Transparent and durable PDMS(O)/HDTMS anti-icing surfaces derived from candle soot

Preventing icing on exposed surfaces is important in our daily life. However, the transparent and durable anti-icing coating is still a challenge. In this work, we demonstrated a transparent oxidized polydimethylsiloxane/hexadecyltrimethoxysilane (PDMS(O)/HDTMS) coating on slide by using the candle soot (CS) as a sacrificial template. The CS as a product of incomplete combustion of candles with a porous network chain structure was firstly deposited on the PDMS coated slide. After a calcination treatment, the CS was removed while the PDMS layer was oxidized and inherited the unique structure of the CS and became transparent and superhydrophilic. With the help of the HDTMS modification, the final PDMS(O)/HDTMS coating exhibited surperhydrophobic property (WCA = 163°, SA < 1°). The coating can preserve its surperhydrophobic state after different mechanical abrasion, acid/base, UV light exposure and icing/thawing cycles. Beneficial from its surperhydrophobic feature, the coating not only postponed the freezing time of the water droplet from 229 to 1022 s, but also enabled the ice slide away by gravity. In addition, the PDMS(O)/HDTMS was successfully used on the glass insulator to delay the ice accumulation. This work provides a facile and environmentally-friendly method to obtain transparent and durable anti-icing coating.