Recent trends have shown that artificial photosynthesis is moving from proof-of-concept demonstrations to integrated solar-to-chemical systems. This places new demand on photovoltaic absorbers, catalysts, and reactors to operate as coupled energy conversion platforms. Metal halide perovskites play a distinctive role in this transition because of their high efficiency, bandgap tunability, and low-temperature processability, allowing the photovoltaic output to be tailored across single-junction, tandem, and multijunction architectures. This perspective examines recent advances in perovskite photovoltaics through the lens of system-level requirements for solar fuel production. Single-junction modules are considered scalable photovoltaic drivers for modular photovoltaic-electrochemical systems. In contrast, tandem and multijunction devices are discussed as voltage-engineered platforms for water splitting and CO2 reduction. We further compare representative artificial photosynthesis configurations, highlighting how interfacial stability, current-voltage matching, encapsulation, catalyst selectivity, and reactor design collectively determine solar-to-fuel conversion performance. By examining these advances from a system-level perspective, we aim to identify the key design principles and research priorities needed to translate perovskite photovoltaics into efficient, stable, and scalable solar-to-chemical platforms.

Mixed ionic-electronic conductivity of metal halide perovskites is a critical factor determining their application in optoelectronics, as well as the emerging field of optoionics. In particular, ionic migration in response to voltage bias and light contributes to the operational instability of halide perovskite materials and devices. A promising strategy to control ion migration is dimensional reduction, achieved by incorporating bulky organic cations between inorganic slabs to form two-dimensional or layered hybrid halide perovskites. In this perspective article, we discuss the mixed conductivity of layered halide perovskite materials and the impact on the operational stability of perovskite optoelectronics and emerging applications.

Redox mediators in water-in-salt electrolytes (WiSE) offer a compelling platform for durable, safe, and efficient Zn-ion battery. Here we investigate two model systems: MnCl2 and HAuCl4 dissolved in 15 m ZnCl2. Using a carbon positive electrode enables areal capacities of approx. 1 mAh/cm2, outperforming traditional electrodes with solid thin-film materials, e.g., phosphate olivines. This capacity is available in a WiSE volume, which fits the standard 2032 coin cell. The WiSE environment substantially alleviates the "dead MnO2" problem, while gamma-MnO2 is generated by anodic oxidation of Mn2+ over a broad potential region. The charge transfer is diffusion-limited, with ion transport primarily controlled by the viscosity of the WiSE. Remarkably, Au and Mn display strikingly similar electrochemical signatures, each producing broad, asymmetric voltammetric peaks with a formal potential near 1.7 V vs Zn2+/Zn, despite Mn redox couples being shifted by ca. 0.7 V below their standard potentials. The observed potential shifts arise from chloromanganate formation as well as from WiSE-specific effects. The potentials are conveniently referenced to the Ru(NH3)63+/2+ couple, which is essentially insensitive to ZnCl2 concentration. Gold undergoes rapid oxidative dissolution to AuCl4- . The Au-Zn alloys are identified by distinct features at anodic stripping, as well as by SEM, EDX and XPS. These findings highlight both the opportunities and mechanistic complexities of liquid-phase redox mediators for high-capacity Zn-ion energystorage systems with WiSE.

Perovskites solar cells (PSCs) have emerged, since 2009, as the most promising technology to replace/complement crystalline silicon PV. [1] Outstanding results of PCE up to 26.7 % have been obtained using perovskites (eg. MAPbI 3 ) in just a few years of research. The continuous improvement of the efficiency in PSCs has been achieved using commercially available spiro-OMeTAD as hole-transporting material (HTM). However, spiro-OMeTAD is an expensive material due to its difficult purification and multi-step synthetic protocols (in harsh conditions) which limits its future use in large-scale applications. As a consequence, great efforts in the synthesis and characterization of alternative organic low-cost molecules for its application as HTMs have been reported in the recent years, including PAH-based, spiro-containing or dopant-free materials. [2] Our research group reported two doped-HTMs based on electron-rich spiranic scaffolds, namely, spiro-POZ and spiro-PTZ which exhibit a similar performance of the reference material and improved long-term stability (more than 300 days of exposure to ambient conditions and more than 1200 h under continuous 1 sun illumination) in sharp contrast with the reference of spiro-OMeTAD. [3] Motivated by these excellent results, we have designed four new derivatives based on spiro-PTZ functionalized with asymmetric diphenylamine units that have been incorporated in PSCs improving the PCE of the devices up to 25.75%, surpassing clearly the power conversion efficiency and stability of spiro-OMeTAD. Furthermore, large area mini module (25 cm 2 ) also shows an outstanding PCE above 22%, pointing spiro-PTZ derivatives as one of the most efficient HTMs reported in bibliography. References [1] A. Kojima, K. Teshima, Y. Shirai, T. Miyasaka, J. Am. Chem. Soc. 2009 , 131 , 6050-6051. [2] J. Urieta-Mora, I. García-Benito, A. Molina-Ontoria, N. Martín, Chem. Soc. Rev. 2018 , 47 , 8541-8571. [3] J. Urieta-Mora, I. García-Benito, L.-A. Illicachi, J. Calbo, J. Aragó, A. Molina-Ontoria, E. Ortí, N. Martín, M. K. Nazeeruddin, Sol. RRL 2021 , 5 , 2100650. Figure 1

