Modulation of nanostructures provides great opportunities for improving surface states and therefore catalytic activities. In this regard, facile strategies for precise control on surface compositions or structures of nanocatalysts at atomic level are very important. In the past few years, we were devoted to exploration of aqueous conditions for the synthesis of bimetallic nanoicosahedra as catalysts for energy conversion. The specialties of bimetallic nanoicosahedra contain tunable electronic effects by turning compositions and surface tensile strain induced by twin defects. The two factors both result in large improvement of surface activities. In this talk, we are going to get insights into the stories of Pd-based bimetallic nanoicosahedra in aspects of their aqueous syntheses and applications for electric- and solar-to-chemical energy conversion. First of all, turning a halide switch to control the formation of AuPd nanoicosahedra in the alloy or core-shell structures will be introduced. In the comparison of their catalytic performances, it revealed that Au-Pd core-shell nanoicosahedra possessed better ability to utilize visible light energy via LSPR of Au nanophases in the photoreduction of 4-nitrophenol. Based on this kind of active core-shell structure, we modulated the surface AuPd compositions through controlling the ratios of Au and Pd precursors, and found out the best surface state for energy conversion was in a Au-Pd ratio of 55:45. In the last part of the talk, the stories of the unprecedented icosahedral PdRu nanoframes will be introduced. In the synthesis, the formation of nanoframes with a high surface-to-volume ratio was achieved due to a kinetic balance between growth and slow etching in the low pH environment. Moreover, the existence of Ru was able to assist in prevention the frame surfaces from CO poison.