The quickly emerging smart home is heavily involved with various information technologies where electronic devices play perhaps the most important roles. However, there is currently a strong lack of an efficient tool for the direct manufacture of electronics as desired. Meanwhile, although printed electronics has aroused much attention in making printed circuit board, radio frequency identification card, sensor and so on, few existing approaches can fulfill the above needs. Among various technologies, liquid metal spraying method owns rather unique merits in printing electronically conductive patterns on nearly all kinds of substrates, either hard or soft, rough or smooth. For this reason, we are dedicated here to extend such method into a generalized strategy of printing electronics for the direct construction of smart home appliances which would generate profound influence on future daily lives. Through adopting the room temperature liquid metal GaIn_24.5 as the electronic ink and with various designed masks, a group of typical conductive patterns were directly printed on the surfaces of organic glass, marble windowsill, paper, wood plank of cabinet, building wall and so on, which consist of the most popular materials that could serve as circuit substrates in a home. It was shown that this energy-saving printing method brings about big convenience for equipping future smart home residents. Several new conceptual homemade printed patterns or circuits in providing services such as decoration and entertainment were illustrated. Further, the basic electronic structures of the smart home and the generalized concept of adopting any substrate surface as printed circuit board were explained. The liquid metal spray printing suggests a powerful tool for making consumer electronics and constructing future smart home. It also raised important scientific and technical issues worth of pursuing in the coming time.

ECS Journal of Solid State Science and Technology, 2015