Despite well‐matching indoor illumination spectra, the performance of wide bandgap perovskite solar cells (WB‐PSCs) for indoor photovoltaics (i‐PV) is hindered by photo‐induced halide phase segregation and trap‐assisted non‐radiative recombination. Herein, a Triple Passivation Treatment (TPT) reassembly strategy is presented to simultaneously suppress bulk and surface defects. TPT induces a transition in perovskite surface energetics from n ‐type to p ‐type and remarkably increases the photoluminescence quantum yield from 0.5 to 2.1%, creating a more favorable band alignment for hole extraction whilst substantially reducing halide phase segregation. As a result, 1.75 eV WB‐PSCs achieve an indoor Power Conversion Efficiency (iPCE) of 37.6% under 1000 lux illumination. Under standard sunlight conditions, the devices reach a Power Conversion Efficiency (PCE) of 20.1% and a fill factor of 78.5%, among the best performance parameters for this bandgap. Importantly, the passivated devices exhibit excellent shelf stability, retaining 92% of their initial performance after 3200 h. Under ambient air conditions at 55 °C, the unencapsulated devices maintained 76% of their initial PCE after 300 h continuous light soaking. The findings represent a significant breakthrough in the development of stable WB‐PSCs for i‐PV applications, with minimized nonradiative losses and enhanced performance.

Artificial photosynthesis system to realize Solar overall water splitting has been regarded as sustainable and renewable solution for energy and environmental issues. While artificial photosynthesis system (efficiency of 12.4%) greatly exceeds efficiency of natural photosynthesis, yet such high efficiency needs multiple, 2 or more light absorbers to achieve, total photovoltage above 1440 mV. In this report, we demonstrate visible light active Single light absorber -2 photons to 1 hydrogen (S2) overall water splitting via photovoltaic-electrochemical system that can be achieved by single junction solar cell, composed with CsPbBr3 (band gap of 2.3 eV) solar cell with open circuit voltage larger than 1600 mV can power up water electrolyzer cell and achieves Solar to hydrogen efficiency of 1.7% with confirmed H2 gas generation. Operating point shows possible STH of 5.0%. This result demonstrates its prospective on efficiency increment (max 12%) and Technoeconomic analysis (modest cost of 5.5 $/kg of hydrogen) in near future, as benchmark for S2 PV-EC system.

The overall energy efficiency (EE) is critical for commercializing promising electrochemical technologies, such as the carbon dioxide reduction reaction (CO2RR). Despite the rapid development of advanced catalysts and reactors for CO2RR, its commercial potential is still hindered by the sluggish oxygen evolution reaction (OER), which causes high cell voltages and low EEs. Herein, we developed a NiOOH@Ni3S2 catalyst on the surface of nickel foam (NF) via an electrochemical surface reconstruction strategy. We observed that the oxidation of glycerol (GLY) to formate (FA) is more thermodynamically favorable than the OER on the developed NiOOH@Ni3S2/NF catalysts. The Ni2+/Ni3+ redox couples within the NiOOH@Ni3S2 heterojunction enhance the charge transfer kinetics between the active sites and adsorbed reaction intermediates, facilitating the highly selective and active generation of FA from GLY oxidation reaction (GOR), with a remarkable Faradaic efficiency (FE) of 94% achieved at 100 mA·cm−2. Comprehensive mechanistic studies identified that the reaction pathway towards FA generation starts from glyceraldehyde intermediates, and glycolate was considered as the key species. Moreover, benefiting from the efficient conversion of CO2 to FA on bismuth nanosheets, the GOR//CO2RR paired electrolysis system realizes a remarkable overall FE of ca. 190% for FA co-production at 160 mA·cm−2 (cathodic FE: 91.25% and anodic FE: 98.70%). This proceeds at a cell voltage of ca. 2.32 V, which is ca. 0.85 V lower than that of OER-assisted CO2RR system at the same current density. This work provides new insights for co-upgrading CO2 and biomass to value-added chemicals.

