Bioinspired Ultralight Inorganic Aerogel for Highly Efficient Air Filtration and Oil–Water Separation

Abstract

Inorganic aerogels have been attracting great interest owing to their distinctive structures and properties. However, the practical applications of inorganic aerogels are greatly restricted by their high brittleness and high fabrication cost. Herein, inspired by the cancellous bone, we have developed a novel kind of hydroxyapatite (HAP) nanowire-based inorganic aerogel with excellent elasticity, which is highly porous (porosity ≈ 99.7%), ultralight (density 8.54 mg/cm, which is about 0.854% of water density), and highly adiabatic (thermal conductivity 0.0387 W/m·K). Significantly, the as-prepared HAP nanowire aerogel can be used as the highly efficient air filter with high PM filtration efficiency. In addition, the HAP nanowire aerogel is also an ideal candidate for continuous oil-water separation, which can be used as a smart switch to separate oil from water continuously. Compared with organic aerogels, the as-prepared HAP nanowire aerogel is biocompatible, environmentally friendly, and low-cost. Moreover, the synthetic method reported in this work can be scaled up for large-scale production of HAP nanowires, free from the use of organic solvents. Therefore, the as-prepared new kind of HAP nanowire aerogel is promising for the applications in various fields.

Recent Progress of Polysaccharide‐Based Hydrogel Interfaces for Wound Healing and Tissue Engineering

“…Therefore, the chitosan/PGA/alginate composite hydrogel could be synthesized through polyelectrolyte complex (PEC) interaction, in which alginate can improve the structure stability of the hydrogels, and PGA increase the hydrophilic and swelling properties of hydrogel. Besides, Jin et al explored a new method of semidissolution/acidification/sol–gel transition (SD‐A‐SGT) process for synthesizing PEC composite hydrogels . Chitosan power was evenly dispersed in solution to form a homogeneous composite structure hydrogel by exposing to a gaseous acidic atmosphere.…”

<p>Engineering of Aerogel-Based Biomaterials for Biomedical Applications</p>

“…[63][64][65] These HA nanowires and microtubes have been further manufactured into various materials with different structures, including ordered structures and aerogel structures. [66][67][68][69] For example, to mimic the microstructures of cancellous bone, Zhang et al 69 applied a new strategy to prepare ultralight HA nanowire aerogels with 3D-interconnected and porous meshwork microstructure ( Figure 5). The HA nanowire aerogels presented an ultrahigh porosity (∼99.7%), ultralow density (8.54 mg/cm 3 ), and high elasticity.…”

Free-Standing Sodium Titanate Ultralong Nanotube Membrane with Oil-Water Separation, Self-Cleaning, and Photocatalysis Properties

“…Gravity driven oil/water separation has been achieved by many hydrophobic or hydrophilic membranes contained one-dimensional components [37][38][39][40]. Therefore, the modified F-60 membrane with hydrophobicity was firstly used for the separation of immiscible oil/water mixtures.…”