氮摻雜中空多孔碳納米籠分級結(jié)構(gòu)在酸性和堿性條件下的氧還原行為

氮摻雜中空多孔碳納米籠分級結(jié)構(gòu)，特點(diǎn)有氮摻雜碳、中空結(jié)構(gòu)、富含空隙、微觀納米籠、分級結(jié)構(gòu)、具有在酸性環(huán)境和堿性環(huán)境條件下的良好氧還原活性。

離材料合成領(lǐng)域太久，這個(gè)反應(yīng)路徑好復(fù)雜，三個(gè)固體粉末混合在一起進(jìn)行熱解，感覺這個(gè)分級結(jié)構(gòu)是個(gè)固相反應(yīng)。

這種固相反應(yīng)產(chǎn)率和克級別生產(chǎn)難度會大一些。

The decomposition of ZIF－8 and transformation into 3D N－doped carbon at about 600 °C． The weight loss over 900 °C mainly resulted from the evaporation of Zn （b．p．907 °C）． The bottom－top gas flow produced by iron acetate decomposition can promote the expansion of micropores in ZIF－8 framework， resulting in a hollow hierarchical and pore structure．

不知道不同顆粒表面的XPS是否會有Zn和Fe，失重沒有那么徹底，穆譜的峰還挺明顯。0－0．08 wt．％的鐵連個(gè)XPS峰都沒有感覺這個(gè)體系還是有些復(fù)雜，可能有微觀局部相分離行為。

難能可貴的是酸性體系下的催化活性，雖然是氫氧反應(yīng)，但是能達(dá)到0．5A／cm2＠0．6V還是非常不容易。不知道長期運(yùn)行后的可能失效行為和雜原子是否會有關(guān)聯(lián)。

N－doped carbon electrocatalyst marked ORR activity in acidic media without the contribution by metal sites？

Fantao Kong， Xiangzhi Cui， Yifan Huang， Heliang Yao， Yafeng Chen， Han Tian， Ge Meng， Chang Chen， Ziwei Chang， Jianlin Shi

Abstract

Fe－N－C electrocatalysts have been demonstrated to be the most promising substitutes for benchmark Pt／C for oxygen reduction reaction （ORR）． Herein， we report that， a N－doped carbon materials with trace amount of iron （0－0．08 wt．％） show excellent ORR activity and durability comparable and even superior to those of Pt／C in both alkaline and acidic media without the significant contribution by the metal sites． Such a N－doped carbon （denoted as N－HPCs） features a hollow and hierarchically porous architecture， and more importantly， a non－covalent－bonded N－deficient／N－rich heterostructure providing the active sites for oxygen adsorption and activation owing to the efficient electron transfer between the layers． The primary Zn－air battery using N－HPCs as the cathode delivers a much higher power density of 158 mW cm－2， and the maximum power density in H2－O2 fuel cell reaches 486 mW cm－2， which is comparable to and even better than those using conventional Fe－N－C catalysts at cathodes．

原文標(biāo)題:氮摻雜中空多孔碳納米籠分級結(jié)構(gòu)在酸性和堿性條件下的氧還原行為