In-situ green and batch ultrafast preparation of carbon nanotube-linked PdNi alloy nanoparticles for boosting oxygen reduction reaction

The high efficiency, low cost, and rapid preparation of non-noble metal oxygen reduction reaction (ORR) electrocatalysts are of great significance for the large-scale application of energy conversion equipment. Herein, PdNi alloy nanoparticles dispersed within the multiwalled carbon nanotubes (MWCNTs) composite (PdNi-PVP/MWCNTs) were synthesized via an in situ self-assembly strategy, in which polyvinylpyrrolidone (PVP) serves as an N and C source, and MWCNTs act as conducting supports to enhance structural integrity and electron transport. Notably, the synthesis relies solely on low-temperature oil-bath stirring, enabling rapid batch production without the need for high-temperature calcination-a distinctly green and scalable approach. In this system, PVP acts as a capping agent that facilitates the uniform anchoring of PdNi alloy nanoparticles on MWCNTs, effectively suppressing particle aggregation, thereby increasing the surface roughness and specific surface area to expose more active sites. Impressively, benefiting from the unique structure, high crosslinking, and high conductivity that minimize catalyst separation and aggregation, this new type of electrocatalyst exhibited an impressive ORR onset potential of 0.97 V, half-wave potential of 0.83 V, larger current density of 4.3 mA∙cm −2 , and existing good corrosion resistance to drive a relatively stable performance, which are superior to commercial Pt/C in alkaline media. This study demonstrates the successful design of an environmentally benign and cost-effective ORR electrocatalyst, highlighting its promising potential for practical applications in energy conversion technologies.