Nanobiochar for the remediation of contaminated soil and water: challenges and opportunities

Abstract

Although research on biochar has received increasing attention for environmental and agricultural applications, the significance of nanobiochar for environmental pollutant  remediation is poorly understood. In contrast to bulk biochar, nanobiochar has superior physicochemical properties such as high catalytic activity, unique nanostructure, large specific surface area and high mobility in the soil environment. These unique characteristics make nanobiochar an ideal candidate for pollution remediation. Thus far, the research on nanobiochar is still in its infancy and most of the previous studies have only been  conducted for exploring its properties and environmental functions. The lack of in-depth summary of nanobiochar’s research direction makes it a challenge for scientists and researchers globally. Hence in this review, we established some key fabrication methods for nanobiochar with a focus on its performance for the removal of pollutants from the environment. We also provided up-to-date information on nanobiochar’s role in environmental remediation and insights into different mechanisms involved in the pollutant removal. Although, nanobiochar application is increasing, the associated drawbacks to the soil ecosystem have not received enough research attention. Therefore, further research is warranted to evaluate the potential environmental risks of nanobiochar before large scale application.

Highlight

•	Key synthesis technologies and properties of nanobiochars were discussed.
•	The interactions pathways of nanobiochar with pollutants were elucidated.
•	Role of environmental factors on pollutants remediation and life cycle was delineated.
•	Important research outlooks on nanobiochar’s potential in pollutant remediation were elaborated.

Funding

National Natural Science Foundation of China(42107245)

Postdoctoral Research Foundation of China(2021M701455)