Lydia Helena Wong

Direct photocatalytic upcycling of nonbiodegradable plastics using single‑atom catalysts (SACs) remain limited by the symmetric coordination of isolated metal sites, which constrains intermediate binding and charge transfer. Here, we reconstruct the heptazine units of polymeric carbon nitride (PCN) via a salt‐induced strategy, transforming S─CoPCN with a predominantly symmetric Co─N ₄ coordination environment into A─CoPCN featuring predominantly asymmetric Co─N ₃ configurations. Under white‐light irradiation at room temperature and 1 bar O ₂ , A─CoPCN enables the conversion of polystyrene to benzoic acid with a yield of 39.6% and a carbon recovery of 71.6%. Compared with previously reported systems that often require elevated temperatures, high O ₂ pressures, or external oxidants, this system operates under markedly milder conditions. The catalyst further demonstrates broad applicability across diverse nonbiodegradable plastics, including polystyrene, polyisobutylene, polylactic acid, polypropylene, polyethylene, and polyvinyl acetate. Mechanistic studies combining advanced spectroscopy and density functional theory calculations reveal that symmetry breaking suppresses electron delocalization, upshifts the Co d‐band center, and lowers exciton binding energy, thereby facilitating charge separation and transfer, promoting O ₂ adsorption and activation to generate reactive •O ₂ ⁻ species for efficient plastic upcycling. This work identifies coordination asymmetry as a key design principle for SACs and provides a general strategy for enhancing photocatalytic plastic upcycling.

Wide‐bandgap kesterite (Cu ₂ ZnSnS ₄ , CZTS) is an earth‐abundant and environmentally friendly absorber, making it a promising candidate for both outdoor and indoor photovoltaic applications. However, device performance remains limited by multiple loss mechanisms, including recombination at the CdS/CZTS heterojunction and resistive back‐contact losses at the Mo/CZTS interface. Here, we report solution‐processed CZTS devices in which controlling the cooling dynamics after device annealing in ambient air provides an effective and scalable strategy to overcome these limitations and enable stable, high‐performance devices. By implementing a rapid cooling process (RCP), we suppress non‐radiative recombination at the CdS/CZTS heterojunction, resulting in a decrease in saturation current density ( J ₀ ) by three orders of magnitude. Moreover, RCP improves the Mo/CZTS back contact by modifying the MoS ₂ ‐related region, which may facilitate hole extraction and reduce back‐contact losses. As a result of these combined interface improvements, RCP‐treated devices retain a PCE of 11.1% after ∼1500 h of damp heat aging at 85°C, with a Voc corresponding to 62.4% of the thermodynamic limit. The RCP device also delivers an indoor PCE of 15.9% under 2700 K LED illumination, representing the highest reported performance for kesterite solar cells under indoor conditions at 1000 lux.

Soft robotics is evolving from a field centered on compliant mechanisms toward a broader paradigm of embodied physical intelligence, in which materials, mechanics, sensing, and computation are deeply integrated. Despite rapid progress, major challenges remain in actuation, perception, autonomy, scalability, and real-world deployment. In this Nano Focus article, we highlight emerging frontiers and technological challenges spanning multifunctional materials, distributed sensing, additive manufacturing, artificial intelligence, and biohybrid systems. Advances in nanoscience and nanotechnology increasingly underpin these developments by enabling the integration of sensing, actuation, and adaptive functionalities across length scales. Collectively, these advances are establishing a foundation for intelligent matter, programmable physical intelligence, and life-like adaptive systems.

Achieving ultralow optical loss, broadband transparency, and mechanical softness within a single polymer network remains a long‐standing challenge for soft photonics. Here, we report a molecularly engineered class of UV‐curable thiol‐ene‐aromatic polymers that reconciles optical performance with mechanical compliance. By combining thiol crosslinkers with aromatic acrylates to form a low‐absorption network and introducing a phenyl‐bearing comonomer to mitigate near‐infrared vibrational overtone absorption while tuning elasticity and printability, the optimized A50 formulation exhibits ultralow optical attenuation of ∼0.004 dB cm ^{− 1} , together with broadband transparency from 310 to 1100 nm and transmittance exceeding 90% above 380 nm at millimeter‐scale thicknesses. The same formulation remains mechanically compliant and supports high‐fidelity freeform UV‐based 3D printing, while exhibiting high thermal stability (onset ≈333°C). Leveraging this combination of optical and mechanical properties, we demonstrate deformable waveguides and bioinspired optomechanical devices capable of robust, multichannel optical sensing under repeated low‐force interactions and compliant manipulation. This work establishes a molecular design strategy for creating soft polymers with ultralow optical loss, providing a materials platform for next‐generation soft photonic interfaces and adaptive robotic systems.

