Catalysis based on two-dimensional silicon has been under intense investigation recently. However, its substandard catalytic activity is far from industrialization. In this work, we demonstrate a new solution to this problem formulated on the batch synthesis of siloxene with an enhanced specific surface area (217.8 m(2) g(-1)). A two-dimensional porous structure was prepared, enabling great support and dispersion of metal nanoparticles. Catalytic evaluations of such hybrid structures for the (photo)thermal CO2 hydrogenation reaction and the electrochemical hydrogen evolution reaction revealed a significant performance advantage over the benchmark two-dimensional silicon structures synthesized via the conventional method. This work may confer notable viability on two-dimensional silicon for advanced energy, catalytic, and environmental applications.

Silica (SiO2) has been widely used as a support for various heterogeneous catalysts because of its Earth abundance, low cost, and large specific surface area. Except for the families of mesoporous and microporous silica, ordinary silica has long been perceived as just an inert support for better dispersion and mechanistic studies. However, recent advances have demonstrated new functionalities of structurally engineered silica to directly maneuver the catalytic performance, of which researchers are largely unaware. In this review, we start with a brief discussion about the fundamental merits of silica. Subsequently, we discuss distinctive features of silica through ingenious designs, which could enhance the activity, stability, and selectivity of heterogeneous catalysts. Finally, we put forward prospects and challenges for designing innovative silica-based catalysts, providing insights into viable techniques for high-performance heterogeneous catalysis.

Dry reforming of methane (DRM) is a promising route for greenhouse gas utilization, as it converts two primary greenhouse gases, CO2 and CH4, into industrially valuable synthesis gas. However, traditional thermal DRM suffers from coking and severe energy consumption, leading to a significant carbon footprint caused by the high-temperature process. In this context, photo-assisted DRM has become a promising emerging technology, as it utilizes renewable solar energy while ameliorating the massive fossil fuel expenditure of the traditional heating process. To solve these problems, catalysts designed on the nanoscale are essential for photo-assisted DRM to achieve high catalytic performance, effective solar energy conversion, and long-term stability. Herein, we highlight the recent advances in the design strategies of nanocatalysts applying various mechanisms, which span from photogeneration of carriers to localized surface plasmon resonance, and to several unconventional mechanisms for light harvesting and reaction facilitation. Finally, we propose future challenges and opportunities for the development of this emerging field.

In the past decades, silicon nanocrystals have received vast attention and have been widely studied owing to not only their advantages including nontoxicity, high availability, and abundance but also their unique luminescent properties distinct from bulk silicon. Among the various synthetic methods of silicon nanocrystals, thermal disproportionation of silicon suboxides (often with H as another major composing element) bears the superiorities of unsophisticated equipment requirements, feasible processing conditions, and precise control of nanocrystals size and structure, which guarantee a bright industrial application prospect. In this paper, we summarize the recent progress of thermal disproportionation chemistry for the synthesis of silicon nanocrystals, with the focus on the effects of temperature, Si/O ratio, and the surface groups on the resulting silicon nanocrystals' structure and their corresponding photoluminescent properties. Moreover, the paradigmatic application scenarios of the photoluminescent silicon nanocrystals synthesized via this method are showcased or envisioned.