Polymers producing hydrogen

Plasmonic Pt-PPCN/TiN Ohmic Junction for Photo-Thermo Catalytic Hydrogen Production

The rational design of photocatalysts for improving the conversion of solar energy into hydrogen is a promising route for achieving carbon neutrality. Herein, we couple plasmonic titanium nitride (TiN) with highly crystalline potassium-doped polymeric carbon nitride (PPCN) to construct a PPCN/TiN ohmic junction. Such an ohmic junction not only broadens the absorption spectrum but also inhibits the recombination of electrons and holes. In addition, Pt nanoparticles are introduced into this ohmic junction to form plasmonic Pt-PPCN/TiN, improving the capture of hot electrons generated by TiN and thereby promoting the dissociation of the O-H bond in H2O. The energy barrier decreases from 0.7 to 0.2 eV. Enhanced separation of carrier, activation of water molecules, and capture of hot electrons are jointly promoting photo-thermo catalytic hydrogen production. Therefore, under full-spectrum irradiation, the hydrogen production rate of Pt-PPCN/TiN reaches 19 085 μmol g-1 h-1. This novel plasmonic photocatalyst is promising for full-spectrum photo-thermo catalytic hydrogen production.

Synergetic Photo-Thermo Catalytic Hydrogen Production by Carbon Materials

Photo-thermo catalytic hydrogen production represents one of the most promising routes for channeling solar energy but typically suffers from high reaction temperatures. In this work, we develop photo-thermo catalytic hydrogen production at low temperatures by cost-effective, nonplasmonic, and metal-free nitrogen-doped carbon materials (CNO_1-x). We demonstrate that due to the photothermal conversion of CNO_1-x, carrier generation is improved and electron migration is enhanced to suppress the recombination of electron-hole pairs, both of which promote hydrogen production by photocatalysis, while generated hydrogen radicals facilitate the regeneration of active sites for hydrogen production by thermocatalysis. Such synergy greatly promotes photo-thermo catalytic hydrogen production at low temperatures. These results demonstrate the great promise of photo-thermo catalytic hydrogen production over carbon materials at low temperatures.