To study the effect of temperature on AgNPs synthesis, reactionmixtures
containing 20.0mL ALE, and 0.010 MAgNO3 were incubated at 20,
40 and 60 °C. The colors of the reaction mixtures, shown in Fig. 3, were
dark brown, orange and light brown. With the temperature increasing,
the color of silver colloid became dark gradually. The reaction temperaturewas
an important factorwhich affected the reaction kinetics.When
the preparation was carried out at 20 °C, the AgNPs formed, indicating
that some reduction from Ag+ to Ag0 occurred. However, comparing
with the products prepared at 60 °C indicates that the reaction was
slowat 20 °C.When the preparation was carried out at 80 °C, the products
had no significant change, indicating that almost reduction from
Ag+ to Ag0 occurred. The main reason was that atoms held higher kinetic
energy at higher temperature which led to high moving speed. The opportunities
of multiple collisions were increased which could contribute
to the nucleation growth of AgNPs