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Net-zero carbon strategies and green synthesis methodologies are key to realizing the United Nations’ sustainable development goals (SDGs) on a global scale. An electrocatalytic glycerol oxidation reaction (GOR) holds the promise of upcycling excess glycerol from biodiesel production directly into precious hydrocarbon commodities that are worth orders of magnitude more than the glycerol feedstock. Despite years of research on the GOR, the synthesis process of nanoscale electrocatalysts still involves (1) prohibitive heat input, (2) expensive vacuum chambers, and (3) emission of toxic liquid pollutants. In this paper, these knowledge gaps are closed via developing a laser-assisted nanomaterial preparation (LANP) process to fabricate bimetallic nanocatalysts (1) at room temperature, (2) under an ambient atmosphere, and (3) without liquid waste emission. Specifically, PdCu nanoparticles with adjustable Pd:Cu content supported on few-layer graphene can be prepared using this one-step LANP method with performance that can rival state-of-the-art GOR catalysts. Beyond exhibiting high GOR activity, the LANP-fabricated PdCu/C nanomaterials with an optimized Pd:Cu ratio further deliver an exclusive product selectivity of up to 99% for partially oxidized C3 products with value over 280000-folds that of glycerol. Through DFT calculations and in situ XAS experiments, the synergy between Pd and Cu is found to be responsible for the stability under GOR conditions and preference for C3 products of LANP PdCu. This dry LANP method is envisioned to afford sustainable production of multimetallic nanoparticles in a continuous fashion as efficient electrocatalysts for other redox reactions with intricate proton-coupled electron transfer steps that are central to the widespread deployment of renewable energy schemes and carbon-neutral technologies.

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Polymer-oxide semiconductor exhibits a promising application on electronic devices. In this study, zinc oxide-polyaniline (ZnO-PAni) junctions were constructed which showed a photodiode-like behavior. The junctions were built through connecting the electrodeposited zinc oxide to electrodeposited HCl-doped polyaniline. Without illumination, the junctions exemplify a diode-like behavior (e.g., large amount current at forward-bias while small amount of current at reverse-bias). When illuminated, the junctions exhibit a photodiode-like behavior. In such, the reverse-bias current increases with light intensity.