Clean silica surfaces have a high surface energy. In consequence, colliding silica nanoparticles will stick rather than bounce over a wide range of collision velocities. Often, however, silica surfaces are passivated by adsorbates, in particular water, which considerably reduce the surface energy. We study the effect of surface hydroxylation on silica nanoparticle collisions by atomistic simulation, using the REAX potential that allows for bond breaking and formation. We find that the bouncing velocity is reduced by more than an order of magnitude compared to clean nanoparticle collisions.

中文翻译：

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羟基氧化二氧化硅纳米粒子的弹跳：基于REAX势的原子研究。

清洁的二氧化硅表面具有较高的表面能。结果，碰撞的二氧化硅纳米颗粒将在大范围的碰撞速度下粘附而不是反弹。但是，二氧化硅表面经常被吸附剂，特别是水钝化，这大大降低了表面能。我们使用允许键断裂和形成的REAX电势，通过原子模拟研究了表面羟基化对二氧化硅纳米粒子碰撞的影响。我们发现与干净的纳米粒子碰撞相比，弹跳速度降低了一个数量级以上。