Facile construction of self-assembled Cu@polyaniline nanocomposite as an efficient noble-metal free cocatalyst for boosting photocatalytic hydrogen production

Photocatalytic Hydrogen production via water splitting is considered a sustainable ecofriendly pathway to replenish the current and future energy demands. In this study, the self-assembly synthesis of Cu nanospheres (～8 nm) surrounded by a thin conductive layer of polyaniline (Cu@PANI) was rationally engineered via in?situ polymerization. Afterward, it was successfully deposited onto the TiO₂ surface to improve the photocatalytic activities for hydrogen production. The optimal Cu@PANI/TiO₂ ternary photocatalyst produced a substantial hydrogen generation rate (HGR) of 17.7 mmol h^?1 g^?1, 207-fold higher than that of bare TiO₂. The performance was considerably improved compared with (Cu–TiO₂)/PANI and (PANI-TiO₂)/Cu composites prepared by changing the deposition sequence of Cu and PANI. Such an improved activity was because of multiple transferring paths of photogenerated electrons in the composite. Interestingly, the as-prepared ternary photocatalyst exhibited superior hydrogen evolution compared with the binary hybrids (Cu/TiO₂ and PANI/TiO₂). The exceptional performance of Cu@PANI/TiO₂ could be understood considering the distinctive electrical conductivity of PANI and heterojunction formed between PANI and TiO₂, as well as the merits of the Schottky junction constructed between Cu and PANI. These superior features could efficiently suppress the recombination rate of the photogenerated electron–hole pairs and maximize the photocatalytic activity. This study provides new insights for understanding the effect of electron transfer pathways on photocatalytic activities.     

Enhanced catalytic behavior of h-BN supported CuNi bimetallic catalysts in hydrolytic dehydrogenation of NH3BH3

The hydrolysis of ammonia borane (NH₃BH₃, AB) is an efficient strategy for high-purify hydrogen evolution. However, it is indispensable to develop a suitable catalyst because this reaction is kinetically infeasible at room temperature. In this work, we prepared a series of nano hexagonal boron nitride (h-BN) supported CuNi bimetallic catalysts through a facile adsorption-chemical reduction procedure. The effects of various molar ratios of Cu to Ni and CuNi loadings on AB hydrolysis were investigated in details. Benefitting from the proper porous structure, the interesting alloy effect of Cu and Ni, as well as the synergistic effect between h-BN and CuNi, 20 wt% Cu_0.5Ni_0.5/h-BN displays the highest catalytic activity among the as-prepared catalysts. Apart from satisfactory durability, the corresponding hydrogen generation rate, turnover frequency at 303 K in base solution and apparent activation energy are 2437.0 mL g^?1 min^?1, 6.33 min^?1 and 23.02 kJ mol^?1, respectively, which are very outstanding compared with many previous results. Our work not only provides a proper non-precious metal catalyst for hydrogen generation from the hydrolysis of chemical hydrogen storage materials but also offers a facile strategy for synthesizing metallic functional materials.     

Polyaniline encapsulated Ti-MOF/CoS for efficient photocatalytic hydrogen evolution

We report the study of conductive polyaniline (PANI) chain embedded Ti-MOF functionalized with CoS as a cocatalyst for hydrogen evolution reaction (HER) application. The post synthetically modified hybrid photocatalyst PANI/Ti-MOF/CoS greatly influences the redox and e^? ? h⁺ separation process and exhibits an impressive rate of HER (～1322 μmol h^?1g^?1), suppressing the pristine Ti-MOF (～62 μmol h^?1g^?1) with apparent quantum yield (AQY) of ～3.2 and transient current response of ～46.4 μA cm^?2. In this system, Ti-MOF provides the circulation of Ti³⁺ and Ti⁴⁺ to the reaction of photocatalytic H₂ generation, where the additional PANI and CoS amended the performance of H₂ production through electron enrichment and thereby improving the stability and integrity of Ti-MOF. The Electrochemical studies demonstrated increased photocurrent by interweaving Ti-MOF crystal with PANI through cation-π interaction thereby enhancing interface connection and then promoting electron transfers. The charge dynamics revealed the initial charge transfer from photoexcited PANI to encapsulated MOF framework to boost the photocatalytic performance of the system. Further, the electron movement at the Ti-MOF/CoS interface is investigated through work function and electrochemical potential of electrons (Fermi level). DFT results demonstrate the importance of CoS in improving the photocatalytic performance of hybrid Ti-MOF catalyst, which leads to superior catalytic behaviour. These results establish that the encapsulation of catalytic active sites inside MOFs with desirable energy band gaps would be an ideal choice for the production of solar fuels.     

