# Intramolecular Synergy of CO2 Activation and H Spillover on Heteronuclear Dual‐Metal Phthalocyanine Assemblies for Selective CO2 Photoreduction

## TL;DR

A new photocatalyst efficiently converts CO2 into CO using sunlight, with high selectivity due to a unique dual-metal structure.

## Contribution

A dual-metal phthalocyanine assembly is shown to synergistically enhance CO2 activation and hydrogen spillover for selective CO2 photoreduction.

## Key findings

- CuNiPc/BiVO4 achieves 238 mmol gCu⁻¹ h⁻¹ CO yield with nearly 100% selectivity.
- The synergy between Cu–Ni dual sites enhances CO2 activation and protonation.
- Fast Z-scheme charge transfer and intramolecular H spillover improve performance.

## Abstract

Solar‐driven CO2 conversion holds great promise in carbon recycling. CO2 activation and hydrogen spillover are crucial for high‐selectivity CO2 reduction, while with great challenges. Here, heteronuclear metal phthalocyanine aggregates with atomically active sites are synthesized and then assembled on BiVO4 nanosheets. The CuNiPc/BiVO4 nanocomposite achieves a 238 mmol gCu
−1 h−1 CO yield with nearly 100% selectivity (vs 77% for mononuclear CuPc/BiVO4) without H2 evolution, ranking among top atomic‐engineered photocatalysts. Femtosecond‐transient absorption spectra, in situ synchrotron radiation measurements, and theoretical simulations, etc., reveal that such a difference is mainly ascribed to the fast interfacial Z‐scheme charge transfer kinetics and the synergy catalysis between dual sites in CuNiPc. The Cu–N4 moiety enhances CO2 adsorption and activation relative to CuPc due to the regulated Cu configuration caused by the Ni atom incorporation, while the adjacent Ni–N4 unit activates H2O to generate *H, which subsequently undergoes intramolecular spillover to *Cu–COO site, consequently accessing both CO2 activation and protonation for *COOH generation towards highly selective CO2 reduction.

The CuNiPc/BiVO4 heterojunction is designed and synthesized for selective CO2 photoreduction. The cascade interfacial Z‐scheme charge transfer and the intramolecular synergy of Cu–Ni dual sites on CO2 activation and H spillover contribute to the high photocatalytic performance and selectivity.