Fig. 4: Microstructural and compositional analysis of CIOHMs with varying CA contents.

A Transmission electron microscopy (TEM) images illustrating the internal microstructures of CIOHMs at various CA contents (absent, 0.6%, and 1.2%, wt%) (Independent experiments were repeated no less than three times). CaP nanoclusters are indicated by yellow arrows. Scale bar: 200 nm. B High-resolution transmission electron microscopy (HRTEM) images and Energy-dispersive X-ray spectroscopy (EDS) elemental mappings illustrating the internal microstructures of 0.6%CA-CIOHM (Independent experiments were repeated no less than three times). CaP nanoclusters are indicated by yellow arrows. Scale bar: 50 nm (HRTEM) and 100 nm (EDS). Purple dots: C element. Blue dots: Ca element. Yellow dots: N element. Red dots: O element. Green dots: P element. C Scanning electron microscopy (SEM) images showing the surface morphology of CIOHMs in both the ground and hydration states (Independent experiments were repeated no less than three times). The presence of pores formed during hydration is denoted by yellow arrows. Scale bar: 10 µm. D Energy-dispersive X-ray spectroscopy (EDS) elemental mapping of CIOHMs, illustrating the distribution of constituent elements in both the ground and hydration states. Yellow dots: Ca element. Purple dots: P element. Red dots: C element. Green dots: N element. Blue dots: O element. E Thermogravimetric (TG) alongside differential thermal analysis (DTA) curves for CIOHMs with different CA contents (absent, 0.6%, and 1.2%, wt%). The TG lines are represented in black, while the DTA results are indicated in blue.