Solar RRL最新文献

Graphitic carbon nitride (g-C₃N₄) has emerged as an attractive metal-free photocatalyst due to its numerous advantages like tunable surface chemistry, Earth abundance, and nontoxicity. Unfortunately, its photocatalytic efficiency has been seriously limited by charge carrier recombination and low reaction dynamics. Here, we report a metal-free BCN photocatalyst achieving highly selective CO₂-to-CH₄ conversion under visible light without requiring any metal cocatalyst. The exfoliated CN nanosheets can enrich the reaction interface with protons to accelerate the protonation of CO intermediate to further produce CH₄. Moreover, B doping not only introduces more reactive defects but also tunes its electronic structure with a more negative conduction band for rapid electron extraction and enhance CO₂-to-CH₄ conversion. Photocatalytic measurements show that CH₄ production rate and CH₄/CO ratio are 24 and 13 times higher than those of bulk CN, respectively. The CH₄ production rate can also reach 130 and 31 times higher than that of few-layer g-C₃N₄ (FL-CN) and Cu/FL-CN, respectively. The electron selectivity toward CH₄ generation on BCN photocatalysts can reach ≈90%. Furthermore, sunlight driving CO₂-to-CH₄ conversion on such BCN photocatalysts has also been demonstrated. This work offers new insights for the design of customized multifunctional 2D materials for solar-driven CO₂ conversion to CH₄.

Recombination centers such as carrier traps due to point defects have long been known as one major limitation to the device efficiency of solar cells. Realizing the origin and the mechanism of the trapping and recombination processes enables a smart design strategy of high-performance photovoltaic (PV) technologies. Thin film Cu(In, Ga)Se₂ solar cells have been commercially used in the PV community due to their high power conversion efficiency, cost-effectiveness, and chemical stability. In this work, we explore the roles of subgap defect states in carrier trapping, in particular effects of Urbach tails in terms of the recombination mechanism, in Cu(In, Ga)Se₂ solar cells via junction-transient spectroscopic techniques. The temperature-dependent Urbach energy (E_U) was extracted from transient photocapacitance (TPC) and transient photocurrent (TPI) measurements. Thermal quenching behavior is observed at ~220 K for slightly different optimum Ga concentrations, with activation energies of 0.2–0.3 eV obtained from the thermal quenching model. The thermal and optical activation processes along the defect states are further interpreted using a 1D configuration coordinate model which takes the electron–phonon interaction into consideration.

Inorganic antimony halides with the general formula A₃Sb₂X₉ have emerged as promising materials for photovoltaic applications due to their low toxicity and high stability. However, achieving high-quality thin-film morphology with this class of materials remains challenging, which adversely affects performance of the solar cell devices. In this work, a facile synthesis procedure is demonstrated for the fabrication of highly crystalline and pinhole-free Cs₃Sb₂Br₉ thin films by introducing a post-annealing process in a solvent-rich atmosphere. Stability of the resulting Cs₃Sb₂Br₉ films on a timescale of 3 days under ambient conditions at 60% relative humidity is demonstrated. Photovoltaic performance of the Cs₃Sb₂Br₉ films is assessed using a standard n-i-p configuration, which produces a power conversion efficiency of 0.173% ± 0.014% under simulated 1 sun irradiation, which represents an improvement compared to the lower efficiency (0.053% ± 0.006%) observed in Cs₃Sb₂Br₉ films prepared using conventional methods.

Extracting uranium from seawater at an ultralow concentration (3.3 ppb) is a promising approach for the sustainable development of nuclear energy, which presents a critical obstacle. Herein, we report a photothermal-promoted extraction strategy by utilizing a self-supporting covalent organic polymer-based sponge (named TpPa-SO₃H@PU sponge) composed of black polyurethane sponge substrate and β-ketoenamine covalent organic polymer with sulfonic acid groups. The adequate water transport induced by photothermal conversion significantly improves the mass transfer of uranyl ions. Compared with the dark condition, a 25.8% increase of uranyl extraction capacity, up to 36.4 mg g⁻¹, is achieved under simulated sunlight irradiation. In 1 L of seawater, 83.8% of uranyl is extracted after exposure to natural sunlight for 48 h. Furthermore, 20 mL of concentrated solution containing 1 ppm uranyl is obtained from 9 L seawater after nine consecutive extraction-elution cycles. These results demonstrate that TpPa-SO₃H@PU sponge holds significant potential for practical uranium extraction from seawater under natural sunlight.

The suboptimal interfacial quality between the perovskite absorption layer and the electron-transport layer constrains the performance of perovskite solar cells. Introducing an interface passivation layer is generally recognized as an effective method for addressing this issue. A uniform passivation film with a large area can be prepared using an evaporation technique. In this study, we designed and fabricated an inorganic CsPbCl₃ passivation layer by the coevaporation of PbCl₂ and CsCl. The evaporated passivator exhibited excellent interface passivation effects and a relatively low thickness sensitivity to device performance. As a result, the open-circuit voltage of perovskite solar cells with a 1.68 eV perovskite absorber was improved by nearly 100 mV, and the device efficiency achieved was 21.84%, ranking as the highest efficiency based on the hybrid evaporation-solution method. The proposed passivation approach has potential applications in large-area perovskite solar cells.