The synthesis of high-purity lepidocrocite-type titanate nanotubes from natural ilmenite minerals remains challenging due to the presence of iron impurities and the limited understanding of their structural stability during thermal treatment. This study presents a controlled purification and hydrothermal synthesis route for producing high-purity lepidocrocite-type titanate nanotubes from ilmenite-derived titanium dioxide (TiO₂) nanoparticles. Titanium oxosulfate (TiOSO₄) leachate obtained from the sulfate process was prepared via ethylenediaminetetraacetic acid (EDTA)-assisted purification, yielding TiO₂ nanoparticles with a purity of 99%, which were subsequently converted into titanate nanotubes by hydrothermal treatment. Structural characterization confirmed that the nanotubes retained their multilayered lepidocrocite-type titanate (H₂Ti₃O₇) structure after calcination up to 300°C while exhibiting improved crystallinity and a well-defined tubular morphology. The optimized sample (PF300) exhibited the highest specific surface area (256.9 m²g⁻¹) and pore volume (0.54 cm³g⁻¹), together with a direct band gap of 3.29 eV. Photocatalytic performance was evaluated through the degradation of methylene blue (MB), achieving removal efficiencies of 98% and 96% under ultraviolet and visible light irradiation, respectively. The outstanding performance originated from the synergistic effect of adsorption and photocatalysis, with preserved tubular morphology, a layered lepidocrocite structure, a high specific surface area, favorable optical properties, and efficient charge separation. These findings demonstrate that EDTA-assisted purification combined with controlled thermal treatment provides an effective strategy for producing high-performance lepidocrocite-type titanate nanotubes from natural ilmenite, with promising potential for solar energy-harvesting applications.

This paper presents the third version of the Efficiency Tables compiling the record efficiencies of materials considered as emerging inorganic absorbers for photovoltaic technologies. The materials collected in these Tables are selected based on their progress in recent years, and their demonstrated potential as future photovoltaic absorbers. The first part of the paper consists of an overview of the current status of emerging photovoltaic materials. The second section details the inclusion criteria used for the different technologies presented in the paper, the verification means used by the authors, and recommendations for measurement best practices. The third part compiles the highest world-class certified solar cell efficiencies, and the highest non-certified cases (some independently confirmed). This section includes a brief state-of-the-art for the different classes of materials defined in the paper. The final part summarizes the main conclusions of this third version of Emerging Inorganic Solar Cell Efficiency Tables, highlighting the most relevant progresses published in the last two years.

Guest editors for this themed issue, from left to right: Prof. Robert Hoye, Prof. Frank Osterloh, Prof. Yun Jeong Hwang, Prof. Yanwei Lum, Prof. Lydia Wong.

Bias-free photoelectrochemical devices provide a sustainable route for solar hydrogen production from alkaline seawater, however, the requirement for large potential for anodic oxygen evolution and undesired chloride oxidation in seawater limit their efficiency. By leveraging the low oxidation potential of hydrazine, a toxic pollutant, bias-free devices can achieve high-performance hydrogen production and simultaneous degradation of hydrazine, effectively avoiding chloride oxidation. Here, we design a self-powered artificial leaf device, comprising a perovskite photocathode integrated with a noble-metal-free oxide catalyst for direct solar hydrogen production and hydrazine oxidation. The device exhibits a high photocurrent density of 25 mA cm^-2 and stability for 3 days under 1-sun illumination. Upscaling the artificial leaf device enables near-complete hydrazine degradation to below 1 ppb within ≈ 30 h under zero-bias operation. This study provides a scalable and sustainable approach for simultaneous hydrogen generation and pollutant removal, advancing the use of solar energy in environmental applications.

The performance of quasi‐one‐dimensional (Q1D) Sb ₂ (S,Se) ₃ photovoltaics is often hindered by its unfavorable crystallographic orientation that limits charge transport. Despite advances in substrate engineering, orientation control has largely been pursued through isolated parameters, and a holistic strategy that integrates multiple factors remains absent. Herein, we break this bottleneck by demonstrating that thermal‐kinetic modulation during post‐annealing, together with substrate engineering, offers a decisive route for achieving preferred crystallographic orientation. By employing a rapid heating process, we actively regulate the crystallization kinetics on moderately inducing substrates, which promotes the vertical growth of (Sb ₄ X ₆ ) _n ribbons and thus secures a highly oriented (hk1) texture. This approach yields a champion device with a power conversion efficiency (PCE) of 9.35%, primarily attributed to improved charge collection efficiency enabled by the vertically oriented Sb ₂ (S,Se) ₃ , along with a partial contribution from suppressed deep‐level defect recombination. This work represents a significant step from passive substrate reliance to active thermal‐kinetic control, offering a novel and general strategy for mastering crystallization in Q1D and analogous photovoltaic materials.