Heterogeneous catalysts are complex materials with multiple interfaces. A critical proposition in exploiting bifunctionality in alloy catalysts is to achieve surface migration across interfaces separating functionally dissimilar regions. Herein, we demonstrate the enhancement of more than 10 4 in the rate of molecular hydrogen reduction of a silver surface oxide in the presence of palladium oxide compared to pure silver oxide resulting from the transfer of atomic hydrogen from palladium oxide islands onto the surrounding surface formed from oxidation of a palladium-silver alloy. The palladium-silver interface also dynamically restructures during reduction, resulting in silver-palladium intermixing. This study clearly demonstrates the migration of reaction intermediates and catalyst material across surface interfacial boundaries in alloys with a significant effect on surface reactivity, having broad implications for the catalytic function of bimetallic materials.

A template-assisted synthetic method including the thermal polycondensation of guanidine hydrochloride (GndCl) was utilized to synthesize highly-organized mesoporous graphitic carbon nitride (mpg-C 3 N 4) photocatalysts. Comprehensive structural analysis of the mpg-C 3 N 4 materials were performed by XPS, XRD, FT-IR, BET and solid-state NMR spectroscopy. Photocatalytic performance of the mpg-C 3 N 4 materials was studied for the photodegradation of several dyes under visible and UV light illumination as a function of catalyst loading and the structure of mpg-C 3 N 4 depending on the polycondensation temperature. Among all of the formerly reported performances in the literature (including the ones for Degussa P25 commercial benchmark), currently synthesized mpg-C 3 N 4 photocatalysts exhibit a significantly superior visible light-induced photocatalytic activity towards rhodamine B (RhB) dye. Enhanced catalytic efficiency could be mainly attributed to the terminated polycondensation process, high specific surface area, and mesoporous structure with a wide pore size distribution. Keywords Graphitic-C 3 N 4 Á Carbon nitride Á UV-Vis light Á Photocatalytic degradation Á Organic dyes Electronic supplementary material The online version of this article (

Pd is auto-oxidized during deposition onto AgOx and undergoes a transition from single to bi-layer growth at low Pd coverage.