meanwhile, accelerated transfer of photogenerated electrons (e−) to GO caused by the π–π stacking effect is conducive to the subsequent aldehyde hydrogenation to benzyl alcohol rather than non‐selective oxidation of aldehyde to carboxylic acid. Anisotropic charge transport driven by the built‐in electric field can further promote the separation of e− and h+ for multistep reactions. Promisingly, one‐pot photocatalytic conversion of p‐xylene to 4‐methylbenzyl alcohol is beneficial for reducing the harmful effects of aromatics on human health. Furthermore, this study provides novel insights into the design of photocatalysts for cascade reactions. [ABSTRACT FROM AUTHOR]