Proton exchange membrane fuel cells (PEMFCs) have attracted significant attention as sustainable energy technologies due to their efficient energy conversion and fuel flexibility. However, several challenges remain, such as low catalytic activity of fuel cell membrane electrode assembly (MEA), insufficient mass transfer performance, and performance degradation caused by catalyst deactivation over long period of operation. These issues are especially significant at high current densities, limiting both efficiency and operational lifespan. Mesoporous carbon materials, characterized by a high specific surface area, tunable pore structure, and excellent electrical conductivity, are emerging as crucial components for enhancing power density, mass transfer efficiency, and durability of PEMFCs. This review first discusses the properties and advantages of mesoporous carbon and outlines various synthetic strategies, including hard template, soft template, and template-free approaches. It then comprehensively examines the applications of mesoporous carbon in PEMFCs, focusing on their effects on the catalyst and gas diffusion layer. Finally, it concludes with future perspectives, emphasizing the need for further research to fully exploit the potential of mesoporous carbon in PEMFCs.

Perovskite-based photovoltaic devices have garnered significant interest owing to their remarkable performance in converting light into electricity. Recently, the focus in the field of perovskite solar cells (PSCs) has shifted towards enhancing their durability over extended periods. One promising strategy is the incorporation of two-dimensional (2D) perovskites, known for their ability to enhance stability due to the large organic cations that act as a barrier against moisture. However, the broad optical bandgap and limited charge transport properties of 2D perovskites hinder their efficiency, making them less suitable as the sole light-absorbing material when compared to their three-dimensional (3D) counterparts. An innovative approach involves using 2D perovskite structures to modify the surface properties of 3D perovskite. This hybrid approach, known as 2D/3D perovskites, while enhancing their performance. Beyond solar energy applications, 2D perovskites offer a flexible platform for chemical engineering, allowing for significant adjustments to crystal and thin-film configurations, bandgaps, and charge transport properties through the different organic ligands and halide mixtures. Despite these advantages, challenges remain in integration of 2D perovskites into solar cells without compromising device stability. This review encapsulates the latest developments in 2D perovskite research, focusing on their structural, optoelectronic, and stability attributes, while delving into the challenges and future potential of these materials.

Hydrogen is a promising energy carrier that is expected to play a crucial role in helping Canada achieve its net-zero target by 2050. However, reducing the ambiguity in regulatory frameworks is essential to incentivize and facilitate international trade in hydrogen. To this end, regulators must agree on quantification methodologies that consider life cycle boundaries, process descriptions, co-product allocation, conversion constants, and certification units. Several studies have highlighted the importance of life cycle assessment (LCA) as a standardized, relevant method for estimating the carbon footprint associated with hydrogen production and evaluating its environmental sustainability. As such, LCA-based certification schemes could help create a transparent hydrogen market. The aim of this study is to validate the proposed harmonized LCA-based methodology for quantifying hydrogen production’s carbon intensity. This methodology follows a consistent scope and life cycle inventory (LCI) development criteria, alongside a rigorous data quality assessment. The well-to-gate carbon intensities of six hydrogen production pathways are compared, which range from 0.26 to 10.07 kg CO_2e per kg of hydrogen (kg CO_2e/kg H₂), against the hydrogen carbon intensity thresholds established by the Canadian Clean Hydrogen Investment Tax Credit (CHITC). For example, the biomass gasification with carbon capture (CC) pathway demonstrates the lowest carbon intensity, while thermochemical pathways, such as steam methane reforming of natural gas without CC, poses challenges to meeting the maximum CHTIC threshold of 4 kg CO_2e/kg H₂.