Rational design of interfacial energy level matching for CuGaS2 based photocatalysts over hydrogen evolution reaction

CuGaS₂(CGS) is effectively synthesized by a one-step solid-phase sintering method. The conduction band maximum, valence band maximum and flat band potential of the obtained CGS are ?1.14, 1.21 and 0.33 V vs RHE, respectively. When the Cu to Ga atom ratio is 1: 1.4 in the raw material, the prepared CuGaS₂ exhibits the highest visible-light (λ?420 nm) H₂ production activity. The hydrogen production rate of CuGaS₂ reaches 1.12 mmol g^?1 h^?1 under visible-light radiation. When Ruthenium is loaded as cocatalyst, the H₂ production rate of CuGaS₂@Ru is promoted to 3.38 mmol g^?1 h^?1. At the same, the interior component of photo-induced carries transfer among photoharvestor and cocatalyst has been revealed. This research provides a facile strategy to fabricate CuGaS₂ with excellent photocatalytic performance for H₂ production.     

Photoelectrochemical properties of doped polyaniline: Application to hydrogen photoproduction

The semi conducting properties of doped polyaniline (emeraldine-salt, PANI) elaborated by chemical route are investigated by the photo-electrochemical technique. The band gap is found to be 1.48 eV and the transition is directly allowed. The electrical conduction obeys to an exponential law with activation energy of 0.13 eV. p-type conductivity is evidenced from the cathodic photocurrent. The energy band diagram clearly shows the spontaneous hydrogen photo evolution. The potential of the conduction band of PANI (−0.93 V_SCE) determined from the capacitance measurements is suitably positioned with respect to H₂O/H₂ level (−0.66 V_SCE). Therefore, the photocatalytic properties of this material has been evaluated according to the hydrogen generation. The best performance is achieved at pH ∼7 with a liberation rate of 0.113 mL h⁻¹ (mg catalyst)⁻¹ and a quantum efficiency of 0.18% under visible light (29 mW cm⁻²). An increase of 56% is obtained on the hetero-system PANI/TiO₂.     

Fe2P nanoparticles as highly efficient freestanding co-catalyst for photocatalytic hydrogen evolution

Design of non-noble-metal artificial photosynthesis system that can split water with high apparent quantum yield (AQY) and robust stability remains a fundamental challenge. Here we report that a physical mixture of Fe₂P nanopaticles (NPs) and CdS nanosheets (NSs) can gives AQY of photocatalytic hydrogen production as high as 90% at 420 nm monochromatic light with ethanol as electron donor at strong alkaline conditions. The highest rate for hydrogen production reached about 220 mmol g^?1 h^?1. In this hybrid photocatalyst system, free standing Fe₂P NPs act as efficient and robust noble-metal-free co-catalysts and ultrathin CdS NSs are used as the photosensitizer. PL and TRPL results demonstrate that photoexcited electron can transfer from the conduction band of the excited CdS to Fe₂P, which aided charge separation and enhanced the hydrogen evolution activity. Femtosecond transient absorption result reveals that the time-averaged interfacial electron transfer (ET) rate constant (<k_ET>) from CdS NSs to Fe₂P is about 7.4 × 10⁹ s^?1 under the guarantee of the scavenging of photoexcited hole immediately, which is one order faster than the electron relaxation rate in pure CdS NSs.     

Photocatalytic hydrogen production over CuO and TiO2 nanoparticles mixture

Cheap and efficient photocatalysts were fabricated by simply mixing TiO₂ nanoparticles (NPs) and CuO NPs. The two NPs combined with each other to form TiO₂/CuO mixture in an aqueous solution due to the opposite surface charge. The TiO₂/CuO mixture exhibited photocatalytic hydrogen production rate of up to 8.23 mmol h⁻¹ g⁻¹ under Xe lamp irradiation when the weight ratio of P25 to CuO was optimized to 10. Although the conduction band edge position of CuO NPs is more positive than normal hydrogen electrode, the TiO₂/CuO mixture exhibited good photocatalytic hydrogen production performance because of the inter-particle charge transfer between the two NPs. The detailed mechanism of the photocatalytic hydrogen production is discussed. This mixing method does not require a complicated chemical process and allows mass production of the photocatalysts.     

