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It is highly desired to improve the visible‐light activity of g‐C3N4 for H2 evolution by constructing closely contacted heterojunctions with conductive polymers. Herein, a polymer nanocomposite photocatalyst with high visible‐light activity is fabricated successfully by coupling nanosized polypyrrole (NPPy) particles onto g‐C3N4 nanosheets through a simple wet‐chemical process, and its visible‐light activity is improved further by constructing Mg−O bridges between the NPPy and g‐C3N4. The amount‐optimized bridged nanocomposite displays an approximately ninefold improvement in visible‐light activity compared with g‐C3N4. On the basis of transient‐state surface photovoltage responses, photoluminescence spectra, .OH amount evaluation, and photoelectrochemical curves, it is concluded that the exceptional photoactivity can be attributed to the significantly promoted charge transfer and separation along with visible photosensitization from NPPy. Interestingly, it is confirmed that the promoted charge separation depends mainly on the excited high‐level electron transfer from g‐C3N4 to NPPy by single‐wavelength photocurrent action spectra. This work provides a feasible strategy for designing polymer nano‐heterojunction photocatalysts with exceptional visible‐light activities.

Unraveling the sluggish charge separation, insufficient catalytic sites, and limited visible-light absorption for Z-scheme heterojunction photocatalysts still remains a great challenge toward CO2 conversion. Herein, ultrafine Au-modulated copper phthalocyanine/BiVO4 nanosheet heterojunctions (CuPc/Au-BVNS) with wide-visible-light responses have been successfully fabricated as efficient photocatalysts for CO2 conversion to CO, achieving 9-time and 35-time photoactivity improvement compared to pristine BVNS (ca. 5 nm) and the previously reported BiVO4 nanoflake (ca. 15 nm), respectively. The exceptional photoactivity is mainly attributed to the ultrafine Au interfacial modulation, which is well capable of inducing the directional electron migration of BVNS and the highly dispersed CuPc assembly with the increased loading amount, synergistically strengthening the Z-scheme charge transfer and separation mainly based on the surface photovoltage spectroscopy assisted with the monochromatic beam and electron paramagnetic resonance technique. Moreover, the in situ diffuse reflectance infrared Fourier transform spectroscopy, CO2 temperature-programmed desorption measurement, and electrochemical results demonstrate that the central metal Cu2+ in the high-dispersion CuPc exhibits potential catalytic functions for CO2 reduction, much superior to other metals in MPc (M = Co and Ni)-modified ones. This work highlights the importance of strengthening artificial Z-scheme charge transfer and provides new strategies for designing BiVO4-based heterojunctions by controllably assembling MPc toward efficient solar-driven CO2 conversion.

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Graphene-modulated ZnPc/BiVO4 Z-scheme heterojunctions for efficient visible-light catalytic CO2 conversion are achieved by increasing the optimized amount of highly dispersed ZnPc.

From the practical application of supercapacitors, the development of carbon materials with high volumetric performance is highly desired. We report the synthesis of B/N/O co-doped carbon by a facile one-step carbonization method of polyvinylpyrrolidone/melamine formaldehyde resin with boric acid/urea treatment and a subsequent washing process. It is shown that a boric acid/urea treatment is an effective approach to incorporating B into N/O enriched carbon and effectively restraining the generation of inert B-O and B-N species. Moreover, a boric acid/urea treatment and washing process can increase specific surface area, optimize pore structure, and retain many active heteroatoms without lowering density, contributing to good conductivity, fast charge transfer and electrolyte ion diffusion, and high volumetric performance. The fabricated B/N/O co-doped carbon shows high active heteroatoms of 8.69 at.% (N-5, N-6, B-C and O-I), moderate surface area, and pore volume (778.02 m 2 g −1 and 0.341 cm 3 g −1 ), high density (1.3 g cm −3 ), high specific volumetric, and gravimetric capacitances (309 F cm −3 and 238 F g −1 at 0.5 A g −1 ) and superior cycling stability. The assembled symmetric supercapacitor delivers relatively high volumetric energy density (11.5 Wh L −1 at 622 W L −1 ) in 6 M KOH electrolyte. The B/N/O co-doped carbon has great potential for applications in supercapacitors.

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Solar-driven carbon dioxide (CO2) reduction into valuable chemicals or feedstock is of great significance for the sustainable development of the environment and energy. Herein, we presented a photo-induced reduction method...