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Perovskite lattice distortion induced by residual tensile strain from the thermal expansion mismatch between the electron‐transporting layer (ETL) and perovskite film causes a sluggish charge extraction and transfer dynamics in all‐inorganic CsPbBr3 perovskite solar cells (PSCs) because of their higher crystallization temperatures and thermal expansion coefficients. Herein, the interfacial strain is released by fabricating a WS2/CsPbBr3 van der Waals heterostructure owing to their matched crystal lattice structure and the atomically smooth dangling bond‐free surface to act as a lubricant between ETL and CsPbBr3 perovskite. Arising from the strain‐released interface and condensed perovskite lattice, the best device achieves an efficiency of 10.65 % with an ultrahigh open‐circuit voltage of 1.70 V and significantly improved stability under persistent light irradiation and humidity (80 %) attack over 120 days. [ABSTRACT FROM AUTHOR]

Vacancy enriched electrocatalysts are crucial in enhancing the catalytic activity for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) through a defect engineering. Herein, oxygen vacancies enriched Co 3 O 4 nanoflowers with single layer porous structures are made to study their catalytic activity toward water splitting. The as-synthesized defects enriched Co 3 O 4 presents flowers-like nanostructures and possesses high specific surface area (84 m2 g−1) with uniform pore size (4 nm). On behalf of the unique morphology and electronic structure, the Co 3 O 4 nanoflowers display enhanced HER and OER performances compared with commercial Co 3 O 4 nanoparticles (∼50 nm). In addition, it still presents good catalytic without remarkably decay in potential over 9 days. • Oxygen vacancies enriched Co 3 O 4 nanoflowers with single layer porous structures are synthesized. • The as-synthesized electrocatalyst displays superior water splitting performances. • The enhanced performances could be attributed to the unique morphology and electronic structure. • The catalytic activity is maintained for at least 9 days without remarkably decay. [ABSTRACT FROM AUTHOR]

Improved charge extraction and wide spectral absorption promote power conversion efficiency of perovskite solar cells (PSCs). The state‐of‐the‐art carbon‐based CsPbBr3 PSCs have an inferior power output capacity because of the large optical band gap of the perovskite film and the high energy barrier at perovskite/carbon interface. Herein, we use alkyl‐chain regulated quantum dots as hole‐conductors to reduce charge recombination. By precisely controlling alkyl‐chain length of ligands, a balance between the surface dipole induced charge coulomb repulsive force and quantum tunneling distance is achieved to maximize charge extraction. A fluorescent carbon electrode is used as a cathode to harvest the unabsorbed incident light and to emit fluorescent light at 516 nm for re‐absorption by the perovskite film. The optimized PSC free of encapsulation achieves a maximum power conversion efficiency up to 10.85 % with nearly unchanged photovoltaic performances under 80 %RH, 80 °C, or light irradiation in air. [ABSTRACT FROM AUTHOR]

Improved charge extraction and wide spectral absorption promote power conversion efficiency of perovskite solar cells (PSCs). The state‐of‐the‐art carbon‐based CsPbBr3 PSCs have an inferior power output capacity because of the large optical band gap of the perovskite film and the high energy barrier at perovskite/carbon interface. Herein, we use alkyl‐chain regulated quantum dots as hole‐conductors to reduce charge recombination. By precisely controlling alkyl‐chain length of ligands, a balance between the surface dipole induced charge coulomb repulsive force and quantum tunneling distance is achieved to maximize charge extraction. A fluorescent carbon electrode is used as a cathode to harvest the unabsorbed incident light and to emit fluorescent light at 516 nm for re‐absorption by the perovskite film. The optimized PSC free of encapsulation achieves a maximum power conversion efficiency up to 10.85 % with nearly unchanged photovoltaic performances under 80 %RH, 80 °C, or light irradiation in air. [ABSTRACT FROM AUTHOR]

The all‐inorganic CsPbBr3 perovskite solar cell (PSC) is a promising solution to balance the high efficiency and poor stability of state‐of‐the‐art organic–inorganic PSCs. Setting inorganic hole‐transporting layers at the perovskite/electrode interface decreases charge carrier recombination without sacrificing superiority in air. Now, M‐substituted, p‐type inorganic Cu(Cr,M)O2 (M=Ba2+, Ca2+, or Ni2+) nanocrystals with enhanced hole‐transporting characteristics by increasing interstitial oxygen effectively extract holes from perovskite. The all‐inorganic CsPbBr3 PSC with a device structure of FTO/c‐TiO2/m‐TiO2/CsPbBr3/Cu(Cr,M)O2/carbon achieves an efficiency up to 10.18 % and it increases to 10.79 % by doping Sm3+ ions into perovskite halide, which is much higher than 7.39 % for the hole‐free device. The unencapsulated Cu(Cr,Ba)O2‐based PSC presents a remarkable stability in air in either 80 % humidity over 60 days or 80 °C conditions over 40 days or light illumination for 7 days. [ABSTRACT FROM AUTHOR]

The all‐inorganic CsPbBr3 perovskite solar cell (PSC) is a promising solution to balance the high efficiency and poor stability of state‐of‐the‐art organic–inorganic PSCs. Setting inorganic hole‐transporting layers at the perovskite/electrode interface decreases charge carrier recombination without sacrificing superiority in air. Now, M‐substituted, p‐type inorganic Cu(Cr,M)O2 (M=Ba2+, Ca2+, or Ni2+) nanocrystals with enhanced hole‐transporting characteristics by increasing interstitial oxygen effectively extract holes from perovskite. The all‐inorganic CsPbBr3 PSC with a device structure of FTO/c‐TiO2/m‐TiO2/CsPbBr3/Cu(Cr,M)O2/carbon achieves an efficiency up to 10.18 % and it increases to 10.79 % by doping Sm3+ ions into perovskite halide, which is much higher than 7.39 % for the hole‐free device. The unencapsulated Cu(Cr,Ba)O2‐based PSC presents a remarkable stability in air in either 80 % humidity over 60 days or 80 °C conditions over 40 days or light illumination for 7 days. [ABSTRACT FROM AUTHOR]