Direct Z-scheme CoS/g-C3N4 heterojunction with NiS co-catalyst for efficient photocatalytic hydrogen generation

Facilitating the separation of photoexcited electron-hole pairs and enhancing the migration of photogenerated carriers are essential in photocatalytic reaction. CoS/g-C₃N₄/NiS ternary photocatalyst was prepared by hydrothermal and physical stirring methods. The optimized ternary composite achieved a hydrogen yield of 1.93 mmol g^?1 h^?1, 12.8 times that of bare g-C₃N₄, with an AQE of 16.4% at 420 nm. The enhanced photocatalytic activity of CoS/g-C₃N₄/NiS was mainly ascribed to the synergistic interaction between the Z-scheme heterojunction constructed by CoS and g-C₃N₄ and the NiS co-catalyst featuring a large amount of hydrogen precipitation sites, which realized the efficient separation and migration of photogenerated carriers. In addition, the CoS/g-C₃N₄/NiS heterojunction-co-catalyst system exhibited excellent photocatalytic stability and recyclability.     

Efficient photocatalytic H2 evolution over Cu and Cu3P co-modified TiO2 nanosheet

Schottky junction and p-n heterojunction are widely employed to enhance the charge transfer during the photocatalysis process. Herein, Cu and Cu₃P co-modified TiO₂ nanosheet hybrid (Cu–Cu₃P/TiO₂) was fabricated using an in situ hydrothermal method. The ternary composite achieved the superior H₂ evolution rate of 6915.7 μmol g^?1 h^?1 under simulated sunlight, which was higher than that of Cu/TiO₂ (4643.4 μmol g^?1 h^?1) and Cu₃P/TiO₂ (6315.8 μmol g^?1 h^?1) and pure TiO₂ (415.7 μmol g^?1 h^?1). The enhanced activity can be attributed to the collaboration effect of Schottky junction and p-n heterojunction among Cu/TiO₂ and Cu₃P/TiO₂, which can harvest the visible light, reduce the recombination of charge carriers and lower the overpotential of H₂ evolution, leading to a fast H₂ evolution kinetics. This work develops a feasible method for the exploration of H₂ evolution photocatalyst with outstanding charge separation properties.     

Effect of Pt loading on the hydrogen production of CNT/Pt composites functionalized with carboxylic groups

This work reports the morphological and photocatalytic hydrogen generation properties of CNT/Pt composites with and without functionalization by carboxylic/oxygen groups. The composites with and without functionalization were named f-CNT/Pt and CNT/Pt, respectively. Several f-CNT/Pt and CNT/Pt composites with different content of Pt NPs (from 0 to 30 wt%) were synthesized and analyzed by scanning electron microscopy (SEM). Those images revealed that the composites without functionalization presented higher agglomerations of Pt nanoparticles (NPs). Furthermore, the average sizes of the Pt NPs in the named f-CNT/Pt composites (2.3–2.9 nm) were lower than these in the CNT/Pt composites (2.5–3.1 nm). The hydrogen generation rates were also calculated from the decomposition of pure water under UV irradiation (365 nm) and found maximum values of 45.4 and 193.9 μmol·h⁻¹ g⁻¹ for the CNT/Pt and f-CNT/Pt composites (they contained 20 wt% of Pt NPs), respectively. Additional experiments for hydrogen generation were achieved using sodium sulfite as sacrificial agent; in this case, a maximum value of 13850 μmol·h⁻¹ g⁻¹ was obtained for the f-CNT/Pt composite. The f-CNT/Pt composites produced more hydrogen than the CNT/Pt composites because they presented higher content of defects; this was confirmed by the Raman spectra. We also showed that the Pt NPs acted as electron trap centers, which delayed the recombination of the photogenerated electrons and holes, this in turn, enhanced the hydrogen generation rates of the composites (the hydrogen generation was maximized by varying the content of Pt NPs deposited on the CNTs). The CNT/Pt composites presented here were simpler and easier to synthesize than the previous published ternary systems based on TiO₂, CNTs and Pt NPs.     

