title: Copper-Organic Framework Fabricated with CuS Nanoparticles: Synthesis, Electrical Conductivity, and Electrocatalytic Activities for Oxygen Reduction Reaction.
abstract: To apply electrically nonconductive metal-organic frameworks (MOFs) in an electrocatalytic oxygen reduction reaction (ORR), we have developed a new method for fabricating various amounts of CuS nanoparticles (nano-CuS) in/on a 3D Cu-MOF, [Cu3(BTC)2⋅(H2O)3] (BTC=1,3,5-benzenetricarboxylate). As the amount of nano-CuS increases in the composite, the electrical conductivity increases exponentially by up to circa 109-fold, while porosity decreases, compared with that of the pristine Cu-MOF. The composites, nano-CuS(x wt %)@Cu-BTC, exhibit significantly higher electrocatalytic ORR activities than Cu-BTC or nano-CuS in an alkaline solution. The onset potential, electron transfer number, and kinetic current density increase when the electrical conductivity of the material increases but decrease when the material has a poor porosity, which shows that the two factors should be finely tuned by the amount of nano-CuS for ORR application. Of these materials, CuS(28 wt %)@Cu-BTC exhibits the best activity, showing the onset potential of 0.91 V vs. RHE, quasi-four-electron transfer pathway, and a kinetic current density of 11.3 mA cm-2at 0.55 V vs. RHE.
authors: Department of Chemistry, Hanyang University, Seoul, 04763, Republic of Korea.
authors: Keumnam
authors: K
authors: Cho
authors: Department of Chemistry, Hanyang University, Seoul, 04763, Republic of Korea.
authors: Sung-Hwan
authors: SH
authors: Han
authors: Department of Chemistry, Hanyang University, Seoul, 04763, Republic of Korea.|Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea.
authors: Myunghyun Paik
authors: 0000-0001-8325-752X
authors: MP
authors: Suh
keywords: copper sulfide; electrocatalysis; metal-organic frameworks; nanoparticles; oxygen reduction