Role of surface engineering of hybrid structure for high performance quantum dots based photoelectrochemical hydrogen generation
| Autor: | Federico Rosei, Ghada Bassioni, Pawan Kumar, Zhiming Wang, Karthik Suresh, Omar Abdelkarim, Aycan Yurtsever, Kulbir Kaur Ghuman, Fabiola Navarro-Pardo, Gurpreet Singh Selopal |
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| Rok vydání: | 2022 |
| Předmět: |
Photocurrent
Materials science business.industry General Chemical Engineering Nanoparticle 02 engineering and technology General Chemistry Surface engineering 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Industrial and Manufacturing Engineering 0104 chemical sciences Quantum dot Environmental Chemistry Optoelectronics Water splitting Nanorod Density functional theory 0210 nano-technology business Hydrogen production |
| Zdroj: | Chemical Engineering Journal. 429:132425 |
| ISSN: | 1385-8947 |
| Popis: | We report the synthesis of a TiO2 hybrid structure, consisting of a combination of nanorods and nanoparticles, subsequently treated with hydrazine to enhance the performance of photoelectrochemical (PEC) hydrogen (H2) generation. The optimized TiO2 hybrid photoanode sensitized with Quantum dots (QDs), yields a saturated photocurrent density of 4.25 mA cm−2 (at 0.8 V vs RHE), which is 172% higher than that of the reference sample. The optimized hybrid photoanode treated with hydrazine exhibits an additional 28% increase in the saturated photocurrent density, reaching 5.43 mA cm−2 with CdS QDs, and 8.12 mA cm−2 with CdS/CdSe QDs (at 0.8 V vs RHE), while maintaining 80% of the initial value of photocurrent density, after 2 h of continuous one sun illumination (AM 1.5 G, 100 mW cm−2). We used Density Functional Theory with Hubbard energy correction (DFT + U) calculations to describe the mechanism that underpins this significant improvement. DFT + U results highlighted that the concentration of the hydrazine treatment plays a crucial role and affects the sites (surface or interstitial) where nitrogen may be present. This eventually affects the recombination centers within the hybrid photoanode. Thus, the results of this work define a promising strategy to optimize the morphology of the hybrid photoanodes via hydrazine surface engineering to fabricate efficient and stable PEC water splitting devices for H2 generation. |
| Databáze: | OpenAIRE |
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