The all‐inorganic CsPbBr3 perovskite solar cell (PSC) is a promising solution to balance the high efficiency and poor stability of state‐of‐the‐art organic–inorganic PSCs. Setting inorganic hole‐transporting layers at the perovskite/electrode interface decreases charge carrier recombination without sacrificing superiority in air. Now, M‐substituted, p‐type inorganic Cu(Cr,M)O2 (M=Ba2+, Ca2+, or Ni2+) nanocrystals with enhanced hole‐transporting characteristics by increasing interstitial oxygen effectively extract holes from perovskite. The all‐inorganic CsPbBr3 PSC with a device structure of FTO/c‐TiO2/m‐TiO2/CsPbBr3/Cu(Cr,M)O2/carbon achieves an efficiency up to 10.18 % and it increases to 10.79 % by doping Sm3+ ions into perovskite halide, which is much higher than 7.39 % for the hole‐free device. The unencapsulated Cu(Cr,Ba)O2‐based PSC presents a remarkable stability in air in either 80 % humidity over 60 days or 80 °C conditions over 40 days or light illumination for 7 days. [ABSTRACT FROM AUTHOR]

The severe interface charge recombination caused by the large energy difference between perovskite material and carbon electrode significantly limits the further performance improvement of the all-inorganic perovskite solar cells (PSCs). We apply innovatively multilayer of quaternary Ag-In-Ga-S (AIGS) quantum dots (QDs) with cascade-like valence bands as hole-transport materials to assemble all-inorganic PSCs, and the resultant all-inorganic PSCs exhibit a power conversion efficiency (PCE) of 8.46%, which is enhanced by 20.9% in comparison with 7% for the pristine device. The high performance of the PSCs indicates that sequential layers of AIGS QDs with cascade-like energy levels can facilitate the charge separation, reduce the barrier the holes crossing and suppress the charge recombination. Stack of QDs with cascade-like energy levels provide solution-processed PSCs with a new method to enhance device performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Residual strain is released via in-situ compensation by phase transformation strain. • The addition of DMSO optimizes PbBr 2 crystallization kinetics and film morphology. • CsPbBr 3 film quality is improved with 2.91 μm-grain size and reduced defect density. • The unsealed device achieves a best PCE of 10.11% and high moisture-heat stability. The presence of defects and residual tensile strain in perovskites has a significant and deleterious impact on the efficiency and stability of all-inorganic perovskite solar cells (PSCs). Here, dimethyl sulfoxide (DMSO) with strong polarity and high boiling point is introduced into the PbBr 2 precursor to delay the crystallization of PbBr 2 , leading to the formation of high-quality PbBr 2 films by delaying the solution reaching supersaturation. The formation of PbBr 2 (DMSO) adduct facilitates the complete reaction of PbBr 2 with CsBr via intramolecular exchange, thus preventing the formation of impurity phases such as CsPb 2 Br 5. As a result, the defect density of CsPbBr 3 films decreased by 33% due to the improved phase purity, thicker films, larger grain sizes, and reduced grain boundaries. The small porosity of PbBr 2 film combined with a more complete phase-conversion process results in an expanded perovskite film that experiences compressive strain, effectively compensating for the tensile strain generated during annealing and thereby achieving the goal of strain relaxation. The optimized DMSO-based device, which exhibits compressive strain and minimal defects, achieves a remarkable efficiency of 10.11% with an open-circuit voltage of up to 1.611 V. Additionally, the unencapsulated PSC demonstrates excellent stability under 80% relative humidity and 80 °C over 30 days. [ABSTRACT FROM AUTHOR]

Graphical abstract Co/Se and Ni/Se nanocomposite films deposited on FTO glasses via magnetron sputtering are used as counter electrodes in dye-sensitized solar cells, yielding a maximized power conversion efficiency of 6.43%. Highlights: • Co/Se and Ni/Se nano-films are prepared by magnetron sputtering method. • The as-prepared films are employed as CEs for DSSCs. • The DSSC with Co/Se CE delivers a PCE of 6.43%. Abstract Dye-sensitized solar cells are promising solutions to energy and environmental problems. By addressing the high cost of preferred platinum counter electrode, Co/Se and Ni/Se nanocomposite counter electrodes are prepared by magnetron sputtering targets onto fluorine-doped tin oxide glass for dye-sensitized solar cell applications. The binary nanocomposite counter electrodes exhibit superior electrocatalytic activity toward I 3 − reduction compared to pure Ni, Se and Co electrodes. In particular, the dye-sensitized solar cell based on Co/Se counter electrode achieves a power conversion efficiency of 6.43%, which is much higher than 0.87%, 2.91%, 3.77% and 5.23% for Ni, Se, Co and Ni/Se solar cells, respectively. The preliminary results demonstrate it is a promising strategy to prepare robust counter electrodes by magnetron sputtering technique for dye-sensitized solar cells. [ABSTRACT FROM AUTHOR]

Abstract The development of weather-independent photovoltaics is a promising strategy for persistently generating electricity in daytime and night. Herein we build a category of multi-energy integrated bifacial solar cells by making long persistence phosphors (LPPs) tailored transparent counter electrodes. The optimized cell with green-emitting transparent polypyrrole-graphene/PtCo achieves a maximized power conversion efficiency of 8.59% under a simulated sun irradiation (100 mW cm−2, air mass 1.5 global) as well as a dark efficiency of 29.68% when ceasing solar illumination. Moreover, the newly launched photovoltaics can persistently generate power lasting for hours in the dark environments. The current work demonstrates a predictable application of photoelectric engineering for persistent energy harvesting free of sun illumination in future. Graphical abstract Image 1 Highlights • Bifacial DSSCs are made by LPP tailored PPy-graphene/PtCo CE. • LPP releases fluorescence to persistently excite dyes when ceasing sunlight illumination. • The DSSCs can persistently generate electricity in the dark. • The newly launched DSSCs yield maximized dark efficiency as high as 29.68%. [ABSTRACT FROM AUTHOR]