Synthesis of MOF/MoS2 composite photocatalysts with enhanced photocatalytic performance for hydrogen evolution from water splitting

With the shortage of global fossil energy and the increasing crisis of environmental deterioration, hydrogen energy has become an environmentally benign alternative as a clean energy source. In most studies on photocatalytic hydrogen production, novel photocatalytic material has played an important role to enhance the hydrogen production rate. In this study, the optimal conditions for the synthesis of MoS₂ were established through series of characterizations with 190 °C calcination temperature and 1 wt% PEG surfactant addition. The best conditions for synthesizing MOF include copper nitrate as the copper precursor, 30% ultrasonic amplitude, and 240 °C calcination temperature. After adding 1 wt% MOF in MOS₂, a flower-like structure with small particle size, uniform distribution, regularity, and large surface pores, has been formed, where its unit is modified with many rough, porous, and high specific surface area octahedral structures. In addition, 1MOF/MOS₂ has the most negative conduction band edge (?0.135 V), the smallest charge transfer resistance (R_ct = 1.78 Ω), the largest photo current (11.1 mA/cm²), the lowest PL spectral peak intensity, and excellent photocatalytic stability. The above morphological features and optical properties can significantly form more active sites, enhance the electron transfer rate, and inhibit the electron-hole recombination, thus making the MOF/MOS₂ composite photocatalyst achieve the maximum hydrogen production capacity (626.3 μmol g^?1 h^?1).     

TiO2 nanotubes coupled with nano-Cu(OH)2 for highly efficient photocatalytic hydrogen production

Noble-metal-free Cu(OH)₂/TNTs (TNTs: TiO₂ nanotubes) nanocomposite photocatalysts were successfully prepared by loading nano-Cu(OH)₂ on TNTs via a hydrothermal-precipitation process. These were then characterized in terms of morphology and physicochemical properties by employing TEM, XRD, XPS, BET, UV–Vis DRS and PL. The effects of Cu(OH)₂ loading, amount of catalyst on the photocatalytic hydrogen production performance of Cu(OH)₂/TNTs were investigated in detail in aqueous methanol solution under UV irradiation. The results show that, compared with pure TNTs, the TNTs loaded with highly dispersed 8 wt% Cu(OH)₂ exhibited remarkably improved activity for hydrogen production (the largest quantity of evolved hydrogen was ca. 14.94 mmol h⁻¹ g⁻¹ catalyst) with good photostability. This high activity is attributed to the strong synergistic function of Cu(OH)₂/TNTs, including suitable potential of Cu(OH)₂/Cu (E⁰ = −0.222 V) between conduction band (−0.260 V) of TNTs and the reduction potential of H⁺/H₂ (E⁰ = 0.000 V), a unique tubular microstructure of TNTs coated with nano-Cu(OH)₂, large BET specific surface area and high dispersion of Cu(OH)₂. Furthermore, a process mechanism for methanol/water decomposition over Cu(OH)₂/TNTs is proposed to understand its high activity.     

A novel in-situ strategy develops for Mo2C nanoparticles incorporated on N,P co-doped stereotaxically carbon as efficient electrocatalyst for overall water splitting

Developing cost-effective and remarkable electrocatalysts toward oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) performs excelling role in boosting the hydrogen energy application. Herein, a novel in-situ one-pot strategy is developed for the first time to synthesize molybdenum carbide nanoparticles (Mo₂C NPs) incorporated on nitrogen (N) and phosphorous (P) co-doped stereotaxically carbon (SC). The optimized Mo₂C NPs/N, P–SC–800 electrocatalyst exhibits lower overpotentials of 131 and 287 mV for HER and OER to deliver a current density of 10 mA cm^?2 in 1.0 M KOH medium with smaller Tafel slopes of 58.9 and 74.4 mV/dec, respectively. In addition, an electrolyzer using Mo₂C NPs/N, P–SC–800 electrode as cathode and anode delivers a current density of 10 mA cm^?2 at a small voltage of 1.64 V for overall water splitting. The excellent water splitting performance could be ascribed to optimum Mo₂C NPs for more accessible active sites, highly active N, P-SC networks for accelerated electron transfers, and synergetic effect between Mo₂C NPs and N, P-SC networks. The N, P-SC network not only enhances the overall dispersion of Mo₂C NPs but also contributes numerous electroactive edges to enhance the performance of HER, OER, and overall water splitting activity. This research work explores the in-situ one-step strategies of advanced, cost-effective, and non-precious metal electrocatalysts for efficient water splitting and motivates the consideration of a novel class of heteroatom doped stereotaxically carbon nanocomposites for sustainable energy production.     

