Highly efficient BiVO4 single-crystal photocatalyst with selective Ag2O-Ag modification: orientation transport, rapid interfacial transfer and catalytic reaction
Highly efficient BiVO4 single-crystal photocatalyst with selective Ag2O-Ag modification: orientation transport, rapid interfacial transfer and catalytic reaction
复制标题
选择性Ag2O-Ag修饰的高效BiVO4单晶光催化剂：定向传输、快速界面转移和催化反应
DOI：
10.1039/c8dt00780b
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发表时间：
2018-05-14
影响因子：
4
通讯作者：
Yu, Jiaguo
中科院分区：
文献类型：
--
作者：
Wang, Xuefei;Liao, Dan;Yu, Jiaguo
将晶面工程与选择性界面修饰相结合是提高半导体光催化剂光催化性能的有效途径。例如，当Pt助催化剂选择性地修饰在具有暴露的（010）和（110）晶面的BiVO 4单晶光催化剂的（010）晶面上时，BiVO 4表现出优异的光催化活性。鉴于金属Pt的高成本和稀有性，期望发现显示出与Pt相当的活性的低成本电子助催化剂。在本研究中，Ag 2 O-Ag作为一种新型高效的电子助催化剂，通过简单的光沉积金属Ag并随后通过低温煅烧（100-400 ℃）将其部分氧化为Ag 2 O，选择性地修饰在单晶BiVO 4光催化剂的（010）面上。Ag选择性地修饰在BiVO 4单晶的富电子面（010）上，而Ag 2 O选择性地在Ag表面生成，从而形成Ag 2 O-Ag/BiVO 4光催化剂。结果，Ag 2 O-Ag/BiVO表现出与Pt/BiVO 4几乎相当的活性，但明显高于单独的Ag/BiVO 4或BiVO 4的活性。这是由于BiVO 4的晶面工程和Ag 2 O-Ag电子助催化剂的选择性改性协同作用的结果。详细地说，BiVO 4的单晶结构导致光生载流子的取向传输，而金属Ag有效地转移BiVO 4的光生电子，然后，Ag 2 O作为活性位点加速溶解氧的还原。考虑到我们目前的合成策略是容易的，可控的和经济的，本研究提供了深入了解高效半导体光催化剂的设计和合成。
Coupling crystal-facet engineering with selective interfacialmodification has been demonstrated to be an effective strategy to enhance the photocatalytic performance of semiconductor photocatalysts. For instance, BiVO4 exhibited excellent photocatalytic activity when Pt cocatalyst was selectively modified on the (010) facet of BiVO4 single-crystal photocatalyst with exposed (010) and (110) facets. In view of the high cost and rarity of metallic Pt, it was desirable to discover low-cost electron cocatalysts that show comparable activity with Pt. In the study, Ag2O-Ag as a novel and highly efficient electron cocatalyst was selectively modified on the (010) facet of single-crystal BiVO4 photocatalyst via facile photodeposition of metallic Ag and its subsequent partial oxidation to Ag2O via low-temperature calcination (100-400 C). In detail, Ag was selectively modified on the electron-rich (010) facet of BiVO4 single crystal, while Ag2O was selectively formed on the Ag surface, resulting in the formation of Ag2O-Ag/BiVO4 photocatalyst. As a result, Ag2O-Ag/BiVO, exhibited nearly comparable activity with Pt/BiVO4, but clearly higher activity than Ag/BiVO4 or BiVO4 alone. The enhanced performance was ascribed to the synergistic effect of crystal facet engineering of BiVO4 and selective modification of Ag2O-Ag electron cocatalyst. In detail, the single crystal structure of BiVO4 results in the orientation transport of photogenerated carriers, while metallic Ag effectively transfers photogenerated electrons of BiVO4 and then, Ag2O as the active site accelerates the reduction of dissolved oxygen. Considering that our present synthetic strategy is facile, controllable and economical, this study provides insight into the design and synthesis of highly efficient semiconductor photocatalysts.