Fabrication of a novel Ni3N/Ni4N heterojunction as a non-noble metal co-catalyst to boost the H2 evolution efficiency of Zn0.5Cd0.5S. (12th February 2020)

• Record Type: Journal Article
• Authors: Jin, Zhanbin; Wei, Tingting; Li, Fengyan; Zhang, Qiu; Xu, Lin
• Is Part Of: New journal of chemistry. Volume 44:Number 8(2020)
• Page Start: 3471
• Page End: 3477
• Publication Date: 2020-02-12
• Subjects: Chemistry -- Periodicals; Chimie -- Périodiques; 540
• DOI: 10.1039/c9nj06429j
• Languages: English
• ISSNs: 1144-0546

Abstract

Abstract : Ni x N/Zn0.5 Cd0.5 S composites displayed better photocatalytic hydrogen production from water in comparison with pristine Zn0.5 Cd0.5 S (ZCS), as well as Pt/ZCS and Ni3 N/ZCS. Abstract : Previous studies have shown that auxiliary catalysts play a significant role in improving the activity and reliability of semiconductor photocatalysis for photocatalytic H2 production. However, designing an efficient and low-cost auxiliary catalyst to replace expensive noble metals has been a major challenge. In our study, we synthesized a non-noble metal co-catalyst Ni3 N/Ni4 N (Ni x N) by a two-step method. Upon loading 2% Ni x N on Zn0.5 Cd0.5 S (ZCS), the photocatalytic activity of 2% Ni x N/ZCS greatly improved. The corresponding H2 evolution rate was about 241.3 mmol h −1 g −1, which was obtained in 0.35 M Na2 S/0.25 M Na2 SO3 . This value is about 33 times higher than that of pure ZCS, 12 times higher than that of 2% Pt on ZCS and 3 times higher than that of 2% Ni3 N/ZCS. When the concentration of Na2 S/Na2 SO3 was increased to 1.05 M/0.75 M, the H2 production rate of 2% Ni x N/ZCS reached 297.6 mmol h −1 g −1 under visible light irradiation ( λ > 420 nm), and the quantum efficiency (QE) was 43.8% at 420 nm. The H2 production efficiency of 2% Ni x N/ZCS is the highest H2 evolution efficiency among ZCS-based photocatalysts reported so far. The introduction of the Ni3 N/Ni4 N heterojunction could efficiently accelerate the migration of photocarriers and delay the recombination of electron–hole pairs.