Amorphous ZnSnO_x Hollow Spheres Enable Highly Efficient CO₂ Reduction.

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Carbon dioxide reduction reaction (CO2RR) is crucial for sustainable energy. Effective CO2RR electrocatalysts require efficient CO2 adsorption and rapid electron transport.
• Zinc tin oxide (ZSO) materials show promise for CO2RR, but their performance can be limited by structural and electronic properties.

Purpose of the Study:

• To develop a new class of diverse hollow ZSO materials with enhanced CO2 adsorption and electron transport properties.
• To investigate the effect of amorphization on the CO2RR performance of ZSO materials.
• To demonstrate the practical application of amorphous ZSO for efficient and stable CO2 reduction to HCOOH.

Main Methods:

• Amorphization of ZSO hydroxides via a calcination process.
• Characterization of amorphized ZSO using Fourier transform infrared spectroscopy and Raman spectra.
• Electrochemical evaluation of ZSO hollow spheres (ZSO HSs) for CO2RR, including Faradaic efficiency and stability tests.
• In-situ attenuated total reflectance infrared absorption spectroscopy to study CO2 adsorption and intermediate transformation.

Main Results:

• Amorphization of ZSO was confirmed by spectroscopic analysis.
• ZSO HSs achieved a high Faradaic efficiency (FE) of HCOOH up to 92.7%, outperforming commercial ZSO (85.7%).
• ZSO HSs demonstrated durable stability with negligible activity decay after 10 hours of electrolysis.
• In-situ spectroscopy revealed strong CO2 adsorption and rapid intermediate configuration transformation in amorphous ZSO HSs.

Conclusions:

• Amorphous ZSO hollow spheres are effective electrocatalysts for CO2 reduction reaction (CO2RR).
• The enhanced CO2 adsorption and electron transport in amorphous ZSO contribute to high HCOOH selectivity and stability.
• This work provides a new strategy for designing efficient CO2RR electrocatalysts through material amorphization.