The paper presents the isolation and characterization of few-layer black phosphorus flakes using a modified mechanical exfoliation method, which yields higher yields of atomically thin flakes compared to conventional methods. The authors provide guidelines for determining the number of layers using optical microscopy, Raman spectroscopy, and transmission electron microscopy. They demonstrate that the exfoliated flakes are highly crystalline and stable, even in free-standing form. Density functional theory (DFT) calculations reveal a strong thickness dependence of the band structure, and exciton binding energy calculations confirm the optical bandgap. The environmental stability of the flakes is studied, showing that they are hydrophilic and susceptible to degradation in air moisture. Despite this, the aging process is slow enough to allow the fabrication of field-effect transistors with strong ambipolar behavior. The study highlights the potential of black phosphorus as a promising material for electronic devices.The paper presents the isolation and characterization of few-layer black phosphorus flakes using a modified mechanical exfoliation method, which yields higher yields of atomically thin flakes compared to conventional methods. The authors provide guidelines for determining the number of layers using optical microscopy, Raman spectroscopy, and transmission electron microscopy. They demonstrate that the exfoliated flakes are highly crystalline and stable, even in free-standing form. Density functional theory (DFT) calculations reveal a strong thickness dependence of the band structure, and exciton binding energy calculations confirm the optical bandgap. The environmental stability of the flakes is studied, showing that they are hydrophilic and susceptible to degradation in air moisture. Despite this, the aging process is slow enough to allow the fabrication of field-effect transistors with strong ambipolar behavior. The study highlights the potential of black phosphorus as a promising material for electronic devices.