Enhanced hydrogen production of PbTe-PbS/TNAs electrodes modified with ordered mesoporous carbon.

Abstract PbTe-PbS/TiO 2 nanotube arrays (PbTe-PbS/TNAs) were synthesized by the successive ionic layer adsorption and reaction (SILAR) followed by linear sweep voltammetry (LSV). Using Nafion as a binder, ordered mesoporous carbon was cast on these materials to generate the modified electrodes OMC/PbTe-PbS/TNAs. It was demonstrated that the electrode modification with OMC could enhance the charge transfer between the electrode surface and the electrolyte solution, improve the energy band bending of the electrode/electrolyte interface, increase the active electrochemical surface area of the electrode, and reduce the overpotential of the electrode reactions. Under ambient conditions, the short circuit current density (37.84 mA cm − 2 ) and the active electrochemical surface area (29 mF cm − 2 ) of the OMC/PbTe-PbS/TNAs electrode were 27.49% and 36.79% higher than that of PbTe-PbS/TNAs (29.68 mA cm − 2 and 21.2 mF cm − 2 ), respectively. A particularly important feature of the OMC modification is that the hot electron extraction capability of the PbTe-PbS/TNAs electrode remained in the new system to provide rapid enhancement of short circuit current density upon increasing temperature. The OMC/PbTe-PbS/TNAs electrode registered a hydrogen generation rate of 11 mL cm 2  h − 1 , with an energy efficiency of 98.79% and a heat efficiency of 43.03% under cell voltage of 1.0 V at 55 °C.