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Metal–organic framework (MOF)-derived catalysts are widely used for CO2 electroreduction to formate. However, the effect of the local coordination environment of MOF precursors on CO2 electroreduction activity is still unclear. Herein, Pb-MOF precursors with different coordination environments were synthesized by electrodeposition (Pb-MOF-e) and hydrothermal (Pb-MOF-t) methods, respectively. The coordination environment in Pb-MOF-t has eight O sites of benzene-1,3,5-tricarboxylate (BTC) ligands and one O site from H2O, while Pb-MOF-e has seven O sites of BTC ligands and two O sites from H2O. Pb-MOF-e and Pb-MOF-t could be derived into 4 and 70 nm particles on Pb and carbon paper (CP), and the catalysts are named Pb NP-e/Pb, Pb NP-e/CP, and Pb NP-t/CP. In particular, Pb NP-e/Pb exhibited higher formate selectivity (92.0%), with a maximum formate formation rate of 2734.5 μmol cm–1 h–1 at −2.4 V (vs Ag/Ag+), which is 4.7 and 5.8 times higher than that Pb NP-e/CP and Pb NP-t/CP. The experimental results showed that Pb-MOF-e has evolved structurally to form Pb nanoparticles with large an electrochemically active surface area, low interfacial transport resistance, and low adsorption potential of CO2·– intermediates. In addition, the edge of Pb nanoparticles as the active site could efficiently stabilize the *OCHO intermediate and enhance the activity. The obtained Pb NP-e/Pb catalyst shows promising prospects in CO2 electroreduction applications. [ABSTRACT FROM AUTHOR]

Uncontrolled hemorrhage, especially in non-compressible and deep wounds, remains a critical issue in emergency and surgical care. Existing hemostatic powders often lack rapid gelation, mechanical robustness, and adequate adherence, increasing the risk of rebleeding under high-pressure blood flow. To address these limitations, PQPP, a novel self-gelling hemostatic material composed of polyacrylamide/quaternized chitosan coacervates and polydopamine nanoparticles is developed. PQPP can rapidly absorb blood within 2 s, undergoes in situ gelation, and forms a robust adhesive hydrogel to effectively seal wounds. Its efficacy stems from the electrostatic adsorption and catechol functional groups of polydopamine nanoparticles. Importantly, PQPP exhibits high burst pressure resistance, excellent blood cell aggregation capability, outstanding biocompatibility, and antibacterial properties. Comprehensive in vitro and in vivo studies, including cytotoxicity and blood compatibility tests, as well as trials in mouse liver, heart, and vascular injury models, demonstrate PQPP's superior hemostatic performance under high-pressure conditions without causing inflammation. With its rapid gelation, robust adhesion, and mechanical integrity, PQPP represents a promising hemostatic material for immediate wound management in surgical and emergency applications., (© 2024 Wiley‐VCH GmbH.)