Rapid, High‐Temperature, In Situ Microwave Synthesis of Bulk Nanocatalysts

Abstract

Carbon‐black‐supported nanoparticles (CNPs) have attracted considerable attention for their intriguing catalytic properties and promising applications. The traditional liquid synthesis of CNPs commonly involves demanding operation conditions and complex pre‐ or post‐treatments, which are time consuming and energy inefficient. Herein, a rapid, scalable, and universal strategy is reported to synthesize highly dispersed metal nanoparticles embedded in a carbon matrix via microwave irradiation of carbon black with preloaded precursors. By optimizing the amount of carbon black, the microwave absorption is dramatically improved while the thermal dissipation is effectively controlled, leading to a rapid temperature increase in carbon black, ramping to 1270 K in just 6 s. The whole synthesis process requires no capping agents or surfactants, nor tedious pre‐ or post‐treatments of carbon black, showing tremendous potential for mass production. As a proof of concept, the synthesis of ultrafine Ru nanoparticles (≈2.57 nm) uniformly embedded in carbon black using this microwave heating technique is demonstrated, which displays remarkable electrocatalytic performance when used as the cathode in a Li–O2 battery. This microwave heating method can be extended to the synthesis of other nanoparticles, thereby providing a general methodology for the mass production of carbon‐supported catalytic nanoparticles.

Scalable Synthesis of High Entropy Alloy Nanoparticles by Microwave Heating

“…Microwave heating is an effective way to induce thermal energy and has been used for the synthesis of organic and high-quality carbon materials, − as well as carbon-loaded nanomaterials. − We demonstrate in this work the use of microwave heating for the rapid and facile synthesis of HEA-NPs, as illustrated in Figure . The partially reduced graphene oxide film in argon at ∼570 K (named rGO-570 film) is employed as a model substrate.…”

Critical advances in re-engineering the cathode-electrolyte interface in alkali metal-oxygen batteries

“…Some noble and transition metal nanoparticles have also shown their capability in improving the OER performance [80] . For example, there have been published methods of loading Ru on modified graphene oxide or carbon black [81][82][83] . Batteries using these materials could be charged below 4 V. Some researchers have also devoted their attention to gel electrolytes.…”

Non-thermal radiation heating synthesis of nanomaterials

“…Consequently, the metal NPs, including Ru, Pd, and Ir with a uniform size of~20 nm, were synthesized successfully, confirming the universal synthesis of NPs by MH. Moreover, Zhong et al [56] synthesized Ru, Pt, Pd, and Au NPs loaded on a carbon black matrix by MH. Taking Ru as a demonstration, a certain amount of commercial carbon black was first immersed in Ru 3+ solution, followed by freeze-drying to obtain a solid mixture.…”