Optimal deposition condition of chlorophyll a Langmuir–Blodgett film

The optimal deposition condition of chlorophyll a (Chl a) Langmuir–Blodgett (LB) film were investigated based on π–a isotherms, absorption spectrum and scanning tunneling microscopy (STM) observation. The π–a isotherms of Chl a LB film at various air temperatures and subphase pHs were obtained. Optimum temperature and pH for dense packing of Chl a LB layers are 25 °C and 7.0, respectively. The formation of J- and H-aggregations of the ordered chlorophyll a molecules was confirmed by absorption spectrum measurements. The well-ordered structure of Chl a LB layer was observed by STM. Thus, the densely packed Chl a LB layer could be fabricated by the proposed optimal deposition condition.