Development and applications of atmospheric pressure particle atomic layer deposition

Atmospheric pressure particle atomic layer deposition (AP-PALD) shows promising potentials in the fields of energy and catalytic materials due to its capability in precisely modifying the surfaces of functional materials operated at atmospheric or near-atmospheric pressure. This technique eliminates the usage of vacuum system, resulting in saving the costs of equipment and maintenance, and thereby exhibits great advantages in scale-up solutions. This paper reviews the fundamentals of self-terminating surface reactions on particles via ALD, challenges needing to be overcome, and pros and cons of AP-PALD. Then, the conformality of ALD has been overviewed briefly, followed by the development of reactor designs for temporal ALD (t-ALD) and spatial ALD (s-ALD) operated at atmospheric pressure together with the comparison about processing of high-throughput particles using t-ALD and s-ALD. Also, the applications of AP-PALD used in catalytic materials, drug delivery, Li-ion batteries, and etc. have been summarized. Finally, the perspectives of AP-PALD have been addressed.