posted on 2024-02-08, 05:04authored byQing Huang, Juncheng Qi, Limin Zhou, Yao Wang, Wei-Xian Zhang, Jun Hu, Renzhong Tai, Shizhong Wang, Airong Liu, Lijuan Zhang
Gas nanobubbles used for water treatment and recovery
give rise
to great concern for their unique advantages of less byproducts, higher
efficiency, and environmental friendliness. Nanoscale zerovalent iron
(nZVI), which has also been widely explored in the field of environmental
remediation, can generate gas hydrogen by direct reaction with water.
Whether nanoscale hydrogen bubbles can be produced to enhance the
pollution removal of the nZVI system is one significant concern involved.
Herein, we report direct observations of in situ generation
of hydrogen nanobubbles (HNBs) from nZVI in water. More importantly,
the formed HNBs can enhance indeed the reduction of Se(IV) beyond
the chemical reduction ascribed to Fe(0), especially in the anaerobic
environment. The possible mechanism is that HNBs enhance the reducibility
of the system and promote electron transport in the solution. This
study demonstrates a unique function of HNBs combined with nZVI for
the pollutant removal and a new approach for in situ HNB generation for potential applications in the fields of in situ remediation agriculture, biotechnology, medical
treatment, health, etc.