Fig. 1: Structural design, morphology, and liquid directional transport performance of PHT Janus membrane.

a The porosity gradient and liquid transport channels within plant leaves achieve water transport and vapor diffusion through the complex pore structures between the upper and lower epidermis, palisade tissue, and spongy layer. This multi-layered pore structure supports longitudinal water transport (from roots to leaves) and enables horizontal distribution through transverse pores, ensuring water balance for plants in arid environments. b Schematic diagram of the biomimetic structure of the PHT-Janus membrane, utilizing longitudinal channels and a horizontally interconnected pore network to construct efficient liquid directional transport pathways. The horizontally interconnected pore network is constructed as a buffer-absorbing layer of helical nanofibers. c SEM image showing the spongy structure of the HINF membrane, forming horizontally interconnected channels similar to the palisade tissue and spongy layer. d The whole cross-section of the PHT Janus membrane. e The magnified cross-section of the PAN hydrophobic layer and the cross-section of the TPU hydrophilic layer. f Photograph of the PHT-X Janus fiber membrane fabricated using electrospinning technology. Water content on the top and bottom surfaces when water droplets are placed on the top surface of the PHT-1 Janus fiber membrane in two water transportation modes: hydrophobic-to-hydrophilic mode (g) and hydrophilic-to-hydrophobic mode (h), with the inset showing water distribution maps (blue indicates wet, white indicates dry). i The diffusion behavior of water droplets on the hydrophobic and hydrophilic sides shows that when on the hydrophobic side, water can penetrate through the fiber membrane and spread on the hydrophilic side; however, on the hydrophilic side, wsater droplets only spread on the surface, while the hydrophobic side remains dry.