In recent years, there has been growing interest
in the varied applications of nanobubble
technology. Given their unique physicochemical
properties, such as minuscule size (<
1 mm), surface charge, and high internal pressure,
nanobubbles (NB) could provide new
opportunities in the fields of environmental
engineering (including environmental
remediation, water treatment, aerobic fermentation,
anaerobic digestion, and algal biomass
production), and agriculture (including
agronomy, horticulture, aquaculture, aquaponics,
bioponics, and hydroponics). In addition,
applying NB-derived reactive oxygen
species (ROS) can inactivate pathogens in
water treatment, remove harmfulmicroorganisms
on food, and remove persistent organic pollutants from wastewater (removal efficacies > 60%). NB
technology can also maintain high aqueous phase dissolved oxygen levels compared to conventional aeration,
as demonstrated in hydroponics and intensive crop farming, where NB-treated water led to increases
in plant yields (10?40%). However, a concise and comprehensive source of information on the fundamental
mechanisms involving NB technology is lacking. As NB applications advance into the biological frontier,
thesemechanisms serve as critical knowledge areas toward understanding the NB?biomolecular and cellular
mechanisms of action. In addition, mass transfer performance is not stringently assessed. To advance
and summarize current understanding, this review provides an updated, in-depth discussion of the fundamental
mechanisms and performance of NB technologies for various applications in environmental and
agricultural fields.Mechanistic details focusing on electrostatic and hydrophobic attachment, the formation
of ROS, and gas?liquid mass transfer are discussed. This review further outlines the opportunities and challenges
and concludeswith important research needs in NB technology.