PtCu Alloy-Modified Triptycene-Based Polymer with Charge Separation for Photocatalytic Hydrogen Evolution from Water/Seawater

Direct photocatalytic hydrogen from earth-abundant seawater is a great potential way to achieve sustainable and clean energy, yet unsatisfactory decomposition and rapid electron-hole pair recombination of catalysts hinder the solar-driven H₂ conversion efficiency. Herein, we designed a series of PtCu alloy nanoparticle-modified porous triptycene-based polymers (Pt_xCu₁-TCP) to construct the heterostructure for highly efficient hydrogen generation from photocatalytic water/seawater splitting. Characterizations displayed that TCP with an ultrahigh surface area can confine the agglomeration of PtCu alloy; meanwhile, the PtCu alloy can facilitate the rapid electron transfer from TCP. In addition, TCP with a stable covalent bond structure can resist the corrosion of seawater. Benefiting from these two advantages, Pt₇Cu₁-TCP showed a remarkably enhanced photocatalytic performance with a maximum H₂ evolution rate of 3255 μmol g^-1 h^-1 in natural seawater with triethanolamine, which is 2.69, 116.25, and 1.08 times that of Pt-TCP, Cu-TCP, and optimal catalyst in pure water, respectively. This study provides an idea for the development of a novel catalytic system for hydrogen production from solar-driven water/seawater splitting.