Efficient photocatalytic hydrogen production by organic–inorganic heterojunction structure in Chl@Cu2O/Ti3C2Tx

The idea of exploiting the inexhaustible solar energy-driven photocatalytic hydrogen evolution reaction (HER) to generate hydrogen energy, a sustainable clean energy source, to solve problems such as fossil fuel-induced greenhouse gas emissions is believed to be a feasible strategy. However, photocatalytic HER is inefficient due to insufficient light trapping capability and low charge separation efficiency of the single semiconductor material employed. Therefore, it remains a great challenge to achieve fast and efficient photocatalytic HER. In this work, a novel ternary Chl@Cu2O/Ti3C2Tx photocatalyst with an organic–inorganic heterojunction structure has been designed by employing a stepwise deposition process for efficient solar energy conversion to hydrogen. The results showed that the photocatalytic activity of Chl@Cu2O/Ti3C2Tx organic–inorganic heterojunction photocatalysts for HER was significantly improved compared with that of single Chl@Ti3C2Tx and Cu2O/Ti3C2Tx. The improvement of the photocatalytic performance of Chl@Cu2O/Ti3C2Tx compared to Chl@Ti3C2Tx and Cu2O/Ti3C2Tx is attributed to the construction of the Chl–Cu2O organic–inorganic heterojunction structure in Chl@Cu2O/Ti3C2Tx, which extends the absorption range of the spectra and dramatically enhances the separation efficiency of the photogenerated carriers in Chl@Cu2O/Ti3C2Tx composites.