A novel Z-type multidimensional FeSe2/CuSe heterojunction photocatalyst with high photocatalytic and photoelectrochemical performance

A novel Z-type multidimensional FeSe₂/CuSe heterojunction photocatalyst was synthesized by a hydrothermal progress. In the reaction, 1D FeSe₂ nanorods will load on the surface of 2D CuSe nanosheets to construct heterojunction. This Z-type heterojunction can improve the carriers separated efficiency and reduce internal resistance (as low as 0.31 kΩ). More importantly, the catalysts display both high oxidation and reduction ability confirmed by photocatalytic and photoelectrochemical test. Under the optimum concentration, the catalyst showed 7.4 times of degradation tetracycline hydrochloride rate, and 4 times of photocurrent density than pure CuSe. Active specie O₂^?? was detected by the electron spin resonance tool during photocatalytic degradation progress which could confirm that a Z-type heterojunction was constructed between CuSe and FeSe₂. In this Z-type heterojunction, photoinduced electrons in the conduction band of FeSe₂ can directly inject the valence band of CuSe while photoinduced electrons in the conduction band position of CuSe and photoinduced holes in the valence band position of FeSe₂ will remain. The remained photoinduced electrons in the conduction band of CuSe can generate O₂^?? to oxide tetracycline hydrochloride as well as photoinduced electrons to produce hydrogen. This work highlights a simple strategy of Z-tpye selenides heterostructure for oxidation and reduction application.     

Graphite carbon nitride loaded nitrogen-doped carbon and cobalt nanoparticles ternary photocatalyst for enhanced solar-driven hydrogen evolution

In this paper, we designed a composite photocatalytic system in which cobalt nanoparticles (Co NPs) are attached to nitrogen-doped carbon (N-d-C) and co-bonded to the surface of the noted photocatalyst graphite carbon nitride (g-C₃N₄), showing an excellent photocatalytic hydrogen production. The bulk g-C₃N₄ was formed in the first thermal treatment in air using melamine as a precursor. Subsequently, the secondary calcination under N₂ led to the synchronous fabrication of N-d-C/Co NPs and their combination with g-C₃N₄ to form a novel ternary photocatalyst (g-C₃N₄/N-d-C/Co NPs). Co NPs exposed on the surface of the nanomaterials endowed much more reaction sites than g-C₃N₄ for photocatalytic hydrogen production. Meanwhile, the embedded N-d-C provided an additional transfer approach for photocarriers. The as-prepared composite nanomaterials own a relatively high specific surface area of 97.45 m² g^?1 with an average pore size of 3.83 nm. As a result, compared with pristine g-C₃N₄ (～25.35 μmol g^?1 h^?1), the photocatalytic performance was increased by over 10 times (～270.05 μmol g^?1 h^?1). Our work gives a novel approach for highly active g–C₃N₄–based photocatalysts in the field of photocatalysis.     

LED light-induced enhanced photocatalytic hydrogen evolution on Au@TiO2 core–shell modified by nitrogen doping and reduced graphene oxide

This study focused on the large band gap of TiO₂ for its use as a photocatalyst under light emitting diode (LED) light irradiation. The photocatalytic activities of core–shell structured Au@TiO₂ nanoparticles (NPs), nitrogen doped Au@TiO₂ NPs, and Au@TiO₂/rGO nanocomposites (NCs) were investigated under various light intensities and sacrificial reagents. All the materials showed better photocatalytic activity under white LED light irradiation than under blue LED light. The N-doped core–shell structured Au@TiO₂ NPs (Au@N–TiO₂) and Au@TiO₂/rGO NCs showed enhanced photocatalytic activity with an average H₂ evolution rate of 9205 μmol h^?1g^?1 and 9815 μmol h^?1g^?1, respectively. All these materials showed an increasing rate of hydrogen evolution with increasing light intensity and catalyst loading. In addition, methanol was more suitable as a sacrificial reagent than lactic acid. The rate of hydrogen evolution increased with increasing methanol concentration up to 25% in DI water and decreased at higher concentrations. Overall, Au@TiO₂ core–shell-based nanocomposites can be used as an improved photocatalyst in photocatalytic hydrogen production.     

