1.D.112.  The Carbon-Nitride Nanotube Membrane (CN-NT) Family 

Biological light-driven ion pumps move ions against a concentration gradient to create a membrane potential, thus converting sunlight energy directly into an osmotic potential. Xiao et al. 2019 described an artificial light-driven ion pump system in which a carbon nitride nanotube membrane drives ions thermodynamically uphill against an up to 5000-fold concentration gradient by illumination. The separation of electrons and holes in the membrane under illumination results in a transmembrane potential which is thought to be the foundation for the pumping phenomenon. When used for harvesting solar energy, a sustained open circuit voltage of 550 mV and a current density of 2.4 muA/cm2 can reliably be generated, which can be further scaled up through series and parallel circuits of multiple membranes. The ion transport based photovoltaic system proposed offers a roadmap for the development of devices by using simple, cheap, and stable polymeric carbon nitride (Xiao et al. 2019).



Xiao, K., L. Chen, R. Chen, T. Heil, S.D.C. Lemus, F. Fan, L. Wen, L. Jiang, and M. Antonietti. (2019). Artificial light-driven ion pump for photoelectric energy conversion. Nat Commun 10: 74.