Abstract The co-sensitization of mesoscopic TiO 2 anode is a promising solution to wide-spectra dye-sensitized solar cells (DSSCs) with improved power conversion efficiency. Quantum dots are featured with tunable bandgaps, small sizes and high absorption coefficients, therefore they are always combined with state-of-the-art organic dyes for co-sensitized solar cells. We present here the sonochemistry-assisted synthesis of hybrid black/red phosphorus quantum dots (BP/RPQDs) for DSSC applications. The preliminary results demonstrate that hybrid BP/RPQDs have prolonged recombination lifetime of photogenerated carriers and light-response from ultraviolet to visible and even near-infrared (NIR) region. Upon assembly into liquid-junction DSSCs, the devices with BP/RPQDs-only and BP/RPQDs-N719 co-sensitizer achieve efficiencies of 0.12% and 8.02% in comparison with 7.60% for N719-only solar cell. Using photofluorescent photoanode from mesoscopic TiO 2 and long-persistence phosphor (LPP), the new-typed DSSC presents persistent power generation performances after ceasing simulated sunlight irradiation. Graphical abstract Image 1 Highlights • Hybrid BP/RPQDs are made by a sonochemistry-assisted method. • The hybrid BP/RPQDs show wide light-response in light-harvesters of DSSCs. • BP/RPQDs-only solar cells show a PCE of 0.12%. • An efficiency as high as 8.02% is achieved for BP/RPQDs tailored DSSCs. [ABSTRACT FROM AUTHOR]

Perovskite-structured cesium lead bromide (CsPbBr3) halide provides new opportunities for promoting the commercialization of perovskite solar cells (PSC) due to its high carrier mobility and light absorption coefficient as well as remarkable environmental stability at high humidity and high temperatures. Herein, all-carbon electrodes from multi-walled carbon nanotubes (MWCNT) and carbon black (CB) were prepared for all-inorganic CsPbBr3 PSCs with the configuration of FTO/c-TiO2/m-TiO2/CsPbBr3/carbon. The as-prepared electrodes were free of hole-transporting layers and precious metals. The work function and electrical conductivity of the carbon electrode were tuned by changing the MWCNT/CB ratio to reduce charge recombination at the perovskite/carbon interface. The optimal all-inorganic PSC achieves a maximum power conversion efficiency of 7.62% using the MWCNT (75 wt%)/CB (25 wt%) electrode in comparison with 6.24% for the pure MWCNT-based device. Upon persistent attack by 80% RH in air atmosphere, the solar cell retains 95% of its initial efficiency over 1100 h. [ABSTRACT FROM AUTHOR]

Abstract High-temperature supercapacitors with enhanced charge transportation and capacitances are promising to meet specific requirements for underhood automotive component, oil drilling, military and space applications. However, state-of-the-art supercapacitors are always operated at room temperature due to the thermal instability of the hydrous electrolytes and organic separators. Herein, we present the fabrication of a high-temperature supercapacitor tailored by a ceramic NiO/ZrO 2 separator. This supercapacitor has a working temperature up to 140 °C, a capacitance of 342 F g-1 at current density of 2 A g−1 and good cycling stability over 2000 cycles. The experimental realization of physical proof-of-concept high-temperature supercapacitors may provide new opportunities for markedly improving the capacity of energy storage systems. Graphical abstract Image 1 Highlights • The ceramic NiO/ZrO 2 membranes are made to replace polymer separators. • The ceramic membranes are applied for high-temperature supercapacitors. • A KOH glycerin solution is utilized as a high-temperature electrolyte. • The device yields a maximized capacitance up to 342 F g-1 at 140 °C. • The high-temperature supercapacitors are stable at 140 °C over 2000 cycles. [ABSTRACT FROM AUTHOR]

Abstract Interfacial charge recombination seriously drags efficiency enhancement of all-inorganic perovskite solar cells (PSCs) because of large energy-level differences. Although CsPbBr 3-x I x light-harvesters markedly reduce interfacial charge recombination, the long-term stability of solar cell devices is still unsatisfactory to meet practical requirements. Here we present the improved charge extraction by setting an intermediated energy-level at CsPbBr 3 /carbon interface with colorful CsSnBr 3-x I x quantum dots (QDs). The charge extraction is maximized by tuning Br:I ratio, yielding a power conversion efficiency as high as 9.13% for CsSnBr 2 I QDs-tailored CsPbBr 3 solar cell. Moreover, all the devices show high stability in 80%RH or 80 °C over 720 h. The interfacial decoration of all-inorganic perovskite solar cells by lead-free perovskite QDs provides new opportunities of enhancing solar cell efficiency and reducing environmental impacts. Highlights • PQDs with tunable bandgaps are synthesized to modify CsPbBr 3 /carbon interface. • An intermediate energy level is set at CsPbBr 3 /carbon interface to extract holes. • The electron-hole recommendation is markedly restricted. • A maximized PCE of 9.13% is achieved for the PQDs tailored inorganic PSC. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Abstract Renewable energy conversion has become one of the major strategies to solve energy crisis and environmental pollution. Tremendous energy is released during the raining process, however rain energy is always considered as a waste energy without further utilization. We present here experimental realization of physical proof-concept rain-response electrodes from polypyrrole (PPy), PPy-graphene and PPy-graphene/PtCo for rain energy harvest. By obeying charging/discharging mechanism of cation (rain)/electron (electrode) electrical double-layer (EDL) pseudocapacitances at rainwater/electrode interfaces, periodical current and voltage signals are produced under the stimulation of simulated rain droplets. The energy conversion device made from PPy-graphene/PtCo achieves a maximized peak current of 4.91 μA/droplet, a peak voltage of 320.62 μV/droplet, yielding a power of 1161.38 pW/droplet. The results demonstrate that the improved current and voltage outputs are highly dependent on increased electron concentration at electrode surface. This work may extend our knowledge to advanced energy conversion devices for waste energy harvest. Graphical abstract A rain-responsive polypyrrole-graphene/PtCo electrode is made to harvest rain. Image 1 Highlights • Electron-enriched electrodes are utilized to harvest rain energy. • The electrodes are made with polypyrrole (PPy), PPy-graphene or PPy-graphene/PtCo. • The electrodes achieve maximized current of 4.91 μA and voltage of 320.62 μV. • Electrical signals are improved by increasing electron concentration of electrodes. [ABSTRACT FROM AUTHOR]