Construction of 1D/0D/2D Zn0.5Cd0.5S/PdAg/g-C3N4 ternary heterojunction composites for efficient photocatalytic hydrogen evolution

A high-efficiency and easy-available approach was developed to obtain a ternary heterojunction composites with advanced hydrogen evolution reaction (HER) performance under visible light by water split. PdAg bimetallic nanoparticles make a close contact interface between g-C₃N₄(CN) and Zn_0.5Cd_0.5S(ZCS). Under visible light irradiation, CN and ZCS are both excited to generate electron-hole pairs, PdAg bimetallic nanoparticles act as a bridge between CN and ZCS. Not only can the photogenerated electrons from CN be captured, but they can also be quickly transferred to the surface of ZCS and participate in the photocatalytic reaction to release H₂, and the recombination of charge carriers between the contact interface of ZCS and CN can be significantly inhibited. In addition, the thin CN layer reduces the photocorrosion of the ZCS and enhances the specific surface area of the composite material. After testing, the composite material with 30 wt% ZCS and 4 wt% PdAg demonstrates hydrogen evolution performance, up to 6250.7 μmol g^?1h^?1, which is 753 times the hydrogen evolution rate of single-component CN and 12.6 times of ZCS/CN. Compared with single-component and two-component photocatalysts, the ternary ZCS/PdAg/CN photocatalyst achieves significantly enhanced photocatalytic activity.     

Photocorrosion-less stable heterojunction photoanode for efficient visible-light driven solar hydrogen generation

In this work, a heterostructure CdS/TiO₂ nanotubes (TNT) photoelectrode is decorated with Ni nanoparticles (NPs) to enhance hydrogen generation via the photoelectrochemical method. Herein, we report a systematic study of the effect of Ni NPs heterostructure photoelectrode to improve light absorption and photoelectrochemical (PEC) performance. The fabricated photoelectrodes were evaluated for photoelectrochemical hydrogen generation under simulated sunlight. The optimized Ni/CdS/TNT photoelectrode exhibited an improved photocurrent density of 6.5 mA cm^?2 in poly-sulfide aqueous media at a low potential of 0 V. Owing to the enhanced photocurrent density, Ni NPs also played a significant role in improving the stability of the photoelectrode. The synergistic effect with semiconductor ternary junction incites the surface plasmon resonance (SPR) for light-harvesting to enhance photoelectrochemical hydrogen generation.     

Efficient photothermal catalytic hydrogen production via plasma-induced photothermal effect of Cu/TiO2 nanoparticles

Developing appropriate photocatalyst with high efficiency is still the basic strategy for practical application of emerging technology. Herein, non-noble metal copper (Cu) nanoparticles were in situ hybrided with TiO₂ by a chemical reduction method. The crystal phase and structure were characterized by XRD, SEM, and TEM measurements. Hydrogen production results showed that Cu nanoparticles significantly improved the photocatalytic hydrogen production rate. The hydrogen production rate was as high as 24160.69 μmol g^?1 h^?1 at 100 °C, which was 36.25 and 8.46 times higher than the hydrogen production rates of pure TiO₂ and 0.13 wt% Cu/TiO₂ at room temperature, respectively. PL spectra, UV–vis spectra, IR images and photoelectrochemical measurements showed that the plasma-induced photothermal effect of Cu/TiO₂ nanoparticles, which raised the temperature of the reaction system and promoted photothermal catalytic performance. Briefly, this work provides a facile fabrication method of noble-metal-free photocatalysts featuring in low-cost and high efficiency. In the future, coupling the photothermal effect of plasmonic Cu to further speed up the kinetics should be another promising research direction for further improving hydrogen production.     

Hollow bimetallic M-Fe-P (M=Mn,Co, Cu) nanoparticles as efficient electrocatalysts for hydrogen evolution reaction

Searching for low-cost electrocatalysts with high activity towards the hydrogen evolution reaction (HER) is of great significance to enable large-scale hydrogen production via water electrolysis. In this study, by using inverse spinel MFe₂O₄(M = Mn, Fe, Co, Cu) nanoparticles (NPs) as the precursors, monodisperse bimetallic phosphide M-Fe-P NPs/C with hollow structures were readily obtained by a gas-solid annealing method. These hollow phosphide NPs displayed excellent HER activity in an acidic medium with a low loading amount of 0.2 mg cm⁻². In particular, the Co–Fe–P NPs/C shows highest HER activity that only requiring an overpotential of 97 mV to retain a current density of 10 mA cm⁻². A volcano relation between activity and incorporated elements was revealed. Incorporation of cation with high electronegativity stabilized the FeP active centres, while phase segregation resulted in the loss of activity for Cu–Fe–P NPs/C.