Wang Guanzhi, Yang Zhenzhong, Du Yingge, Yang Yang
NanoScience Technology Center, Department of Materials Science and Engineering, Energy Conversion and Propulsion Cluster, University of Central Florida, Orlando, FL, 32826, USA.
Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99352, USA.
Angew Chem Int Ed Engl. 2019 Oct 28;58(44):15848-15854. doi: 10.1002/anie.201907322. Epub 2019 Sep 20.
To produce efficient ORR catalysts with low Pt content, PtNi porous films (PFs) with sufficiently exposed Pt active sites were designed by an approach combining electrochemical bottom-up (electrodeposition) and top-down (anodization) processes. The dynamic oxygen-bubble template (DOBT) programmably controlled by a square-wave potential was used to tune the catalyst morphology and expose Pt active facets in PtNi PFs. Surface-bounded species, such as hydroxyl (OH , *=surface site) on the exposed PtNi PFs surfaces were adjusted by the applied anodic voltage, further affecting the dynamic oxygen (O ) bubbles adsorption on Pt. As a result, PtNi PF with enriched Pt(111) facets (denoted as Pt Ni PF) was obtained, showing prominent ORR activity with an onset potential of 0.92 V (vs. RHE) at an ultra-low Pt loading (0.015 mg cm ).
为了制备低铂含量的高效氧还原反应（ORR）催化剂，通过将电化学自下而上（电沉积）和自上而下（阳极氧化）过程相结合的方法，设计了具有充分暴露的铂活性位点的铂镍多孔膜（PFs）。由方波电位可编程控制的动态氧气泡模板（DOBT）用于调节催化剂形态并在铂镍PFs中暴露铂活性面。通过施加的阳极电压调节暴露的铂镍PFs表面上的表面结合物种，如羟基（OH，* =表面位点），进一步影响动态氧（O）气泡在铂上的吸附。结果，获得了富含Pt(111)面的铂镍PF（表示为Pt Ni PF），在超低铂负载量（0.015 mg cm）下显示出突出的ORR活性，起始电位为0.92 V（相对于可逆氢电极，RHE）。