In this work, we present a high-performance, stable formamidinium lead iodide (FAPI) perovskite solar cell (PSC) achieved through the use of 2,2,6,6-tetramethylpiperidinyloxyl (TEMPO) bulk passivation and rapid photonic annealing. Utilizing flash infrared annealing (FIRA), we fabricated TEMPO-FAPI PSCs with a power conversion efficiency (PCE) exceeding 20%, exceeding the prior state of the art for this process. The TEMPO additive promotes enhanced crystallization dynamics, yielding films with improved homogeneity and reduced defect densities, as confirmed by photoluminescence (PL), profilometry, and positron annihilation lifetime spectroscopy (PALS). Stability testing under ISOS protocols demonstrated that the TEMPO-FAPI devices retained over 90% of their initial PCE after 4,296 h of operational and thermal stress, showing unprecedented longevity for a rapid processing technique. TEMPO's primary effect on passivating grain boundaries and surface defects is evidenced by a significantly reduced non-radiative recombination rate and low defect density, establishing this molecule as a promising additive for scalable, durable FAPI PSC manufacturing.

Hydrogen could be an environmentally friendly option as an energy vector for the future. However, its green production process is expensive, involving water electrolysis, which requires a significant amount of energy. New technologies have been developed to decrease the cost associated with water electrolysis, such as using microbial electrolysis cells (MECs). The integration of power performance enhancing elements into bioelectric systems is of applied interest. As in this work the integration of a photocathode into the microbial electrolysis cell, the energy output increases in theory without needing more reactor space. The microbial electrolysis process requires an additional energy input to overcome the theoretical thermodynamic barrier if any and the involved over- potentials for reasonable rate of hydrogen production. In this work, a microbial electrolysis half-cell was combined with a photoelectrochemical half-cell, so called MPEC (microbial photoelectrochemical cell). The MPEC consisted of a Shewanella oneidensis MR-1 bioanode and a five-layered p-type Cu2O-based photocathode, using lactate as electron donor to produce H2 without any external bias than light of 210 and 700 W m- 2 . The novelty of the work can be summarized in the following points: The use of MPEC for H2 production with a stable and efficient multilayer Cu2O photocathode. The quantification of the anodic, cathodic and global coulombic efficiencies considering the selectivity of lactate to acetate conversion. The electrochemical characterization (I-V curves) of the bioanode and photocathode for the determination of the electrode which limit the current in the process. Proposition of a model to explain the low anodic coulombic efficiencies (7 +/- 2%). In this model lactate may be involved in either a surface reaction at the bioanode (the main reaction producing current) or a bulk aerobic or anaerobic reaction catalysed by planktonic cells (a side reaction that consumes lactate without producing current). This work is of interest of research that aims to integrate multiple processes into bioelectric systems and to use light energy in a direct manner to generate energy vectors such as hydrogen.

Hybrid organic-inorganic perovskite solar cells (PSCs) present a leading thin-film photovoltaic technology with superior solar-to-electric power conversion efficiencies. The most effective compositions, however, contain lead cations, which are toxic and pose environmental hazards. One of the alternatives to lead-based perovskite materials is silver bismuth halide analogues. Here, we present a comprehensive investigation of different silver bismuth iodide compositions by means of density functional theory calculations (DFT) as well as X-ray diffraction, scanning and transmission electron microscopy, X-ray photoelectron spectroscopy, and photoluminescence spectroscopy measurements. Through our combined experimental and theoretical study, we have discovered that silver bismuth iodides possess several intrinsic limitations, such as limited charge transport and localized electronic states, owing to the presence of vacant sites. Such limitations result in moderate solar cell efficiencies, significantly lower than those of lead halide perovskites. However, we suggest the possibility of increasing efficiencies by adding BiCl3 to the precursor solution, yielding one of the highest efficiencies reported for this class of compounds to date. This highlights the potential of compositional engineering for these lead-free solar cell materials.

Achieving industrial electrochemical CO2 reduction necessitates the strategic design of electrocatalysts with high activity, superior selectivity, and excellent stability. Herein, we developed spatially dispersed copper nanocrystals supported by polyaniline (PANI-CuNCs) forelectrochemical CO2 reduction, achieving afaradaic efficiency of 68.6% +/- 2.2% toward methane at-300 mA cm-2. The chelation of the Cu precursor within the oxidized emeraldine base (EB) is crucial for forming isolated CuNCs. The PANI substrate facilitates proton shuttling to Cu(111) sites, enhancing methane production by promoting protonation and reducing *CO coverage. In situ Raman and theoretical calculations show that PANI improves CO2 adsorption and activation by creating a hydrophilic environment, highlighting its potential for industrial CO2 reduction electrocatalysis. Our work introduced a promising strategy that utilizes polymers as substrates to prepare well-dispersed NCs for electrocatalysis, highlighting the potential of such systems in advancing the field of industrial electrochemical CO2 reduction.

