CSIR Energy Materials, PO Box 395, Pretoria 0001, South Africa.
UNESCO-UNISA Africa Chair in Nanosciences/Nanotechnology, College of Science, Engineering and Technology, University of South Africa, Muckleneuk ridge, PO Box 392, Pretoria, South Africa; Nanosciences African Network (NANOAFNET), Materials Research Department, iThemba LABS-National Research Foundation of South Africa, Old Faure Road, PO Box 722, Somerset West 7129, Western Cape, South Africa.
J Colloid Interface Sci. 2019 Jun 1;545:138-152. doi: 10.1016/j.jcis.2019.03.030. Epub 2019 Mar 11.
Carbon dioxide (CO) is considered a useful greenhouse gas that can be captured and be used in the electro-syntheses of useful chemicals or fuels. On the other hand, there's also a tremendous interest on ethanol beneficiation as it is largely produced from crops, and it is regarded as a potential candidate for low temperature fuel cell applications. Although ethanol possesses good advantages, its resistant to oxidation poses a threat. The main objective of the study is to synthesis bio-inspired metal oxide-support catalyst which will help enhance the activity, efficiency and selectivity of Pd catalyst in CO reduction, Fuel cell performance and ethanol oxidation. Here, Pd nanoparticles were supported on NiO/C through a green facile one-step process using pomegranate peel extracts as reducing agent. A series of characterizations were carried out to provide proof for and to quantify the presence of Pd, Ni, O and C in the prepared sample. Microscopic methods confirmed the successful preparation of pure NiO/C and (%5 Pd) Pd-NiO/C, evident by the key elemental components, mixed nanostructures and co-existence of Pd and NiO/C. The resultant Pd-NiO/C nanocatalyst revealed higher activity towards the oxidation of ethanol and that the nanocatalyst is more tolerant to poising by intermediate oxidation species. Enhanced cell performance with current and power densities of 66 mA cm and 26 mW cm relative to the commercial Pd/C were obtained under passive conditions at 1 M ethanol in 1MKOH. In addition, the nanocatalyst showed good selectivity to HCOOH with enhanced current efficiencies of 45%.
二氧化碳（CO）被认为是一种有用的温室气体，可以被捕获并用于电合成有用的化学品或燃料。另一方面，人们对乙醇的提纯也非常感兴趣，因为它主要是由农作物生产的，被认为是低温燃料电池应用的潜在候选物。虽然乙醇具有良好的优势，但它的抗氧化性是一个威胁。本研究的主要目的是合成生物启发的金属氧化物载体催化剂，这将有助于提高 Pd 催化剂在 CO 还原、燃料电池性能和乙醇氧化中的活性、效率和选择性。在这里，通过使用石榴皮提取物作为还原剂的绿色简便一步法，将 Pd 纳米粒子负载在 NiO/C 上。进行了一系列的特性分析，以提供和量化所制备样品中 Pd、Ni、O 和 C 的存在。微观方法证实了纯 NiO/C 和 (%5 Pd) Pd-NiO/C 的成功制备，这是由关键元素成分、混合纳米结构和 Pd 和 NiO/C 的共存所证明的。所得的 Pd-NiO/C 纳米催化剂对乙醇的氧化表现出更高的活性，并且纳米催化剂对中间氧化物种的中毒更具耐受性。在 1MKOH 中 1M 乙醇的被动条件下，与商业 Pd/C 相比，获得了 66 mA cm 和 26 mW cm 的电流密度和功率密度，相对较高的电池性能。此外，纳米催化剂对 HCOOH 表现出良好的选择性，电流效率提高了 45%。