We present here the successful fabrication of core–shell constructed CdZnSe@ZnSe colloidal alloy quantum dots with tunable optical properties using a hot-injection method, demonstrating great potential in photovoltaic devices. Upon employment as charge extraction materials in all-inorganic perovskite solar cells, an enhanced power conversion efficiency up to 8.65% has been achieved arising from the boosted charge transfer dynamics. [ABSTRACT FROM AUTHOR]

Rain energy harvest by a cost-effective technique is promising to increase renewable energy production. In this work, we demonstrate experimental realization of a category of film-type converter tailored with polyaniline (PANi) or PANi-graphene complex films to harvest rain energy. According to the charging/discharging processes of cation/electron pseudo-capacitances at rain/film interfaces, these converters produce maximized current and voltage of 3.80 μA/droplet and 85.01 μV/droplet, respectively. The resultant electricity outputs can be further enhanced by enriching electron concentration at the surfaces of these materials. Furthermore, these rain-enabled converters have good long-term stability under persistent stimulus by raindrops. This work may provide new opportunities of harvesting waste renewable energies from nature. [ABSTRACT FROM AUTHOR]

Development of self-powered monoelectrodes for clean energy harvest is a promising solution to meet the growing energy demands for modern electronic device applications. To address this issue, a category of self-powered monoelectrodes are made from cost-effective graphene composite films to harvest rain energy. Periodic current and voltage signals are recorded under rain stimulation to evaluate their rain-to-electricity efficiency. The mechanism behind rain energy harvest arises from charging/discharging cycles of electric π-electron (graphene)|cation (rain) double-layer pseudocapacitances at graphene film/raindrop interface. The maximized current of 2.15 μA/raindrop, voltage of 129.83 μV/raindrop and power of 295.48 pW/raindrop are yielded in the optimized conversion devices. The present work may provide new insights on harvesting waste energies in rain-enriched regions by designing electron-enriched monoelectrodes. [ABSTRACT FROM AUTHOR]

Graphical abstract The TiO 2 /CsPbBr 3 and CsPbBr 3 /carbon interfaces of all-inorganic PSC are modified by CQDs and RPQDs to extract electrons and holes, respectively. Highlights • All-inorganic CsPbBr 3 solar cells are made by a multi-step solution-processable method. • Intermediate energy levels are set at TiO 2 /CsPbBr 3 and CsPbBr 3 /carbon interfaces. • CQDs and RPQDs are used to extract electrons and holes, respectively. • The optimized inorganic PSC yields an efficiency of 8.20% and improved stability. Abstract Perovskite-structured cesium lead bromide (CsPbBr 3) halide is a rising light harvester for perovskite solar cell applications due to its high absorption coefficient and stability upon heat and humidity attacks. However, the serious electron-hole recombination arising from large interfacial energy differences has markedly limited charge extraction for enhanced photovoltaic performances. Herein, we systematically study fast charge extraction at TiO 2 /CsPbBr 3 and CsPbBr 3 /carbon interfaces by setting intermediate energy levels with carbon quantum dots and red phosphorus quantum dots, respectively. The interfacial radiative or trap-dominant recombination can be significantly suppressed owing to the boosted charge transfer ability as well as the passivation effect by incorporating the carbon quantum dots and red phosphorus quantum dots into solar cells. Finally, the optimal perovskite solar cell device achieves a maximized power conversion efficiency of 8.20% under one sun illumination in comparison with 6.37% for quantum dots-free solar cell. Moreover, the efficiency is reduced by only 3% upon persistent attack with 80% relative humidity over 1000 h, suggesting a good environmental tolerance to boost the commercialization. [ABSTRACT FROM AUTHOR]

Development of high-performance light harvesters is a persistent goal for mesoscopic solar cells. In the current work, lead-free CH 3 NH 3 SnBr 3-x I x (x = 0–3) perovskite quantum dots (QDs) are made by integrating Br − ions into host crystal structure. Through tuning Br/I ratio, these perovskite-structured QDs are highlighted with tunable optical bandgaps. When applied as light harvesters for mesoscopic solar cell applications, the devices yield reasonable power conversion efficiency and rapid start-up behaviors. An efficiency of 8.79% is achieved for CH 3 NH 3 SnBr 3-x I x QDs and N719 co-sensitized mesoscopic solar cells. [ABSTRACT FROM AUTHOR]

Dye-sensitized solar cells (DSSC) have narrow spectral response and serious electron-hole recombination, which are two burdens for photovoltaic performance enhancement. In order to make high-performance DSSCs featured by wide-spectral absorption and fast charge extraction, we present here experimental realization of co-sensitization of nitrogen (N)-doped carbon quantum dots (N-CQDs) with N719 dye. Arising from up-conversion and hole extraction behaviors of N-CQDs, a maximized power conversion efficiency (PCE) as high as 9.29% under one sun illumination is achieved for N 300 -CQDs/N719 co-sensitized DSSC in comparison with 8.09% for N 300 -CQDs-free device. Due to light storing and emitting characteristics of photofluorescent long persistence phosphors in mesoscopic titanium dioxide/long persistence phosphor ( m -TiO 2 /LPP) photoanode, electricity is persistently generated when ceasing sunlight illumination. This work is far from optimization, but the physical proof-of-concept co-sensitization and fast charge extraction may remarkably widen light-response windows and promote electron-hole separation for advanced photovoltaic devices. [ABSTRACT FROM AUTHOR]

Photovoltaics are regarded as the promising solution to resolve energy and environmental problems owing to their high power conversion efficiency and zero emissions. However, the narrow-spectra absorption range and serious recombination reactions at electrode/electrolyte interfaces are two major drawbacks for high-performance solar cells. Herein, a new way of synthesizing organic-inorganic hybrid CH 3 NH 3 PbX 3 (X = Cl, Br or I) perovskite quantum dots (PQDs) is demonstrated by dropping perovskite precursor solution into anhydrous toluene. After a systematic study, the results demonstrate that the energy levels of PQDs can be tuned through optimizing the stoichiometric ratio of halide ions, showing good optical properties for photovoltaic applications. A quasi-solid-state sensitized solar cell with configuration of FTO/ m -TiO 2 /PQDs/dye/long persistence phosphor/gel electrolyte/Pt/FTO is fabricated, yielding an impressive power conversion efficiency as high as 7.91%, which is higher than 7.26% for referenced device free of PQDs. The improved performances are mainly attributed to the increased light absorption as well as reduced recombination upon the incorporation of PQDs and long persistence phosphor into devices. [ABSTRACT FROM AUTHOR]

