中文摘要：

有为燃料房间的好耐久性和低费用的高度活跃的 electrocatalysts 的准备是高度合乎需要的，但是仍然是重要挑战。这里，我们综合了二维(2D ) C ₃ N ₄ nanosheets 支持了钯 composites (C ₃ 经由一条简单、方便的 sonochemical 途径的 N ₄/Pd) 。我们系统地学习了同样准备的催化剂的 electrocatalytic 表演。我们发现准备 C ₃ N ₄/Pd composites 在碱的媒介为氧减小反应(ORR ) 拥有了优秀催化活动和稳定性。鼓励地， C ₃ N ₄/Pd 催化剂在碱的媒介为甲醇氧化反应(粗腐殖质) 展出优秀 electrocatalytic 活动，比商业 Pt/C 催化剂的甚至好。2D C ₃ N ₄ nanosheets 与大表面区域和钯 nanoparticles 的优秀分散从他们在 ultrathin 底层材料之间的协同作用效果支持了钯 composites 催化剂结果。这研究证明那个 sonochemical 方法为燃料房间为 electrocatalysts 的准备开创一条新大街。我们期望这些材料是可能的发现例如，在大量应用的使用造成房间，太阳能电池，电池和另外的电气化学的分析。

英文摘要：

The preparation of highly active electrocatalysts with good durability and low cost for fuel cells is highly desir- able but still remains a significant challenge. Here we synthesized two dimensional （2D） C3N4 nanosheets supported palladium composites （C3N4/Pd） via a simple and convenient sonochemical approach. We have systematically stud- ied the electrocatalytic performance of as-prepared catalysts. We found that the prepared C3N4/Pd composites pos- sessed excellent catalytic activity and stability for oxygen reduction reaction （ORR） in alkaline media. Encourag- ingly, the C3N4/Pd catalysts exhibit the excellent electrocatalytic activity for methanol oxidation reaction （MOR） in alkaline media, even better than that of the commercial Pt/C catalyst, The excellent electrocatalytic performance of the 2D C3N4 nanosheets supported palladium composites catalysts results from their synergy effect between the ul- trathin substrate material with large surface area and excellent dispersion of palladium nanoparticles. This study demonstrates that sonochemical method opens up a new avenue for the preparation of electrocatalysts for fuel cells. We expect these materials are likely to find uses in a broad range of applications, for example, fuel cells, solar cells, batteries and other electrochemical analysis.