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Natural species use their surface structures for water harvesting. It is the dire need of the hour to learn from nature, mimic its functions, and solve the water scarcity problem through dew condensation. However, the present microscale and nanoscale approaches still suffer from complicated fabrication methods and durability failure in harsh conditions. Here, we introduce a bioinspired slippery surface of candle soot particles which uses its bumps to enhance the growth of condensed water droplets. The Namib desert beetles-inspired convex topography, cacti-inspired asymmetric slope, and Nepenthes pitcher plant-inspired slippery surface of soot particles synergistically combines the large droplet nucleation density, fast droplet coalescence, and easy removal of droplet from the surface. The hydrophilic SLIPS of soot particles harvests water at a rate of 326.4 ± 9 mg/cm2 h-1 which is 70 % high as compared to hydrophobic SLIPS of soot particles. The fluorinated SLIPS reveals 32 % high water collection rate as compared to the methyl-terminated SLIPS of candle soot particles and the results are corroborated by calculating the intermolecular hydrogen bonding energies through DFT. The programmed motion of water droplet on a slippery surface of soot particles is also observed by applying laser light, heat, and magnetic field even against gravity. The slippery surface shows long-term stability due to nano-porosity, permeation of lubricant into soot particles and lubricant's crosslinking ability with the binder. The developed surface is biocompatible, self-cleaning, and suitable for water harvesting particularly in cold and arid regions. [Display omitted] • Multi-bioinspired slippery asymmetric bumps of candle soot particles were fabricated. • Namib desert beetles-inspired topography helped to enhance the water condensation. • Cactus spines-inspired asymmetric slope of aggregated soot particles facilitate the directional motion of water. • Nepenthes pitcher plants-inspired slippery surface helped for easy removal of water droplet.. • Fluorinated SLIPS showed high water collection rate due to high electronegativity difference of C-F bond. [ABSTRACT FROM AUTHOR]

Electrocatalytic CO 2 reduction reaction (CO 2 RR) emerges as a promising avenue to mitigate carbon emissions, enabling the capture and conversion of CO 2 into high-value products such as syngas with CO/H 2 . One of the crucial aspects lies in the tailored development of durable and efficient electrocatalysts for the CO 2 RR. Covalent organic frameworks (COFs) possess unique characteristics that render them attractive candidates for catalytic applications. However, the relationship between structure and performance still requires further exploration; especially, most COFs with such properties are limited to COFs containing specific groups such as phthalocyanine or porphyrin groups. Here, we custom-synthesize two azine-linked nitrogen-rich COFs constructed from triazine building blocks, which are doped with ultrafine and highly dispersed Ag nanoparticles (Ag@TFPT-HZ and Ag@TPT-HZ). Thus-obtained COFs can serve as electrocatalysts for the CO 2 RR, and a comprehensive investigation has been conducted to uncover the intricate structure-performance relationship within these materials. Notably, Ag@TFPT-HZ exhibits superior CO selectivity in the electrocatalytic CO 2 RR, achieving a FE CO of 81% and a partial current density of 7.65 mA·cm -2 at the potential of -1.0 V (vs reversible hydrogen electrode (RHE)). In addition, Ag@TPT-HZ as an electrocatalyst can continuously produce syngas with a CO/H 2 molar ratio of 1:1, an ideal condition for methanol synthesis. The observed distinct performance between these two COFs is attributed to the presence of O atoms in TFPT-HZ. These O atoms facilitate a higher loading capacity of Ag nanoparticles (11 wt %) and generate a greater number of active sites, thereby enhancing electrochemical activity and promoting faster reaction kinetics. Therefore, two tailor-made two-dimensional (2D) nitrogen-rich COFs with various active sites as electrocatalysts can exhibit different outstanding electrocatalytic performances for CO 2 RR and possess high cycling stability (>50 h). This work offers valuable insights into the design and synthesis of electrocatalysts, particularly in elucidating the intricate relationship between their structure and performance.