The development of weather-independent photovoltaics is a persistent goal for energy technique. Herein we develop a category of hybridized dye-sensitized solar cells (DSSCs) from cost-effective poly(3,4-ethylenedioxythiophene) (PEDOT) derivate counter electrodes and mesoscopic titanium dioxide/long persistence phosphors ( m -TiO 2 /LPPs) composite photoanodes. Using the solar energy storage and emission performances of LPP phosphors, the final m -TiO 2 /LPPs photoanodes are demonstrated to store unabsorbed incident light and to persistently emit monochromatic light for re-exciting photosensitizers. The optimized photovoltaics yield a maximized power conversion efficiency of 10.07% under simulated sunlight irradiation (100 mW cm −2 , air mass 1.5 global) and durable energy output lasting for hours when ceasing solar illumination. The application of m -TiO 2 /LPP photoanodes in the hybridized DSSCs provides new opportunities of making multi-energy integrated photovoltaics for persistent power generation free of sun illumination. [ABSTRACT FROM AUTHOR]

Bifacial dye-sensitized solar cells (DSSCs) are regarded as promising photovoltaics to harvest solar energy from both front and rear sides because of their significantly increased total power outputs. Transparent counter electrodes (CEs) with cost-effectiveness and high electrocatalytic activity are crucial to make these high-performance bifacial devices. Herein, a category of transparent CEs from ternary alloys [(CoM) 0.85 Se, M = Ni, Ru, Fe] are synthesized by a mild solution method. Upon careful optimization on optical behaviors, electrocatalytic activity and photovoltaic performances, the bifacial DSSCs with (CoNi) 0.85 Se, (CoRu) 0.85 Se, (CoFe) 0.85 Se CEs achieve front power conversion efficiencies of 9.14%, 8.09%, 7.58% and rear efficiencies of 3.86%, 3.31%, 3.51% in comparison with 6.72% and 3.16% for state-of-the-art Pt CE based solar cell, respectively. Moreover, these bifacial DSSCs devices display high multiple on/off capability and relatively good stability. [ABSTRACT FROM AUTHOR]

We present here the construction of all-inorganic bifacial CsPbBr3 perovskite solar cells to harvest solar energy from both sides. The quantum dot modified bifacial device achieves front and rear efficiencies of 7.55% and 7.44% under one sun illumination, respectively. The solar cell without encapsulation retains around 95% of the initial efficiency at 60% RH over a period of 1000 h. [ABSTRACT FROM AUTHOR]

Perovskite-structured CsPbBr 3 halide is an emerging light-harvester for all-inorganic solar cells due to its superior stability against moisture and heat. However, the wide bandgap of CsPbBr 3 (2.3 eV) calls for serious charge recombination and low efficiency in its photovoltaics. We present here all-inorganic CsPbBr 3 perovskite solar cells (PSCs) by modifying TiO 2 /CsPbBr 3 and CsPbBr 3 /carbon interfaces with carbon quantum dots (CQDs) and phosphorus quantum dots (PQDs), respectively. The electron and hole extractions are markedly enhanced by setting intermediate energy levels, and the optimized PSC achieves a power conversion efficiency of 7.93% in comparison with 6.05% for the device free of CQDs and PQDs. Moreover, the unsealed PSCs are highlighted by long-term stability in high humidity over 1400 h. This work may provide new opportunities of promoting charge extraction at CsPbBr 3 /charge-transporting material interfaces. [ABSTRACT FROM AUTHOR]

Bifacial light-harvesting technology is regarded as one effective strategy to enhance the power output of photovoltaic devices, in which the transparent electrode is crucial to determine the power conversion efficiency when illuminated from rear side. To date, the efficiency enhancement of the state-of-the-art bifacial mesoscopic solar cells is mainly focused on the rational design of high catalytic counter electrode without sacrificing the transparency. The cell performance maximum through increasing electron density at counter electrode surface to enhance its catalytic ability is still a challenging problem. In the current work, bi-tandem carbon quantum dots are made to tailor transparent CoSe counter electrode for bifacial dye-sensitized solar cells, achieving a maximized front power conversion efficiency of 8.54% and a rear efficiency of 6.55% in comparison with 7.87% and 5.03% for carbon quantum dots-free device, respectively. The mechanism behind this increment is stemmed from the photo-excited electrons of bi-tandem carbon quantum dots and therefore realizing the electron accumulation on the counter electrode surface. [ABSTRACT FROM AUTHOR]

Carbon quantum dots (CQDs) are a new class of carbon nanomaterials that have emerged recently and have garnered much interest in many fields. We present here a simple hydrothermal conversion from Gelidium amansii powders, a type of red algae, to cubic carbon quantum dots (CCQDs). The synthesized CCQDs exist in average size of 4.87 nm, and have fluorescence quantum yield of 3.12% as well as good water solubility. CCQDs are applied as light-harvesters for mesoscopic solar cells. The solar cell tailored with CCQDs/N719 yields a maximized power conversion efficiency of 8.68% in comparison to 7.83% for N719-only device. We anticipate that our results will be a vital point for further research, leading to high-performance next-generation solar cell. [ABSTRACT FROM AUTHOR]

Energy harvesting from nature is promising to address the issues of energy crisis and environmental pollution. In the current work, we present experimental realization of a category of film-type rain energy converters from conductive polymer (CP)/PtCo hybrids including polypyrrole (PPy)/PtCo, polyaniline (PANi)/PtCo and poly(3,4-ethylenedioxythiophene) (PEDOT)/PtCo to yield electricity in rainy atmosphere. The optimized CP/PtCo hybrid generates maximum current of 2.06 μA/droplet and voltage of 97.43 μV/droplet, respectively. Although this work is far from optimization, these film-type rain energy converters may markedly elevate signal values and further electricity outputs by being enriched electrons of film surface, and therefore make them possible to generate electricity in areas with abundant rainfall but insufficient solar energy resources, and power supply in the reefs and offshore navigation. The reasonable electricity performances extend our knowledge for all-weather electricity generation platforms. [ABSTRACT FROM AUTHOR]

