Pd Single‐Atom‐Doped Cu ₃ Co Quantum Dots With Optimized Hydrogenation Kinetics for Versatile Aluminum‐Nitrate Primary Battery With Synchronous Energy Harvesting and Waste Valorization

ABSTRACT The rational design of nitrate batteries enabling simultaneous electricity generation and pollutant degradation is highly promising, yet most reported systems, such as Zn‐nitrate or aldehyde‐nitrate batteries, face critical limitations, including sluggish cathodic nitrate reduction kinetics, high anode material cost, low‐value anode reaction products, inferior open‐circuit potential (OCP), and limited power output. Optimizing catalyst activity and NH 3 selectivity via structure‐activity relationships is pivotal to enhancing the electrical output efficiency of such batteries. Herein, we report a Pd single‐atom‐doped Cu 3 Co quantum dots electrocatalyst (Pd sa ‐Cu 3 Co QDs), which modulates H* adsorption to accelerate the key hydrogenation steps of NO 3 RR, achieving a positive onset of +0.18 V (vs. RHE) and nearly 100% Faradaic efficiency (FE) for NH 3 at −0.5 V (vs. RHE). A novel Al‐NO 3 − primary battery is further constructed by coupling cathodic NO 3 RR with anodic aluminum oxidation, enabling cathodic NH 3 production and anodic conversion of waste aluminum (e.g., used Cola cans) to green H 2 and high‐value alums. This battery exhibits an OCP of 1.26 V, 8.85 mW cm −2 peak power density, and an FE of 48.78% NH 3 , 56.88% H 2 , and yield 56.10% alum, significantly enhancing its economic viability and practical application.