Perovskite solar cells (PSCs) have emerged as a promising photovoltaic technology due to their remarkable efficiency advancements. However, their commercialization is hindered by stability challenges, including sensitivity to environmental conditions and a critical degradation mechanism known as potential-induced degradation (PID). PID can significantly impair PSC performance within hours under operational conditions. This study investigates PID in 48 triple-cation p-i-n PSCs over 313 h in an inert environment, excluding additional stressors like moisture and oxygen. The PID-stressed devices degraded to 79% of their initial efficiency, primarily driven by losses in short-circuit current density. Time-of-flight secondary ion mass spectroscopy revealed sodium ion migration from soda-lime glass substrates into the perovskite layer. Interestingly, photoluminescence and X-ray diffraction analyses detected no measurable differences between PID-stressed and reference devices, contradicting prior literature that associates PID with perovskite segregation and decomposition. These findings challenge the conventional understanding of PID, suggesting that environmental factors such as oxygen and moisture might exacerbate degradation effects. This work provides critical insights into the intrinsic mechanisms of PID under controlled conditions and highlights the need for further research into the interplay between PID and environmental stressors to guide the development of more stable PSC technologies.

Photocatalytic hydrogen production is regarded as one of the most promising approaches for solar energy utilization due to its reliance on renewable energy sources, environmental friendliness, and generation of clean energy. In this field, Mn_0.5Cd_0.5S demonstrates considerable potential, but its severe stacking issue and insufficient exposure of active sites restrict its application. Although Mn_0.5Cd_0.5S demonstrates considerable potential, its severe stacking issue and insufficient exposure of active sites restrict its application. In this research, by combining Mn_0.5Cd_0.5S with dodecahedral ZIF-67 and optimizing the interfacial electronic structure, a uniform distribution of Mn_0.5Cd_0.5S on the surface of ZIF-67 was successfully accomplished. Synthesis of composite materials effectively mitigated the agglomeration phenomenon of Mn_0.5Cd_0.5S and constructed an S-scheme heterostructure of Mn_0.5Cd_0.5S/ZIF-67. The resulting composite achieved a hydrogen yield of 677.4 μmol in a lactic acid system, 6.8 times higher than that of pure Mn_0.5Cd_0.5S. This notable enhancement is attributed to the increased specific surface area of the composite, facilitating greater exposure of the active sites and improving charge transfer efficiency. In situ X-ray photoelectron spectroscopy analysis revealed the underlying electron transfer mechanism, while EPR studies confirmed the enhanced redox capacity of the composite, further supporting its superior performance in hydrogen production. This research offers new insights into morphology and interface engineering for Mn_0.5Cd_0.5S-based materials.

Sn-perovskites are considered a suitable alternative to toxic Pb-perovskites due to their low toxicity and optimum optoelectronic properties. However, high-efficiency Sn-based perovskite solar cells (Sn-PSCs) typically use poly (3,4-ethylenedioxythiophene):polystyrene sulfonic acid (PEDOT:PSS) as a hole-transporting material (HTM), which limits their stability due to its acidic nature. This study introduces SnO_X nanocrystals, synthesized through a synproportionation reaction of Sn⁴⁺ with Sn⁰ under mild conditions, as a replacement for PEDOT:PSS. X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy analyses revealed that the Sn⁰ reduces Sn⁴⁺ by 38% and elevates the highest occupied molecular orbital to –5.70 eV, close to PEDOT:PSS, enabling HTM behavior. The perovskite films on SnO_X exhibit improved grain size and crystallinity compared to PEDOT:PSS. The resulting SnO_X-based Sn-PSCs achieved a power conversion efficiency of 11.11%. They retained 90% of their efficiency after 1000 h of maximum power point tracking, indicating superior stability over PEDOT:PSS-based devices.

Printable planar carbon electrodes present a cost-effective and highly promising alternative to thermally evaporated metals, serving as the rear contact for stable perovskite solar cells (PSCs). However, the power conversion efficiencies (PCEs) of the carbon-based PSCs (C-PSCs) are notably lower compared to those of state-of-the-art PSCs. The inferior contact between the carbon electrode and the underlying layer contributes to the performance loss. Here, we developed scalable doctor-bladed carbon electrode by simultaneously incorporating 4 wt% carbon black and utilizing toluene (TLE) solvent engineering to a commercial carbon paste, resulting in improved flexibility and conductivity while yielding reduction of resistivity by 50% measured via a 4-point probe. Consequently, the carbon sheet can efficiently adhere the underlying hole-transporting layer by a simple pressing technique, significantly boosting charge transfer across the interface. The TLE device achieves a champion PCE of 15.77% with an ultralow hysteresis index (HI) of 0.027, compared to the solvent-free device which has a HI of 0.176. The developed carbon-based device exhibits notably improved long-term stability when subjected to dark conditions and 40-50% RH, sustaining 82% of its initial efficiency after 24 days without encapsulation with minimal declines in J_sc and V_oc.

A simple diphenylamine-based hole transporting material V1553 was synthesized and incorporated into a perovskite solar cell, which showed remarkable power conversion efficiency close to 23%. The investigated HTM was synthesized via one-step catalyst-free condensation reaction from commercially available and extremely cheap starting reagents, resulting in a fractional cost of the final product compared to the commercial spiro-OMeTAD. This material promises to be a viable p-type organic semiconductor to be employed in the manufacturing of perovskite solar modules.