ACS Nano 2024, 18, 10279?10287,https://doi.org/10.1021/acsnano.4c01386
Abstract:
Gradient-Janus wire (GJW) with a diameter of 0.3 mm has been fabricated
on a large scale through liquid confined modification, enabling the opposite conical wetting
phenomenon along the same orientation of the GJW, characterized by an increasing
superhydrophilic region and a decreasing hydrophobic region. This property allows the GJW
to exhibit controllable water hovering, transport, and pinning during fog harvesting, i.e., at a
large tilting angle α of 60° (mass increased with decreased α), the GJW can hover 0.6 mg of
harvested fogwater in 30 s, can transport 3 mg of fogwater along the gradient in 30 s at α =
4° (with maximal mass reaching up to 4.3 mg at α = ?10°), and finally, pin the water droplet
at the end of the GJW. Such ability generates an effective torque that serves as the driving
force for rotation. We designed a GJWs-wheel by radially arranging 60 GJWs together,
resulting in an extremely lightweight structure weighing only 1.9 g. The cumulative torque
generated during fog harvesting activates the rotation of the GJWs-wheel. When loaded with
a coil within a magnetic field, electricity is generated as output power peaks at around 0.25
μW while maintaining a high water harvesting efficiency averaging approximately 38 ± 2.12 mg/min. This finding is significant
as it provides valuable insights into designing materials capable of efficiently harnessing both energy and water resources.