Cross-dimensional Activation of Two-Dimensional Semiconductors for Photocatalytic Heterojunctions

Project Information

CATCH

Grant agreement ID: 101002219

DOI

10.3030/101002219

EC signature date 18 December 2020

Start date 1 May 2021

End date 31 October 2026

Funded under

• EXCELLENT SCIENCE - European Research Council (ERC)

Total cost

€ 1 999 946,00

EU contribution

€ 1 999 946,00

Coordinated by

OULUN YLIOPISTO
Finland

Periodic Reporting for period 3 - CATCH (Cross-dimensional Activation of Two-Dimensional Semiconductors for Photocatalytic Heterojunctions)

Reporting period: 2024-05-01 to 2025-10-31

Summary of the context and overall objectives of the project

Dimensionality is a fundamental feature for existence and evolution of materials. This applies to the 2D materials and their hierarchical structures where materials’ uniqueness in electronic, optical, and catalytic aspects arising also from the dimensional confinements. One of key paths to reach sustainability through materials innovation is to employ the 2D materials and their variants for photocatalysis, including pollutant removals and solar fuel production in forms of hydrogen. Despite numerous studies of the dimensionally unique materials, a general route to enable them as high-performance photocatalysts remains elusive.

The ERC-funded project CATCH focuses on a cross-dimensional activation strategy to implement practical photocatalysis. It benefits dimensional features of the 2D matrices, from which the activations involve the participants of nanomaterials of 0D, 1D, and 2D to form photocatalytic heterostructures. Synergic impacts crossing 2D-nD are expected to lead to > 95%/hour rates for removals of selected pollutants and >20% apparent quantum efficiencies for H2 evolution under visible light. It is supported by three subobjectives (SOs) of compatible host and guest materials designs, realizations and functionalization of heterojunctions, and mechanistic studies to understand photocatalysis crossing the dimensionalities.

CATCH establishes a possible blueprint for 2D photocatalysts crossing materials dimensionalities. It considers physical and electronic merits from the planar hosts and their variants when combining with low-dimensional guests. Materials activation strategy for the 2D materials also benefits activations of materials of other dimensions for applications beyond photocatalysis, e.g. in electronics, optics etc. The high-performance photocatalysts developed in CATCH are envisaged as base materials in photocatalytic reactors where the end-product of hydrogen will be collected and used in various fields. CATCH practices methodological transfers obtained from photocatalysis to other relevant fields, e.g. surface wetting, electrocatalysis, and optoelectronics.

CATCH offers the solutions to practical photocatalysis to benefit human’s sustainability. The high-performance and durable photocatalysts applied to harvest solar energy for pollutant removal and hydrogen production are foreseen to possibly alleviate two urgent crises of environmental pollution and clean energy shortage.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

CATCH undergoes four work packages (WPs) of computational predictions, synthesis and refinement, in house and advanced characterizations, and mechanistic studies.

In general, the project has been well implemented according to the plan. In the period, 25 peer-reviewed journal articles, including 2 reviews, were published. In hetero-site selections (related to WP1, SO1) and materials realizations (related to WP2, SO2), after thoroughly surveying the 2D databases, computationally we have predicted various new 2D semiconductor matrices, such as 2D transition metal dichlorides, defective trihalide monolayers, and Ni tellurate. The tellurate was synthesized successfully in the lab. A machine learning algorithm was established to predict the heterojunctions with materials from 2D materials databases. Experimentally (related to WP2, SO2), shape-controlled synthesis has been performed and many synthetic materials have been realized. In activations, 0D decorates were loaded on to Ce metal–organic framework, nickel composites composed of flakes and 2D hydroxides. We realized high performances of photocatalysts, despite some of their morphologies are mixed. An apparent quantum efficiency of 20.45% at visible light region (420 nm) was reached for hydrogen evolution, and a removal rate of 95.6% for Cr (VI) under sunlight in 30 minutes. The 0D+2D Co3O4/Co(OH)2 was capable in photocatalytic hydrogen production and degradation of persistent microplastics under visible light. In mechanistic study (WPs 3,4 and SO3), the in-situ x-ray studies were performed along with density functional theory investigations of reaction intermediates during the photocatalysis.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The project is aimed to reach and study high-performance photocatalysts based on 2D semiconductor matrices. In searching for the suitable 2D matrices, the stable 2D semiconductive and photocatalytic Ni3TeO6 was synthesized following theoretical prediction. Beside introducing a new 2D material, the route combining theoretical and experimental endeavors is hoped to inspire similar works in novel materials enrichment. At the 0D nanomaterials decorations, we found a high apparent quantum efficiency of 20.45% at 420 nm. The photochromatic effects were identified as a prompting factor to boost efficiency of the cross-dimensionally active photocatalyst. The cross-dimensionally activated 2D materials can photocatalytically remove persistent microplastics under visible light, along with hydrogen evolution. This functionality is unexpected but realized. It offers a starting point for the photoreforming of pollutive microplastics. Moreover, the materials synthetic paths to reach the Ni decorated 2D flakes have been proved useful in preparations of durable photocatalysts for photocatalytic hydrogen reactors.

Research endeavours in cross-dimensional activations are expected to reach 2D+0D, 2D+1D and 2D+2D photocatalysts. Variants of the 2D matrices may get along with the individual slabs for materials activations. Mechanistic studies of photocatalysis down to nanosecond scales are also in a reasonable reach. Along with continuous enhancements of the quantum efficiency of photocatalytic hydrogen evolutions on activated 2D-materials-based heterostructures, photocatalysts resulted from CATCH are expected to be mounted on scalable photocatalytic reactors for practical hydrogen evolution under solar/visible light.

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