Nanoscale non-biochar formulations of banana peel layers for comparison of in vitro adsorption and release of ammonium with demonstration of fertilizing action

The convergent ability of non-biochar biomass-formulations to adsorb and release NH<inf>4</inf>⁺ has not been extensively investigated. In this work, we have prepared nanoscale non-biochar formulations of banana peel sections and studied their ability to adsorb and release NH<inf>4</inf>⁺. A combination of FTIR, XRD, FESEM, EDX, TGA, DTG, BET and DLS highlight the distinctive nanoscale structural, surface and thermal properties of the banana peel formulations. The inner and outer sections of banana peel display attractive surface porosity and superlative adsorption efficiencies towards NH<inf>4</inf>⁺ that are superior compared to reported biomass-derived NH<inf>4</inf>⁺ adsorbents. The nanoscale banana peel adsorbents display quantitative in vitro release of adsorbed NH<inf>4</inf>⁺. The direct treatment of Arabidopsis thaliana with NH<inf>4</inf>⁺ loaded banana peel adsorbents result in significant and distinctive enhancements in leaf area, root number, and root length. The nanoscale non-biochar banana peel formulations reported in this work hold promise as eco-friendly and cost-effective adsorbents and fertilizers.