An order/disorder/water junction system for highly efficient co-catalyst-free photocatalytic hydrogen generation
An order/disorder/water junction system for highly efficient co-catalyst-free photocatalytic hydrogen generation
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DOI：
10.1039/c5ee03100a
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发表时间：
2016-02
影响因子：
32.5
通讯作者：
Kan Zhang;Luyang Wang;Jung Kyu Kim;M. Ma;G. Veerappan;Chang-Lyoul Lee;K. Kong;Hyoyoung Lee;
中科院分区：
文献类型：
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作者：
Kan Zhang;Luyang Wang;Jung Kyu Kim;M. Ma;G. Veerappan;Chang-Lyoul Lee;K. Kong;Hyoyoung Lee;
TiO 2的表面工程面临着高太阳能-氢气转化效率的挑战。最近，表面无序的TiO 2，被称为黑色TiO 2，它可以吸收可见光和近红外太阳光，在许多重要的应用中引发了人们的兴趣。不幸的是，无定形表面层的光催化效果改善的机制仍然不清楚，似乎与传统的智慧相矛盾。在这里，我们展示了选择性的“无序工程”德固赛P-25二氧化钛纳米粒子，使用简单的室温溶液处理，保持独特的三相界面组成的有序的白色金红石和无序的黑色金红石与开放的结构，便于电解质的访问。超强碱中的强还原剂，由乙二胺中的锂（Li-EDA）组成，只能扰乱P-25的白色金红石相，留下蓝色的TiO 2纳米颗粒。由蓝色P-25产生的有序/无序/水结不仅可以通过II型带隙对准有效地在内部分离电子/空穴，而且还可以在含有牺牲剂的电解质中诱导强的析氢（H2）表面反应。结果，蓝色P-25显示出使用0.5wt%Pt（助催化剂）时13.89mmol h-1g-1和不使用任何助催化剂时3.46mmol h-1g-1的突出的H2生产速率。
Surface engineering of TiO2 is faced with the challenge of high solar-to-hydrogen conversion efficiency. Recently, surface-disordered TiO2, referred to as black TiO2, which can absorb both visible and near-infrared solar light, has triggered an explosion of interest in many important applications. Unfortunately, the mechanism underlying the improved photocatalytic effect from an amorphous surface layer remains unclear and seems to contradict conventional wisdom. Here, we demonstrate selectively “disorder engineered” Degussa P-25 TiO2 nanoparticles using simple room-temperature solution processing, which maintain the unique three-phase interfaces composed of ordered white-anatase and disordered black-rutile with open structures for easy electrolyte access. The strong reducing agent in a superbase, which consists of lithium in ethylenediamine (Li-EDA), can disorder only the white-rutile phase of P-25, leaving behind blue coloured TiO2 nanoparticles. The order/disorder/water junction created by the blue P-25 can not only efficiently internally separate electrons/holes through type-II bandgap alignment but can also induce a strong hydrogen (H2) evolution surface reaction in the sacrificial agent containing electrolyte. As a result, the blue P-25 exhibited outstanding H2 production rates of 13.89 mmol h−1 g−1 using 0.5 wt% Pt (co-catalyst) and 3.46 mmol h−1 g−1 without using any co-catalyst.