Highly Efficient CdS/WO3 Photocatalysts: Z-Scheme Photocatalytic Mechanism for Their Enhanced Photocatalytic H2 Evolution under Visible Light
Highly Efficient CdS/WO3 Photocatalysts: Z-Scheme Photocatalytic Mechanism for Their Enhanced Photocatalytic H2 Evolution under Visible Light
复制标题
高效 CdS/WO3 光催化剂：Z 型光催化机制增强可见光下光催化析氢
DOI：
10.1021/cs500794j
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发表时间：
2014-10-01
期刊：
影响因子：
12.9
通讯作者：
Xie, Teng F.
中科院分区：
文献类型：
--
作者：
Zhang, Li J.;Li, Shuo;Xie, Teng F.
自然光合作用通常被认为是实现太阳能转换的有效机制。我们构建了CdS/WO 3纳米结，通过模仿自然光合作用实现了清洁氢燃料进化的Z-方案。虽然WO 3不能单独用于水裂解放氢，但它可以通过以乳酸盐为电子供体的Z-方案机制显着增加CdS的H-2放出和活性。CdS/WO_3光催化剂在CdS浓度为20wt%时具有369 μ mol·g ~（-1）·h ~（-1）的高放氢速率，是以乳酸为电子供体的CdS的5倍。为了进一步提高产氢速率，我们引入贵金属Pt来改善CdS和WO 3之间的电荷传输。用WPC 3获得了高达2900 μ mol g（-1）h（-1）的良好的H-2释放速率，约为用可见光辐射的WC 20的速率的7.9倍。有趣的是，CdS/WO 3的光催化机理与以前报道的机理不同。TPV和SPV结果表明，CdS/WO 3的Z型体系基于Z型机制，能有效促进CdS中光生电荷的电荷分离和抑制电荷重组，从而在可见光下产生高效的H-2.
Natural photosynthesis is usually recognized as an efficient mechanism to achieve solar energy conversion. We construct a CdS/WO3 nanojunction achieving a Z-scheme for clean hydrogen fuel evolution by 6 mimicking the natural photosynthesis. Although WO3 alone cannot be used for H2 evolution from water splitting, it can significantly increase the H-2 evolution & activity of CdS through a Z-scheme mechanism with lactate as electron donor. I The CdS/WO3 photocatalyst has a high H-2 evolution rate of 369 mu mol g(-1) h(-1) at a CdS concentration of 20 wt %, which is 5 times as high as that of CdS with it lactic acid as electron donor. For further improving the hydrogen production rate, we introduce the noble metal Pt to ameliorate the charge transport between CdS and WO3. Good H-2 evolution rates up to 2900 mu mol g(-1) h(-1) were obtained with WPC3, which is about 7.9 times the rate of WC20 with visible radiation. The interesting thing is that the photocatalytic mechanism of CdS/WO3 is different from the previously reported mechanism. The results of TPV (transient photovoltage) and SPV (surface photovoltage) indicate that the Z-scheme system of CdS/WO3 can effectively promote charge separation and depress the charges recombining of photogenerated charge in CdS, based on the Z-scheme mechanism, resulting in efficient H-2 production activity under visible light.