The pursuit of high energy density and sustainable energy storage devices has been the target of many researchers. However, safety issues such as the susceptibility of conventional liquid electrolytes to leakage and flammability, as well as performance degradation due to uncontrollable dendrite growth in liquid electrolytes, have been limiting the further development of energy storage devices. In this regard, gel polymer electrolytes (GPEs) based on lignocellulosic (cellulose, hemicellulose, lignin) have attracted great interest due to their high thermal stability, excellent electrolyte wettability, and natural abundance. Therefore, in this critical review, a comprehensive overview of the current challenges faced by GPEs is presented, followed by a detailed description of the opportunities and advantages of lignocellulosic materials for the fabrication of GPEs for energy storage devices. Notably, the key properties and corresponding construction strategies of GPEs for energy storage are analyzed and discussed from the perspective of lignocellulose for the first time. Moreover, the future challenges and prospects of lignocellulose-mediated GPEs in energy storage applications are also critically reviewed and discussed. We sincerely hope this review will stimulate further research on lignocellulose-mediated GPEs in energy storage and provide meaningful directions for the strategy of designing advanced GPEs.

As the push for higher-energy lithium-ion batteries accelerates, developing electrolytes that remain stable at high voltages has become critical.

Artificial carbon fixation is a promising pathway for achieving the carbon cycle and environment remediation. However, the sluggish kinetics of oxygen evolution reaction (OER) and poor selectivity of CO₂ reduction seriously limited the overall conversion efficiencies of solar energy to chemical fuels. Herein, we demonstrated a facile and feasible strategy to rationally regulate the coordination environment and electronic structure of surface-active sites on both photoanode and cathode. More specifically, the defect engineering has been employed to reduce the coordination number of ultrathin FeNi catalysts decorated on BiVO₄ photoanodes, resulting in one of the highest OER activities of 6.51 mA cm⁻² (1.23 V_RHE, AM 1.5G). Additionally, single-atom cobalt (II) phthalocyanine anchoring on the N-rich carbon substrates to increase Co–N coordination number remarkably promotes CO₂ adsorption and activation for high selective CO production. Their integration achieved a record activity of 109.4 μmol cm⁻² h⁻¹ for CO production with a faradaic efficiency of > 90%, and an outstanding solar conversion efficiency of 5.41% has been achieved by further integrating a photovoltaic utilizing the sunlight (> 500 nm).

Ultraprecise fluorescence nanoscopy techniques such as MINFLUX and RASTMIN are enabling molecular-scale imaging and tracking in biologically relevant conditions. However, their implementation is challenging and requires stabilizing the position of the sample during the relatively long measurement times of minutes or tens of minutes. Scientists have developed an open-source system based on commonly available hardware that achieves sub-nanometric stabilization of the sample position for hours, opening the way for widespread application of single-molecule localization with true nanometer precision.

Researchers led by Prof. Zihan Geng at Tsinghua University and collaborators have developed a hybrid noise analysis method for single-pixel imaging in complex environments. By integrating physically consistent degradation modeling with structured training, the method overcomes illumination fluctuations, blurring, jitter, and detection noise, enabling high-quality image reconstruction under complex degradations. This advance enhances the stability of single-pixel imaging in real-world settings, laying a foundation for applications in life sciences, industrial inspection, and remote sensing.

Recently, addressing the inherent timescale mismatch challenge between fast and slow responses in optoelectronic sensors, a collaborative team from Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO), Chinese Academy of Sciences (Yukun ZHAO, Shulong LU, Min JIANG), Fudan University (Lifeng BIAN), and Suzhou University of Science and Technology (Jianya ZHANG) has proposed an innovative monolithic integration scheme. By combining surface defect introduction and local contact interface design with a gallium nitride (GaN) nanowire lift-off technique that eliminates the interference from the underlying silicon substrate, the team integrates fast and slow responses into a single device. This results in a transparent bifunctional device capable of self-driven detection and neural synaptic integration, with omnidirectional (360°) detection capability. As a photodetector, the device demonstrates the millisecond-level response speeds, while it exhibits the second- to minute-level relaxation time as an artificial synapse, achieving an over 1000-fold contrast in response dynamics. The device has been validated in the intelligent perception systems for humanoid robots successfully, advancing the development of multifunctional monolithic optoelectronic devices and providing a solid foundation for further research in related fields.

 

The work entitled "A dual-mode transparent device for 360° quasi-omnidirectional self-driven photodetection and efficient ultralow-power neuromorphic computing" was published in Light: Science & Applications.