Abstract: Moisture is the worst enemy for state‐of‐the‐art perovskite solar cells (PSCs). However, the flowing water vapor within nanoporous carbonaceous materials can create potentials. Therefore, it is a challenge to integrate water vapor and solar energies into a single PSC device. We demonstrate herein all‐inorganic cesium lead bromide (CsPbBr3) solar cells tailored with carbon electrodes to simultaneously harvest solar and water‐vapor energy. Upon interfacial modification and plasma treatment, the bifunctional PSCs yield a maximum power conversion efficiency up to 9.43 % under one sun irradiation according to photoelectric conversion principle and a power output of 0.158 μW with voltage of 0.35 V and current of 0.45 μA in 80 % relative humidity through the flowing potentials at the carbon/water interface. The initial efficiency is only reduced by 2 % on exposing the inorganic PSC with 80 % humidity over 40 days. The successful realization of physical proof‐of‐concept multi‐energy integrated solar cells provides new opportunities of maximizing overall power output. [ABSTRACT FROM AUTHOR]

Abstract: Moisture is the worst enemy for state‐of‐the‐art perovskite solar cells (PSCs). However, the flowing water vapor within nanoporous carbonaceous materials can create potentials. Therefore, it is a challenge to integrate water vapor and solar energies into a single PSC device. We demonstrate herein all‐inorganic cesium lead bromide (CsPbBr3) solar cells tailored with carbon electrodes to simultaneously harvest solar and water‐vapor energy. Upon interfacial modification and plasma treatment, the bifunctional PSCs yield a maximum power conversion efficiency up to 9.43 % under one sun irradiation according to photoelectric conversion principle and a power output of 0.158 μW with voltage of 0.35 V and current of 0.45 μA in 80 % relative humidity through the flowing potentials at the carbon/water interface. The initial efficiency is only reduced by 2 % on exposing the inorganic PSC with 80 % humidity over 40 days. The successful realization of physical proof‐of‐concept multi‐energy integrated solar cells provides new opportunities of maximizing overall power output. [ABSTRACT FROM AUTHOR]

Dye-sensitized solar cell (DSSC) is a promising solution to relieve global energy crisis and environmental issues because of its superiority in low cost, easy fabrication procedures and relatively high efficiency. The decrease of fabrication cost without sacrifice of power conversion efficiency of the DSSCs can doubtlessly contribute to its commercial application. Here we report a new Pt-free RuCoSe ternary alloy counter electrode (CE) by electrodepositing. The DSSC device with RuCoSe ternary alloy CE achieves a power conversion efficiency of 9.07%, which is higher than 7.03% from Pt-only CE based DSSC. The easy preparation method and promising results provide a new method for decreasing cost but enhancing photovoltaic performance of DSSCs. [ABSTRACT FROM AUTHOR]

Abstract: All‐inorganic perovskite solar cells with high efficiency and improved stability are promising for commercialization. A multistep solution‐processing method was developed to fabricate high‐purity inorganic CsPbBr3 perovskite films for use in efficient solar cells. By tuning the number of deposition cycles (n) of a CsBr solution, the phase conversion from CsPb2Br5 (n ≤3), to CsPbBr3 (n=4), and Cs4PbBr6 (n≥5) was optimized to achieve vertical‐ and monolayer‐aligned grains. Upon interfacial modification with graphene quantum dots, the all‐inorganic perovskite solar cell (without a hole‐transporting layer) achieved a power conversion efficiency (PCE) as high as 9.72 % under standard solar illumination conditions. Under challenging conditions, such as 90 % relative humidity (RH) at 25 °C or 80 °C at zero humidity, the optimized device retained 87 % PCE over 130 days or 95 % over 40 days, compared to the initial efficiency. [ABSTRACT FROM AUTHOR]

Abstract: All‐inorganic perovskite solar cells with high efficiency and improved stability are promising for commercialization. A multistep solution‐processing method was developed to fabricate high‐purity inorganic CsPbBr3 perovskite films for use in efficient solar cells. By tuning the number of deposition cycles (n) of a CsBr solution, the phase conversion from CsPb2Br5 (n ≤3), to CsPbBr3 (n=4), and Cs4PbBr6 (n≥5) was optimized to achieve vertical‐ and monolayer‐aligned grains. Upon interfacial modification with graphene quantum dots, the all‐inorganic perovskite solar cell (without a hole‐transporting layer) achieved a power conversion efficiency (PCE) as high as 9.72 % under standard solar illumination conditions. Under challenging conditions, such as 90 % relative humidity (RH) at 25 °C or 80 °C at zero humidity, the optimized device retained 87 % PCE over 130 days or 95 % over 40 days, compared to the initial efficiency. [ABSTRACT FROM AUTHOR]

Pursuit of low-cost and large-scale method to prepare carbon quantum dots (CQDs) is a persistent objective in recent years. In this work, we have successfully synthesized a series of nitrogen-doped carbon quantum dots (N-CQDs) under different hydrothermal temperature employing Eichhornia crassipes (ECs) as precursors. Considering the pollution ability to water and low-cost, this study may direct the novel path to convert waste material to useful quantum dots. After measurements such as TEM, XRD, Raman, XPS, PL as well as the UV–vis absorbance ability, outstanding optical properties have been discovered. In this fashion, solar cells are tentative to be fabricated, yielding the maximized solar-to-electrical conversion efficiency of 0.17% with a good fill factor of 67%. Meanwhile, the above-mentioned quantum dots also show the up-conversion ability, suggesting the potential application in infrared detection or broadening light-absorbing devices. [ABSTRACT FROM AUTHOR]

