Heng-Liang Wu

The facile integration and stability of Si-based photoelectrode architectures are the remaining challenges in the photoelectrochemical (PEC) conversion of CO2 to fuels. In this work, the single-atomic-layer graphene is used as a functional bridging layer to integrate both Si photocathodes and photoanodes, which enable the direct electrodeposition of metal-based electrocatalysts (Cu, Ag, and In–Sn alloys) and a semiconductor-based catalyst Ni–Fe layered double hydroxide (Ni–Fe LDH) on graphene/Si heterojunction electrodes for PEC CO2 reduction and O2 evolution reactions, respectively. We demonstrate a PEC device with a full-cell configuration consisting of an In–Sn/graphene/Si heterojunction photocathode and a Ni–Fe LDH/graphene/Si heterojunction photoanode, exhibiting a reduced photovoltage of ∼1080 mV compared to the electrochemical counterparts. A self-powered PEC CO2 reduction with a solar-to-fuel conversion efficiency of 3.2% can be obtained by integrating the graphene/Si heterojunction photocathode and photoanode with a Si photovoltaic. In addition, in situ PEC X-ray absorption spectroscopy analyses show that the electrodeposited catalysts on the graphene layer lead to the transport of photogenerated electrons and preserve durability throughout the reaction. Utilizing graphene as a chemically inert atomic bridging layer enables the seamless integration of Si photoelectrodes with various catalysts, providing a platform for the PEC CO2 reduction reaction.

Aqueous zinc batteries are limited by dendrite growth and parasitic interfacial reactions that accelerate polarization and trigger early failure of Zn metal anodes. Here, a chemically active artificial interphase is engineered by coating Zn foil with a sulfonated Zr-based metal–organic framework (UiO-66-SO₃H) using PVDF as a binder, converting a conventional surface coating into an ion-coordination-active interface in a 2 M ZnSO₄ electrolyte. In situ Raman spectroscopy indicates that the sulfonate-oxygen coordination sites transiently interact with Zn²⁺ and promote partial desolvation, while density functional theory (DFT) calculations show more favorable Zn²⁺ adsorption at sulfonate sites than on pristine UiO-66. These coupled effects reduce the nucleation overpotential to 31.1 mV and decrease charge-transfer resistance, enabling more uniform Zn plating/stripping as verified by operando optical microscopy and X-ray tomography. As a result, symmetric Zn||Zn cells cycle stably for >1000 h at 0.5 mA cm^–2 (0.5 mAh cm^–2) and >800 h at 3 mA cm^–2 (3 mAh cm^–2), and Zn||Cu cells deliver an average Coulombic efficiency of ∼99.6% over >500 cycles. Full cells paired with a NaVO cathode retain >1000 cycles at 6C with improved stability. This work establishes sulfonate-directed Zn²⁺ coordination and interfacial desolvation within robust UiO-66 scaffolds as a practical strategy to extend the lifetime of aqueous Zn metal anodes.

Magnetic-field-enhanced defect-engineered Sn ₂ P ₂ S ₆ enables efficient spin-polarized CO ₂ -to-CH ₄ photocatalysis.

Valence electron count and electronegativity are used as descriptors to rationally anchor single atoms on WO ₃ . This optimizes surface charge localization and β-CO ₂ formation, significantly boosting photocatalytic CO ₂ reduction efficiency.

Photocatalytic conversion of CO ₂ into value‐added fuels offers a viable approach to combat climate change and address global energy demands. Here, we present a fluorine‐doped SnS ₂ thin film with sulfur vacancy (i.e., S _V ‐SnS ₂ :F), prepared via thermal evaporation, post‐sulfurization, and fluorine ion‐implantation. Substitution of sulfur with fluorine and sulfur vacancy formation changes the product selectivity from CH ₄ to CO with about 40‐fold enhanced yield and boosted internal quantum efficiency ( IQE ) of 0.52%. Transient absorption, in situ near‐ambient pressure X‐ray photoelectron, and in situ Fourier transform infrared spectroscopies, along with first‐principles density functional theory calculations, suggest that nearest‐neighbor Sn to F serves as an active site and stabilizes the *COOH intermediate. Our findings shed light on how F doping activates the nearby elements and its crucial role in intermediate stabilization toward selectivity change in a heterogeneous photocatalysis process.

The use of borate-functionalized In ₂ S ₃ is demonstrated as a promising approach for boosting the CO ₂ conversion efficiency through engineering the band energy edges.

A strategy is presented to mitigate copper surface reconstruction during electrochemical CO ₂ reduction reaction (EC‐CO ₂ RR) by conformally coating copper microcubes (CuMCs) with an ultrathin (≈2 nm) polydopamine (PDA) layer. The formation of nanocubes (30–50 nm in size) at the surface of microcubes at the early stages of the EC‐CO ₂ RR contributes to suppressed surface reconstruction and sustained Faradaic efficiency (FE) for C ₂ products. Furthermore, PDA coating effectively stabilizes adsorbed CO _atop and CO _bridge intermediates and promotes CC coupling. As a result, the FE for C ₂ products increases from 52.0 ± 4.0% for unmodified CuMCs to 81.6 ± 2.8% for PDA‐coated CuMCs at −1.18 V versus reversible hydrogen electrode (V _RHE ). The PDA coating effectively slows down the surface evolution process of the catalyst during electrolysis. After 18 h of continuous operation at −0.88 V _RHE , the CuMCs retain their original framework owing to a tightly adhered PDA layer that effectively stabilizes the surface and enhances catalyst durability. In situ surface‐enhanced infrared absorption spectroscopy confirms the presence of adsorbed CO _atop , CO _bridge , and OCCOH intermediates on PDA/CuMCs surface, which are believed to boost CC coupling. This work highlights the potential of polymer film to stabilize the catalyst surface and steer product distribution in CO ₂ electroreduction.

Lithium iron sulfide (Li₂FeS₂) exhibits unique characteristics, including multielectron redox behavior and abundant valence states, making it a promising candidate for electrode material in lithium-ion batteries. However, the sluggish charge transfer kinetics, low stability, and slow rate performance hamper its practical application. Herein, we propose a strategy to boost the electrochemical performance of Li₂FeS₂ by substituting F dopants with S sites through a two-step solid-state process. The effects of F dopants on material characteristics and electrochemical behaviors are investigated. Experimental results show that F dopants significantly enhance diffusion kinetics and rate performance, indicating improved interfacial activity in Li₂FeS_2−xF_x. Theoretical calculations confirm that F substitution occurs at the S site, enhancing charge mobility. After 100 cycles, the optimized Li₂FeS_2-xF_x cathode exhibits a specific capacity of 250 mAh g⁻¹, higher than pristine Li₂FeS₂. The improved electrochemical properties, diffusion kinetics, capacity, and rate performance are attributed to the enhanced structural stability from a stronger metal–fluorine bond compared to metal–sulfur, and increased Li⁺ ion diffusion due to a greater electronegativity difference.