minimize the use of harmful chemicals in soil. Nanotechnology is a new technique
that has shown potential to enhance agricultural production without causing any
damage to the environment (Ditta 2012; Chinnamuthu and Boopati 2017; Elemike
et al. 2019). Nanotechnology has been implemented in developing fertilizers using
nanomaterials that improve the fertility and productivity of soil to a significant level
(Tarafdar et al. 2012a; Prasad et al. 2014). High catalytic reactivity, charge density,
surface area, strength, increased heat resistance, distinctive size and shape, magnetism because of large surface-to-volume ratio are some of the properties of
nanomaterials that contribute to development of nanofertilizers that help in improving nutritional content of the soil and hence the agricultural output. Nanoparticles in
the range of 1–100 nm possess high biological activity (Kandasamy and Prema
2015).
Nanofertilizers (Nfs) developed from nanomaterials provide nutrients to plants.
Nanoparticles possess large surface area and particle size less than the pore size of
root and leaves of the plant. Hence use of nanofertilizer increases the penetration of
nutrients into the plant and improves nutrient use efficiency. Small particles size (less
than 100 nm) facilitates penetration of nanoparticles in the plant from soil or leaf
surface. Nanofertilizers help in improving growth of plants via release of nutrients at
a slow rate. The fertilizer formulations prepared from nanomaterials increase uptake
of nutrients by minimizing nutrient loss in plant cells. High volume-to-surface ratio
of nanomaterial increases their efficiency to be used as fertilizer.
Nanofertilizers include various types such as nanoscale supplements
(nanoparticles having nutrients), nanoscale additives, and fertilizers with
nanoparticles coating (Khot et al. 2012). A mixture of more than one type of
nanomaterial has been used to develop nanocomposites (Liu et al. 2006).
Gamma irradiation, chemical reduction, photochemical and biological methods
are used in the preparation of nanoparticles which are used in the synthesis of
nanofertilizers (Remya et al. 2017). Nanoparticles used in the preparation of
nanofertilizers include TiO2 nanoparticles (Ti-NPs), carbon nanotubes (CNTs),
zeolites, etc. Techniques such as polymerization, emulsification, oxido-reduction,
ionic gelation, etc. have been applied for the synthesis of nanofertilizers.
Zeolites possess a honeycomb-like layered crystal structure which contains a
network of interconnected tunnels and cages laden with elements such as nitrogen,
potassium, phosphorous, calcium, and trace nutrients. They help in the slow release
of nutrients. Amendment of soil with zeolite lowers nitrate (NO 3
À ) and ammonium
(NH 4
+
) concentration but increases moisture retention due to increase in cation
exchange capacity (CEC) and nitrification. Zeolite has also been considered as a
carrier of nitrogen and potassium fertilizers (Selva and Balakrishna 2017). Carbon
nanotubes (CNT) are allotropes of carbon with cylindrical shape and are used to
deliver desired nutrients to plants (Wang et al. 2012a, b; Tiwari et al. 2014).
Nanofertilizers release nutrients slowly over a period of time (Giroto et al. 2017).
Nanoparticles degrade and release nutrients in the acidic or alkaline conditions of
water. Slight increase in temperature promotes release of nutrients. Nanofertilizer
particles facilitate slow and steady release of nutrients (Tarafdar et al. 2012a).
Enclosure of nutrients inside nanoporous materials coated with thin polymer film
230
B. Dhir
that has shown potential to enhance agricultural production without causing any
damage to the environment (Ditta 2012; Chinnamuthu and Boopati 2017; Elemike
et al. 2019). Nanotechnology has been implemented in developing fertilizers using
nanomaterials that improve the fertility and productivity of soil to a significant level
(Tarafdar et al. 2012a; Prasad et al. 2014). High catalytic reactivity, charge density,
surface area, strength, increased heat resistance, distinctive size and shape, magnetism because of large surface-to-volume ratio are some of the properties of
nanomaterials that contribute to development of nanofertilizers that help in improving nutritional content of the soil and hence the agricultural output. Nanoparticles in
the range of 1–100 nm possess high biological activity (Kandasamy and Prema
2015).
Nanofertilizers (Nfs) developed from nanomaterials provide nutrients to plants.
Nanoparticles possess large surface area and particle size less than the pore size of
root and leaves of the plant. Hence use of nanofertilizer increases the penetration of
nutrients into the plant and improves nutrient use efficiency. Small particles size (less
than 100 nm) facilitates penetration of nanoparticles in the plant from soil or leaf
surface. Nanofertilizers help in improving growth of plants via release of nutrients at
a slow rate. The fertilizer formulations prepared from nanomaterials increase uptake
of nutrients by minimizing nutrient loss in plant cells. High volume-to-surface ratio
of nanomaterial increases their efficiency to be used as fertilizer.
Nanofertilizers include various types such as nanoscale supplements
(nanoparticles having nutrients), nanoscale additives, and fertilizers with
nanoparticles coating (Khot et al. 2012). A mixture of more than one type of
nanomaterial has been used to develop nanocomposites (Liu et al. 2006).
Gamma irradiation, chemical reduction, photochemical and biological methods
are used in the preparation of nanoparticles which are used in the synthesis of
nanofertilizers (Remya et al. 2017). Nanoparticles used in the preparation of
nanofertilizers include TiO2 nanoparticles (Ti-NPs), carbon nanotubes (CNTs),
zeolites, etc. Techniques such as polymerization, emulsification, oxido-reduction,
ionic gelation, etc. have been applied for the synthesis of nanofertilizers.
Zeolites possess a honeycomb-like layered crystal structure which contains a
network of interconnected tunnels and cages laden with elements such as nitrogen,
potassium, phosphorous, calcium, and trace nutrients. They help in the slow release
of nutrients. Amendment of soil with zeolite lowers nitrate (NO 3
À ) and ammonium
(NH 4
+
) concentration but increases moisture retention due to increase in cation
exchange capacity (CEC) and nitrification. Zeolite has also been considered as a
carrier of nitrogen and potassium fertilizers (Selva and Balakrishna 2017). Carbon
nanotubes (CNT) are allotropes of carbon with cylindrical shape and are used to
deliver desired nutrients to plants (Wang et al. 2012a, b; Tiwari et al. 2014).
Nanofertilizers release nutrients slowly over a period of time (Giroto et al. 2017).
Nanoparticles degrade and release nutrients in the acidic or alkaline conditions of
water. Slight increase in temperature promotes release of nutrients. Nanofertilizer
particles facilitate slow and steady release of nutrients (Tarafdar et al. 2012a).
Enclosure of nutrients inside nanoporous materials coated with thin polymer film
230
B. Dhir