The supercapacitor that can operate at high-temperature are promising for markedly increase in capacitance because of accelerated charge movement. However, the state-of-the-art polymer-based membranes will decompose at high temperature. Inspired by solid oxide fuel cells, we present here the experimental realization of high-temperature supercapacitors (HTSCs) tailored with porous ceramic separator fabricated by yttria-stabilized zirconia (YSZ) and nickel oxide (NiO). Using activated carbon electrode and supporting electrolyte from potassium hydroxide (KOH) aqueous solution, a category of symmetrical HTSCs are built in comparison with a conventional polymer membrane based device. The dependence of capacitance performance on temperature is carefully studied, yielding a maximized specific capacitance of 272 F g −1 at 90 °C for the optimized HTSC tailored by NiO/YSZ membrane. Moreover, the resultant HTSC has relatively high durability when suffer repeated measurement over 1000 cycles at 90 °C, while the polymer membrane based supercapacitor shows significant reduction in capacitance at 60 °C. The high capacitance along with durability demonstrates NiO/YSZ membrane tailored HTSCs are promising in future advanced energy storage devices. [ABSTRACT FROM AUTHOR]

Bifacial photovoltaics are promising devices for significantly harvesting solar energy and generating power from either front or rear side. We present here the fabrication of new category of high-performance bifacial dye-sensitized solar cells (DSSCs) tailored with transparent S-doped carbon quantum dots (S-CQDs)/metal selenide counter electrodes. Arising from photoexcitation of S-CQDs and therefore increased electron density at electrode surfaces, the catalytic ability of S-CQDs tailored counter electrodes is markedly enhanced under solar irradiation. The bifacial DSSCs yield maximized front and rear efficiencies of 9.15% and 6.26%, respectively. [ABSTRACT FROM AUTHOR]

A great challenge for state-of-the-art photovoltaic devices is to realize electric power generation in all weathers. We constructively demonstrate here the conversion from biomass to carbon quantum dots for all-weather carbon quantum dot solar cells that can generate electricity in the daytime and in the dark. The combination of green-emitting long persistence phosphors with mesoscopic titanium dioxide realizes optical storage by composite photoanode under illumination and excitation to monochromatic green light in the dark. The optimized all-weather solar cell yields maximized dark power conversion efficiency as high as 7.97% along with persistent electricity output for several hours. This work begins a photovoltaic revolution to forward all-weather solar cells as future energy solutions. [ABSTRACT FROM AUTHOR]

A promising but challenging problem for state-of-the-art solar cells is to persistently generate power in the daytime and dark. To address this profound issue, all-weather bifacial solar cells are built by combining long persistence phosphor (LPP) tailored fluorescent film with bifacial dye-sensitized solar cells. On behalf of the solar energy storage and fluorescent excitation behaviors of LPP phosphors, the so-called all-weather solar cells yield a maximized photoelectric conversion efficiency of 10.04% and a dark efficiency as high as 21%. Moreover, the newly launched all-weather solar cells with 32 modules can lighten a lamp, demonstrating a predictable application in future energy harvesting. The current work could also extend our knowledge to more advanced all-weather solar cells. [ABSTRACT FROM AUTHOR]

Photovoltaics are promising solutions to energy crisis and environmental pollution problems. The dye-sensitized solar cells with mesoscopic structures have attracted growing interests because of zero emissions, easy fabrication, scalable materials and techniques, etc . However, the state-of-the-art dye-sensitized solar cells have narrow spectral absorption for photoelectric conversion and high electron-hole recombination rate under sunlight illumination. Therefore, it is a persistent object to make wide-spectral absorption and fast charge extraction solar cells for energy harvest in both solar and dark-light conditions. To address this issue, we present here experimental realization of a category of solar cells converting visible and near-infrared light into electricity by co-sensitizing photoanode with N719 dye and polyethylene glycol (PEG) modified carbon quantum dots (PEG- m -CQDs), arising from up-conversion and hole-transporting behaviors of PEG- m -CQDs as well as photofluorescence of green-emitting long persistence phosphors. The optimized solar cell yields maximized photoelectric conversion efficiencies of 9.89% and 25.81% under simulated sunlight (air mass 1.5, 100 mW cm −2 ) illumination and dark conditions, respectively. This work is far from optimization, but the physical proof-of-concept hybridized solar cell may markedly increase electricity generation time and total power output of photovoltaic platforms. [ABSTRACT FROM AUTHOR]

We present here a symmetrically structured bifacial solar cell tailored by two fluorescent photoanodes and a platinum/titanium/platinum counter electrode, yielding extra-high short-circuit current densities as high as 28.59 mA cm−2 and 119.9 μA cm−2 in simulated sunlight irradiation (100 mW cm−2, AM1.5) and dark–light conditions, respectively. [ABSTRACT FROM AUTHOR]

We present here a carbon quantum dot (CQD) tailored counter electrode (CE) for a bifacial dye-sensitized solar cell (DSSC). Arising from wide spectral absorption, high optical transmission and the electron-enriched surface of the CE, the final bifacial DSSC device yields front and rear efficiencies of 9.08% and 7.01%, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • The PAMPS/NQDs with higher hole mobility and conductivity improves hole transport. • Modifying PAMPS/NQDs induced lower interfacial energy barrier boosts hole extraction. • The PAMPS/NQDs heals the defects of CsPbBr 3 film and enhances the hydrophobicity. • The unsealed device achieves a best PCE of 10.21% and excellent long-term stability. The regulation of the interface energetics and the simultaneous passivation of the surface defects of perovskite (PVK) film play an important role in improving the efficiency and stability of perovskite solar cells (PSCs). Here, a composite modification of poly(2-acrylamide-2-methylpropanesulfonic acid) (PAMPS)/NiFe 2 O 4 quantum dots (NQDs) that is formed by the light-triggered polymerization of AMPS monomer in homogeneous AMPS/NQDs is launched at the interface of PVK/carbon in all-inorganic CsPbBr 3 PSCs. Due to the higher hole mobility and conductivity of PAMPS/NQDs and its interface modification induced better energy level alignment and interfacial contact, the hole transport and extraction are significantly promoted. Combined with the simultaneous passivation of cations and anions (Cs+, Pb2+ and Br-) defects on CsPbBr 3 PVK surface by the S O, C O, N H and O H groups in PAMPS, the non-radiative recombination is effectively restrained, rendering a champion power conversion efficiency of 10.21 % with excellent high humidity and temperature (85 % RH, 85 °C) and light soaking tolerances for PAMPS/NQDs composite modified carbon-based CsPbBr 3 PSCs without encapsulation in air, which is markedly higher than the 6.81 % efficiency of the control device. [ABSTRACT FROM AUTHOR]

