Nickel Doping in Atomically Thin Tin Disulfide Nanosheets Enables Highly Efficient CO₂ Reduction.

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Elemental doping is a key strategy for tuning catalyst electronic properties.
• Efficient electrocatalysts are crucial for carbon dioxide (CO₂) electroreduction.
• Atomically thin tin disulfide (SnS₂) nanosheets show potential for CO₂ electroreduction.

Purpose of the Study:

• To investigate the effect of nickel (Ni) doping on the CO₂ electroreduction performance of SnS₂ nanosheets.
• To understand the mechanism behind the enhanced catalytic activity.

Main Methods:

• Synthesis of Ni-doped SnS₂ nanosheets.
• Electrochemical characterization of CO₂ electroreduction.
• Mechanistic studies involving defect level and work function analysis.

Main Results:

• Ni doping significantly enhanced current density and Faradaic efficiency for carbonaceous products compared to pristine SnS₂.
• 5 atm% Ni-doped SnS₂ nanosheets achieved 93% Faradaic efficiency and 19.6 mA cm⁻² current density at -0.9 V vs. RHE.
• Ni doping introduced a defect level and lowered the work function of SnS₂ nanosheets.

Conclusions:

• Ni doping effectively promotes CO₂ activation and electroreduction on SnS₂ nanosheets.
• The modified electronic structure due to Ni doping is responsible for the improved catalytic performance.
• This work presents a viable strategy for designing advanced electrocatalysts for CO₂ conversion.