Graphene oxide carbon nanomaterial for sustainable agriculture: Synthesis, soil health, nutrient management and saline water remediation

The increasing demand for sustainable agricultural production, coupled with declining soil health, inefficient nutrient use and poor irrigation water quality, necessitates the development of innovative and eco-friendly technologies. Among the nanomaterials, two-dimensional graphene oxide (GO) has gained attention due to their extraordinary physical and chemical properties, including high specific surface area, a better number of oxygen-containing functional groups, high adsorption capacity and surface chemistry. Green synthesis approaches using biomass, agricultural residues and plant extracts are highlighted for their potential to reduce environmental impacts and promote sustainable nanomaterial production. This review further discusses advanced characterisation methods such as Fourier transform infrared spectroscopy, x-ray diffraction pattern, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, Brunauer–Emmett–Teller surface area analysis and x-ray photoelectron spectroscopy for understanding their structure and function. These analytical techniques provide critical insights into the structural attributes that determine the agricultural performance of GO nanomaterials. Soil–nanomaterial interactions, adsorption of nutrients, controlled release of nutrients and removal of sodium ions from saline irrigation water were thoroughly assessed. Based on existing evidence, application of GO may enhance soil aggregation, water holding capacity, nutrient utilisation efficiency and irrigation water quality and help sustain crop production. However, challenges related to large-scale production, long-term environmental fate, biosafety, economic viability and regulatory standardisation have hindered widespread adoption in agriculture. Future research should prioritise scalable and cost-effective production technologies, long-term field validation, standardised risk assessment protocols and integration with precision agriculture to facilitate commercial adoption.