Exploration of cost-effective and transparent counter electrodes (CEs) with high electrocatalytic activity has been a persistent objective of bifacial dye-sensitized solar cells (DSSCs) development. Here, with an aim of accelerating charge transfer and increasing the active sites of a transparent CE, molybdenum sulfide (MoS 2 ) decorated aniline complexes are synthesized by a reflux technique and subsequently in-situ polymerized for transparent polyaniline (PANi)-MoS 2 complex CEs for efficient bifacial DSSCs. The preliminary results indicate that the electrocatalytic activity toward I 3 − reduction of PANi-MoS 2 complex CE is dramatically enhanced due to the fast charge transfer between PANi (N atoms) and MoS 2 (Mo atoms) by the metal (dπ)-nitrogen (pπ) antibonding interaction. Owing to the high optical transparency, electrocatalytic reduction toward I 3 − species, superior charge-transfer ability for I − /I 3 − redox couples, the bifacial DSSCs based on PANi-6 wt‰ MoS 2 complexes CE yield a maximum power conversion efficiency of 7.99% from front irradiation, 3.40% from rear irradiation and 9.71% from both irradiation, which are higher than front, rear and both efficiencies of 6.37%, 1.78% and 7.50% for DSSC employing PANi CE, respectively. The high optical transparency and electrocatalytic activity along with simple preparation, relatively low cost and scalability demonstrate the potential use of PANi-MoS 2 complex as a robust CE in bifacial DSSCs. [ABSTRACT FROM AUTHOR]

The high-temperature supercapacitors have attracted growing attentions because the improved charge diffusion kinetics and ion conductivity of the electrolytes at elevated temperatures cause high capacitances. However, the state-of-the-art aqueous and/or anhydrous electrolytes always suffer from water or organic solvent evaporation, poor thermal stability and toxicity. We presented here a wide-temperature window supercapacitor made with an activated carbon electrode, a ceramic membrane separator as well as an electrolyte containing 1-methylimidazolium trifluoromethanesulfonate ([MI m ][OTf]) ionic liquid and ethylene glycol (EG) organic solution of potassium hydroxide (KOH) ([MI m ][OTf]/KOH/EG). By studying the impacts of temperature on capacitance, a maximized specific capacitance of 289 F g −1 was achieved at 130 °C. Moreover, the champion supercapacitor presented an outstanding charging/discharging stability over 1500 cycles at 130 °C. The high capacitance along with long-term stability suggest that the ionic liquid electrolyte is prospective for wide-temperature window supercapacitors. [ABSTRACT FROM AUTHOR]

Pursuit of good inhibition performance has been a persistent objective for advanced inhibitor industry. Here we demonstrate the experimental realization of a new corrosion inhibitor acrylamide methyl ether (AAME) from N -Methylol acrylamide (N-MAM) for mild steel in 1 M HCl. The resultant adsorption films have inhibition efficiency as high as 96.2%. Moreover, a theoretical investigation is also launched to demonstrate the potential mechanism behind the promising corrosion behaviors. This work represents a significant step forward, as it demonstrates how to make scalable AAME inhibitors as well as to enhance inhibition performances for high-efficiency and cost-effective corrosion inhibition platforms. [ABSTRACT FROM AUTHOR]

Creation of advanced ultraviolet light absorbers having crosslinking ability has been persistent objective for anti-ultraviolent aging polymers. We present here the integration of 2, 4-dihydroxybenzophenone (UV-0) and N-methylol acrylamide (NMA) for novel ultraviolet absorber namely (3,5-dimethacrylamide-2,4-dihydroxyphenyl) (phenyl)methanone (UV-CA), which is subsequently utilized as a crosslinking agent after suffering Friedel–Crafts reaction. The preliminary results demonstrate that quantum chemical calculations (DFT) is a promising avenue in demonstrating the optimized geometry, charges, energy levels and UV electronic absorption bands of the UV-CA in the singlet (steady and excited states). The structure parameters and natural band orbital (NBO) calculations suggest that the intramolecular hydrogen bond (IMHB) in the UV-0 group is significantly enhanced in comparison to that between UV-0 and NMA groups. The acrylic acid polymers functionalized with UV-CA yield high crosslinking degree and robust UV absorbing performance. The impressive results demonstrate that quantum chemical calculations are promising in organic synthesis to develop advanced compounds. [ABSTRACT FROM AUTHOR]

The pursuit of efficient anticorrosion coatings containing polyaniline (PANI) has been a persistent objective. We present here the experimental realization of PANI microfibers by a simple electrospinning strategy. The resultant anticorrosion coating at an optimal PANI dosage of 25 wt% shows an impressive anticorrosion efficiency of 99.96% even after 20-days test in 0.1 M H 2 SO 4 . The elevated anticorrosion behavior may be attributed to the compact morphology of PANI/poly(methyl methacrylate) microfiber coating. The current study on PANI microfibers provides a new approach of enhancing anticorrosion behaviors of anticorrosion coatings. [ABSTRACT FROM AUTHOR]

Exploration of efficient platinum alloy counter electrodes (CEs) and understanding their electrocatalytic mechanism toward I 3 − reduction reaction have been two arising objectives for high-efficiency dye-sensitized solar cells (DSSCs). Here we demonstrate the experimental realization of bimetallic PtM (M = Pd, Ag) alloy nanotube (NT) CE electrocatalysts by an one-step templated synthesis for efficient DSSCs. The preliminary results demonstrate that the alloying of Pt with Pd or Ag for high surface-to-volume CE can significantly enhance the electrocatalytic activity in comparison with pristine Pt electrode. The promising electrocatalytic performances of the PtM CEs are mainly attributed to the good matching of their work functions to redox potential of I − /I 3 − couples and electron-enriched alloy surface. When fabricated into liquid-junction DSSCs, the impressive power conversion efficiencies up to 8.09% and 7.34% are determined for the cells with PtPd and PtAg NTs, yielding cell efficiencies enhancements of 18.4% and 5.9% in comparison with 6.93% for pristine Pt based DSSC, respectively. Moreover, the long-term stabilities are also increased due to competitive reactions between Pd/Ag and liquid electrolyte, protecting the Pt atoms from being dissolved by redox electrolyte. [ABSTRACT FROM AUTHOR]