Surface reflections and non-radiative recombinations create energy losses in perovskite solar cells (PSCs) by hindering the generation and extraction of carriers. These losses can reduce device efficiency in practical applications as the incident angle of sunlight varies throughout the day. Here we introduce a universal strategy to address this issue by coating glass substrates with highly distributed nanoplates of fluorine-doped tin oxide (NP-FTO). An electron-selective homojunction is then formed with a thin layer of SnO2 deposited by atomic layer deposition covered with SnO2 quantum dots. Systematic mechanistic studies reveal the exceptional ability of NP-FTO to harvest photons omnidirectionally and its beneficial influence on perovskite crystallization. These combined effects result in substantial improvements in the short-circuit current density, open-circuit voltage and fill factor of n–i–p PSCs under wide-angle incident light illumination. The best-performing PSC achieves a remarkable power conversion efficiency (PCE) of 26.4

Monolithic all-perovskite tandem solar cells present a promising approach for exceeding the efficiency limit of single-junction solar cells. However, the substantial open-circuit voltage loss in the wide-bandgap perovskite subcell hinders further improvements in power-conversion efficiency. Here we develop wide-bandgap perovskite films with improved (100) crystal orientation that suppress non-radiative recombination. We show that using two-dimensional perovskite as an intermediate phase on the film surface promotes heterogeneous nucleation along the (100) three-dimensional perovskite facets during crystallization. Preferred (100) orientations can be realized by augmenting the quantity of two-dimensional phases through surface composition engineering, without the need for excessive two-dimensional ligands that otherwise impede carrier transport. We demonstrate an open-circuit voltage of 1.373 V for 1.78 eV wide-bandgap perovskite solar cells, along with a high fill factor of 84.7%. This yields an open-circuit voltage of 2.21 V and a certified power-conversion efficiency of 29.1% for all-perovskite tandem solar cells, measured under the maximum power-point conditions.

Monolithic all-perovskite tandem solar cells present a promising approach for exceeding the efficiency limit of single-junction solar cells. However, the substantial open-circuit voltage loss in the wide-bandgap perovskite subcell hinders further improvements in power-conversion efficiency. Here we develop wide-bandgap perovskite films with improved (100) crystal orientation that suppress non-radiative recombination. We show that using two-dimensional perovskite as an intermediate phase on the film surface promotes heterogeneous nucleation along the (100) three-dimensional perovskite facets during crystallization. Preferred (100) orientations can be realized by augmenting the quantity of two-dimensional phases through surface composition engineering, without the need for excessive two-dimensional ligands that otherwise impede carrier transport. We demonstrate an open-circuit voltage of 1.373 V for 1.78 eV wide-bandgap perovskite solar cells, along with a high fill factor of 84.7

Aqueous zinc-ion batteries have emerged as promising candidates for safe and cost-effective energy storage, yet their performance remains constrained by electrode stability and electrolyte composition. In this study, we investigate the electrochemical behavior of various electrode materials utilizing water-in-salt dual-ion electrolytes. Our findings highlight the critical influence of substrate materials on electrochemical stability, with titanium exhibiting superior anodic stability compared to, e.g., aluminum. Furthermore, we demonstrate the feasibility of LiFePO4 as a positive electrode, revealing a redox potential of 1.17 V vs. Zn2+/Zn in chloride-based electrolyte, which shifts positively with increasing lithium concentration. The observed potential variation with electrolyte composition underscores the need for optimized formulations to enhance the battery performance. Additionally, while LiMnPO4 offers a higher theoretical voltage, its cycling stability remains limited, suggesting that material modifications are necessary. Finally, we highlight the overlooked impact of electrolyte impurities on battery performance, emphasizing the importance of high-purity electrolyte components. These insights contribute to the development of more stable and efficient Zn-ion batteries, paving the way for their practical deployment in energy storage applications.

A deep understanding of how solution-processed solar cells (SSCs) perform under varying temperatures and irradiance is crucial for their optimal design, synthesis, and use. However, current partial spectral characterization, primarily below the band gap wavelengths (λ < λg), limits insights into their full operation. In this work, we expand the current knowledge by providing comprehensive full-spectrum experimental optical characterizations (∼300-2500 nm) and theoretical optical-thermal-electrical analysis for the most common high-efficiency single-junction and tandem organic SSCs (OSCs) and perovskite SSCs (PSCs), including p-i-n OSC, n-i-p OSC, p-i-n PSC, n-i-p mesoscopic PSC, OSC/PSC, and PSC/PSC. By incorporating solar photons above λg in our investigation, we uncover the effects of parasitic absorption (∼300-2500 nm) and conversion losses (λ < λg) on operating temperature and power conversion efficiency (PCE) losses, highlighting the conditions, materials, and optimal architectures for reducing device temperature. These improvements could reduce PCE losses by up to ∼7 times compared to conventional silicon wafer-based solar cells in real-world conditions.